SYSTEMS AND METHODS FOR ADAPTING THE CONFIGURATION OF SIGNALS FOR A TIMING AND/OR FREQUENCY SYNCHRONIZATION

RELATED PROCEDURE(S)

Related Applications

[0001] This application claims the benefit of provisional patent application serial number 62/587,245, filed November 16, 2017, the disclosure of which is hereby incorporated herein by reference in its entirety.

Technical Field

[0002] The present disclosure relates to a cellular communications system and more specifically to adapting the configuration of signals such as, e.g., reference signals.

Background

New Radio (NR) Architecture

[0003] NR, which is also known as Fifth Generation (5G) or Next Generation (NG), architecture is being discussed in Third Generation Partnership Project (3GPP) and the current concept is illustrated in Figure 1 , where an enhanced or evolved Node B (eNB) denotes a Long Term Evolution (LTE) eNB, NR Node B (gNB) and NG eNB (ng-eNB) (or evolved eNB) denote NR Base Stations (BSs) where one NR BS may correspond to one or more Transmission/Reception Points (TRPs), and the lines between the nodes illustrate the corresponding interfaces which are under discussion in 3GPP. Further, Figure 2 illustrates deployment scenarios with NR BSs which are discussed in 3GPP.

Multi-Antenna Schemes in NR

[0004] Multi-antenna schemes for NR are currently being discussed in 3GPP. For NR, frequency ranges up to 100 gigahertz (GHz) are considered. High- frequency radio communication above 6 GHz suffers from significant path loss and penetration loss. Therefore massive Multiple Input Multiple Output (MIMO) schemes for NR are considered.

[0005] With massive MIMO, three approaches to beamforming have been discussed: analog, digital, and hybrid (i.e. , a combination of analog and digital beamforming). An example diagram for hybrid beamforming is shown in Figure 3. Beamforming can be on transmission beams and/or reception beams, network side or User Equipment (UE) side.

Beam Sweeping

[0006] The analog beam of a subarray can be steered toward a single direction on each Orthogonal Frequency Division Multiplexing (OFDM) symbol, and hence the number of subarrays determines the number of beam directions and the corresponding coverage on each OFDM symbol. Flowever, the number of beams to cover the whole serving area is typically larger than the number of subarrays, especially when the individual beam-width is narrow. Therefore, to cover the whole serving area, multiple transmissions with narrow beams differently steered in time domain are also likely to be needed. The provision of multiple narrow coverage beams for this purpose has been called“beam sweeping.” For analog and hybrid beamforming, the beam sweeping seems to be essential to provide the basic coverage in NR. For this purpose, multiple OFDM symbols, in which differently steered beams can be transmitted through subarrays, can be assigned and periodically transmitted.

[0007] Figure 4A illustrates an example of transmit beam sweeping on two subarrays. Figure 4B illustrates an example of transmit beam sweeping on three subarrays.

Synchronization Signal (SS) Block Configuration

[0008] A non-limiting example of SS block and SS burst configuration is described herein and can be assumed for the description provided herein. The signals comprised in an SS block may be used for measurements on a NR carrier, including intra-frequency, inter-frequency and inter- Radio Access

Technology (RAT) (i.e. , NR measurements from another RAT).

[0009] SS block (can also be referred to as SS / Physical Broadcast Channel (PBCH) block or SS Block (SSB)): NR Primary SS (PSS), NR

Secondary SS (SSS), and/or NR-PBCH can be transmitted within an SS block. For a given frequency band, an SS block corresponds to N OFDM symbols based on one subcarrier spacing (e.g., default or configured), and N is a constant. The UE shall be able to identify at least OFDM symbol index, slot index in a radio frame, and radio frame number from an SS block. A single set of possible SS block time locations (e.g., with respect to radio frame or with respect to SS burst set) is specified per frequency band. At least for multi-beams case, at least the time index of the SS block is indicated to the UE. The position(s) of actual transmitted SS blocks can be informed for helping CONNECTED/IDLE mode measurement, for helping CONNECTED mode UE to receive downlink data/control in unused SS-blocks, and potentially for helping an IDLE mode UE to receive downlink data/control in unused SS blocks. The maximum number of SS blocks within an SS burst , L, for different frequency ranges are:

• For frequency range up to 3 GHz, L is 4

• For frequency range from 3 GHz to 6 GHz, L is 8

• For frequency range from 6 GHz to 52.6 GHz, L is 64

[0010] SS burst set: One or multiple SS burst(s) further compose an SS burst set (or series) where the number of SS bursts within an SS burst set is finite.

From the physical layer specification perspective, at least one periodicity of the SS burst is supported. From the UE perspective, SS burst set transmission is periodic. At least for initial cell selection, the UE may assume a default periodicity of the SS burst transmission for a given carrier frequency (e.g., one of 5 milliseconds (ms), 10 ms, 20 ms, 40 ms, 80 ms, or 160 ms). The UE may assume that a given SS block is repeated with an SS burst (i.e., L=4, 8, or 64). Each SS block is in fact a beam. So, each SS block is repeated in every SS burst, i.e., after every SS burst period. By default, the UE may neither assume the NR Node B (gNB) transmits the same number of physical beam(s), nor the same physical beam(s) across different SS blocks within an SS burst set. In a special case, an SS burst set may comprise one SS burst.

[0011] For each carrier, the SS blocks may be time-aligned or overlap fully or at least in part, or the beginning of the SS blocks may be time-aligned (e.g., when the actual number of transmitted SS blocks is different in different cells).

[0012] Figure 5 illustrates an example configuration of SS blocks, SS bursts, and SS burst sets/series.

[0013] All SS blocks within a burst which can be up to 5 ms window, but the number of SS blocks within such window depends on the numerology (e.g., up to 64 SS blocks with 240 kilohertz (kFIz) subcarrier spacing). The actual length of the SS burst in time depends on the number of SS blocks (i.e. , beams) configured in the cell. An example mapping is illustrated in Figures 6A and 6B.

Tracking Reference Signal (TRS)

[0014] TRS is a reference signal for time and frequency tracking, which can be configured in a U E-specific way. TRS Resource Block (RB) position is configured by the gNB. TRS can be configured on a carrier or on an active Bandwidth Part (BWP) when an SS block is not present.

[0015] According to Technical Specification (TS) 38.211 V1.1.1 , the TRS is defined by the following reference signal sequence r(m) as:

where c(i) is a pseudo-random sequence. A TRS burst consists of four OFDM symbols transmitted in two consecutive slots.

[0016] The UE may assume that a TRS burst is quasi co-located with respect to delay spread, average delay, Doppler shift, and Doppler spread with the Physical Downlink Shared Channel (PDSCFI) Demodulation Reference Signal (DMRS). A Channel State Information Reference Signal (CSI-RS) may also be used as TRS, e.g., if TRSs are not present.

[0017] There are six parameters to be defined in RAN1 #89 meeting for TRS framework:

X: the length of the TRS burst in terms of number of slots Y: the TRS burst periodicity in terms of number of slots

S _f : TRS subcarrier spacing

S _t : TRS symbol spacing within a slot

N: Number of OFDM symbols per TRS within a slot

B: TRS bandwidth in terms of number of RBs

[0018] The considered values for the six parameters for further down- selection are:

X (the length of the TRS burst in terms of number of 14-symbol slots)

^■ 2 (for N=2+2, TRS symbols have the same symbol positions in the two consecutive slots)

• One of the following symbol positions per slot can be

configured by Radio Resource Control (RRC),

o Option 1 : symbols 4 and 8 (symbol index starts from

0)

o Option 2: symbols 5 and 9

o Option 3: symbols 6 and 10

o Note 1 : Potential down selection can be done until the next meeting. It is not limited to select only one option.

o Note 2: RRC signaling to configure TRS as above can be related to the existing RRC signaling for DMRS, CSI-RS, etc.

o Note 3: It is not precluded to have additional options.

^■ For Further Study (FFS): 1 and 4

Y (the TRS burst periodicity in ms)

^■ Consider further at least these values: 5, 10, 20, 40, 80 ms

^■ Consider less than 5 ms for, e.g., a High Speed Train (FIST)

scenario, etc.

N (Number of OFDM symbols per TRS within a slot)

^■ 1

■ 2 ^■ 4

B (TRS bandwidth in terms of number of RBs)

^■ ~24 RBs assuming smaller Subcarrier Spacing (SCS) = 15 kHz (FFS, for other SCS values)

^■ 50 RBs assuming SCS = 15 kHz

^■ Min(50 RBs, BWP), TRS cannot be received beyond the active BWP in frequency

^■ FFS for Wideband (WB) operation with multiple BWPs

S _f (TRS subcarrier spacing)

^■ 4

^■ 2

■ 6

^■ Note: not all the combinations of values for N, B, and S _f are

supported. Down selection in the next meeting.

S _t (TRS symbol spacing within a slot)

^■ Non-uniform ly spaced

^■ Uniformly spaced

^■ FFS on the values

[0019] There currently exist certain challenge(s). The UE requires reference signals to do time and/or frequency tracking in NR. However unlike in Long Term Evolution (LTE), in NR the reference signals are not transmitted in every subframe. Thus, there is a need for systems and methods for performing time and/or frequency tracking, e.g., in NR, where reference signals are not transmitted in every subframe.

Summary

[0020] Systems and methods for adapting the configuration of reference signals for timing and/or frequency synchronization related procedures are disclosed. In some embodiments, a method of operation of a wireless device in a wireless communication system comprises determining a configuration of one or more reference signals to be used by the wireless device for one or more timing and/or frequency synchronization related procedures with respect to a cell, wherein determining the configuration of the one or more reference signals comprises determining the configuration of the one or more reference signals based on an activity level of the wireless device. The method further comprises performing the one or more timing and/or frequency synchronization related procedures with respect to the cell using the one or more reference signals in accordance with the determined configuration.

[0021] In some embodiments, determining the configuration of the one or more reference signals is further based on a transmit timing accuracy

requirement on the wireless device, a speed of the wireless device, and/or a bandwidth or Bandwidth Part (BWP) of the wireless device.

[0022] In some embodiments, the one or more reference signals comprise a Tracking Reference Signal (TRS), a synchronization signal, and/or a

Demodulation Reference Signal (DMRS).

[0023] In some embodiments, the configuration of the one or more reference signals comprises a periodicity of the one or more reference signals, a bandwidth of the one or more reference signals, a transmit power of the one or more reference signals, a transmit power boosting of the one or more reference signals with respect to a reference level or with respect to another signal, a density of the one or more reference signals in time and/or frequency, a number of symbols per slot, and/or a number of slots with the one or more reference signals.

[0024] In some embodiments, the one or more timing and/or frequency related procedures comprise automatic gain control, time tracking, and/or frequency tracking.

[0025] In some embodiments, determining the configuration comprises determining the configuration further based on a message received from a network node and/or a predefined rule.

[0026] In some embodiments, determining the configuration comprises determining a value of a parameter T, wherein the wireless device is configured to receive the one or more reference signals within a time T prior to a beginning of wireless device activity of the wireless device. In some embodiments, the beginning of wireless device activity of the wireless device is a beginning of Discontinuous Reception (DRX) ON.

[0027] In some embodiments, determining the configuration of the one or more reference signals comprises determining the configuration of the one or more reference signals based on the activity level of the wireless device. In some embodiments, the activity level of the wireless device is a function of a DRX configuration of the wireless device and/or an extended DRX (eDRX) configuration of the wireless device. In some embodiments, the activity level of the wireless device is a function of a paging configuration of the wireless device, a Discontinuous Transmission (DTX) configuration of the wireless device, uplink transmissions of the wireless device, and/or a Radio Resource Control (RRC) state of the wireless device. In some embodiments, selecting a first configuration as the configuration of the one or more reference signals if the activity level of the wireless device is below a predefined or preconfigured threshold, and selecting a second configuration as the configuration of the one or more reference signals if the activity level of the wireless device is above a predefined or preconfigured threshold.

[0028] In some embodiments, determining the configuration of the one or more reference signals comprises determining the configuration of the one or more reference signals based on the transmit timing accuracy requirement on the wireless device. In some embodiments, determining the configuration comprises selecting a first configuration as the configuration of the one or more reference signals if the transmit timing accuracy requirement is less accurate than a predefined or preconfigured threshold, and selecting a second configuration as the configuration of the one or more reference signals if the transmit timing accuracy requirement is more accurate than a predefined or preconfigured threshold.

[0029] In some embodiments, determining the configuration of the one or more reference signals comprises determining the configuration of the one or more reference signals based on the speed of the wireless device. In some embodiments, determining the configuration comprises selecting a first configuration as the configuration of the one or more reference signals if the speed of the wireless device is less than a predefined or preconfigured threshold, and selecting a second configuration as the configuration of the one or more reference signals if the speed of the wireless device is more than a predefined or preconfigured threshold.

[0030] In some embodiments, determining the configuration of the one or more reference signals comprises determining the configuration of the one or more reference signals based on the bandwidth or BWP of the wireless device.

In some embodiments, determining the configuration comprises selecting a first configuration as the configuration of the one or more reference signals if the bandwidth or BWP of the wireless device is less than a predefined or

preconfigured threshold, and selecting a second configuration as the

configuration of the one or more reference signals if the bandwidth or BWP of the wireless device is more than a predefined or preconfigured threshold.

[0031] Embodiments of a wireless device are also disclosed. In some embodiments, a wireless device for operation in a wireless communication system comprises at least one transmitter, at least one receiver, and processing circuitry configured to cause the wireless device to determine a configuration of one or more reference signals to be used by the wireless device for one or more timing and/or frequency synchronization related procedures with respect to a cell. The configuration of the one or more reference signals is determined based on an activity level of the wireless device. The processing circuitry is further configured to cause the wireless device to perform the one or more timing and/or frequency synchronization related procedures with respect to the cell using the one or more reference signals in accordance with the determined configuration.

[0032] In some embodiments, the configuration of the one or more reference signals is further based on a transmit timing accuracy requirement on the wireless device, a speed of the wireless device, and/or a bandwidth or BWP of the wireless device. [0033] In some embodiments, in order to determine the configuration, the processing circuitry is further configured to cause the wireless device to determine the configuration of the one or more reference signals based on the activity level of the wireless device. In some embodiments, the activity level of the wireless device is a function of a DRX configuration of the wireless device and/or an eDRX configuration of the wireless device.

[0034] In some embodiments, in order to determine the configuration, the processing circuitry is further configured to determine the configuration of the one or more reference signals based on the bandwidth or BWP of the wireless device. In some embodiments, in order to determine the configuration of the one or more reference signals based on the bandwidth or BWP of the wireless device, the processing circuitry is further configured to cause the wireless device to select a first configuration as the configuration of the one or more reference signals if the bandwidth or BWP of the wireless device is less than a predefined or preconfigured threshold and select a second configuration as the configuration of the one or more reference signals if the bandwidth or BWP of the wireless device is more than a predefined or preconfigured threshold.

[0035] Embodiments of method of operation of a network node are also disclosed. In some embodiments, a method of operation of a network node in a wireless communication system comprises providing, to a wireless device, a configuration of one or more reference signals to be used by the wireless device for one or more timing and/or frequency synchronization related procedures with respect to a cell, wherein the configuration of the one or more reference signals is based on an activity level of the wireless device, a transmit timing accuracy requirement on the wireless device, a speed of the wireless device, and/or a bandwidth or BWP of the wireless device. In some embodiments, the method further comprises transmitting the one or more reference signals in accordance with the determined configuration.

[0036] In some embodiments, the one or more reference signals comprise a TRS, a synchronization signal, and/or a DMRS. [0037] In some embodiments, the configuration of the one or more reference signals comprises a periodicity of the one or more reference signals, a bandwidth of the one or more reference signals, a transmit power of the one or more reference signals, a transmit power boosting of the one or more reference signals with respect to a reference level or with respect to another signal, a density of the one or more reference signals in time and/or frequency, a number of symbols per slot, and/or a number of slots with the one or more reference signals.

[0038] In some embodiments, the one or more timing and/or frequency related procedures comprise automatic gain control, time tracking, and/or frequency tracking.

[0039] In some embodiments, the configuration comprises a value of a parameter T, wherein the wireless device is configured to receive the one or more reference signals within a time T prior to a beginning of wireless device activity of the wireless device. In some embodiments, the beginning of wireless device activity of the wireless device is a beginning of DRX ON.

[0040] In some embodiments, the configuration of the one or more reference signals is based on the activity level of the wireless device. In some

embodiments, the activity level of the wireless device is a function of a DRX configuration of the wireless device, an eDRX configuration of the wireless device, a paging configuration of the wireless device, a DTX configuration of the wireless device, uplink transmissions of the wireless device, and/or a RRC state of the wireless device.

[0041] In some embodiments, the configuration comprises a first configuration of the one or more reference signals if the activity level of the wireless device is below a predefined or preconfigured threshold and a second configuration of the one or more reference signals if the activity level of the wireless device is above a predefined or preconfigured threshold.

[0042] In some embodiments, the configuration of the one or more reference signals is based on the transmit timing accuracy requirement on the wireless device. In some embodiments, the configuration comprises a first configuration of the one or more reference signals if the transmit timing accuracy requirement is less accurate than a predefined or preconfigured threshold and a second configuration of the one or more reference signals if the transmit timing accuracy requirement is more accurate than a predefined or preconfigured threshold.

[0043] In some embodiments, the configuration of the one or more reference signals is based on the speed of the wireless device. In some embodiments, the configuration comprises a first configuration of the one or more reference signals if the speed of the wireless device is less than a predefined or preconfigured threshold and a second configuration of the one or more reference signals if the speed of the wireless device is more than a predefined or preconfigured threshold.

[0044] In some embodiments, the configuration of the one or more reference signals is based on the bandwidth or BWP of the wireless device. In some embodiments, the configuration comprises a first configuration of the one or more reference signals if the bandwidth or BWP of the wireless device is less than a predefined or preconfigured threshold and a second configuration of the one or more reference signals if the bandwidth or BWP of the wireless device is more than a predefined or preconfigured threshold.

[0045] Embodiments of a network node are also disclosed. In some embodiments, a network node for operation in a wireless communication system comprises at least one network interface and/or at least transmitter and/or at least one receiver. The network node further comprises processing circuitry configured to cause the network node to provide, to a wireless device, a configuration of one or more reference signals to be used by the wireless device for one or more timing and/or frequency synchronization related procedures with respect to a cell. The configuration of the one or more reference signals is based on an activity level of the wireless device, a transmit timing accuracy requirement on the wireless device, a speed of the wireless device, and/or a bandwidth or BWP of the wireless device. Brief Description of the Drawings

[0046] The accompanying drawing figures incorporated in and forming a part of this specification illustrate several aspects of the disclosure, and together with the description serve to explain the principles of the disclosure.

[0047] Figure 1 illustrates a New Radio (NR) architecture;

[0048] Figure 2 illustrates a number of NR deployment examples;

[0049] Figure 3 illustrates an example of hybrid beamforming;

[0050] Figures 4A and 4B illustrate an example of transmit beamforming on two subarrays and three subarrays, respectively;

[0051] Figure 5 illustrates an example configuration of Synchronization Signal (SS) blocks, SS bursts, and SS burst sets/series;

[0052] Figures 6A and 6B illustrate example mappings for SS blocks within a time slot and within a 5 millisecond (ms) window for different subcarrier spacings;

[0053] Figure 7 illustrates one example of a cellular communications network in which embodiments of the present disclosure may be implemented;

[0054] Figure 8 is a flow chart that illustrates the operation of a wireless device, or User Equipment (UE), according to some embodiments of the present disclosure;

[0055] Figure 9 is a flow chart that illustrates the operation of a network node (e.g., a radio access node) according to some embodiments of the present disclosure;

[0056] Figures 10 through 12 illustrate example embodiments of a radio access node;

[0057] Figures 13 and 14 illustrate example embodiments of a wireless device;

[0058] Figure 15 illustrates an example of a communication system in which embodiments of the present disclosure may be implemented;

[0059] Figure 16 illustrates an example embodiment of a UE, a base station, and a host computer in which embodiments of the present disclosure may be implemented; [0060] Figure 17 is a flowchart illustrating a method implemented in a communication system in accordance with an embodiment of the present disclosure;

[0061] Figure 18 is a flowchart illustrating a method implemented in a communication system in accordance with another embodiment of the present disclosure;

[0062] Figure 19 is a flowchart illustrating a method implemented in a communication system in accordance with another embodiment of the present disclosure; and

[0063] Figure 20 is a flowchart illustrating a method implemented in a communication system in accordance with another embodiment of the present disclosure.

Detailed Description

[0064] The embodiments set forth below represent information to enable those skilled in the art to practice the embodiments and illustrate the best mode of practicing the embodiments. Upon reading the following description in light of the accompanying drawing figures, those skilled in the art will understand the concepts of the disclosure and will recognize applications of these concepts not particularly addressed herein. It should be understood that these concepts and applications fall within the scope of the disclosure.

[0065] Generally, all terms used herein are to be interpreted according to their ordinary meaning in the relevant technical field, unless a different meaning is clearly given and/or is implied from the context in which it is used. All references to a/an/the element, apparatus, component, means, step, etc. are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any methods disclosed herein do not have to be performed in the exact order disclosed, unless a step is explicitly described as following or preceding another step and/or where it is implicit that a step must follow or precede another step. Any feature of any of the embodiments disclosed herein may be applied to any other embodiment, wherever appropriate. Likewise, any advantage of any of the embodiments may apply to any other embodiments, and vice versa. Other objectives, features, and advantages of the enclosed embodiments will be apparent from the following description.

[0066] In some embodiments a non-limiting term“User Equipment” or“UE” is used. The UE herein can be any type of wireless device capable of communicating with network node or another UE over radio signals. The UE may also be radio communication device, target device, Device-to-Device (D2D) UE, machine type UE or UE capable of Machine-to-Machine (M2M) communication, a sensor equipped with a UE, an iPad, a tablet, mobile terminals, a smart phone, Laptop Embedded Equipment (LEE), Laptop

Mounted Equipment (LME), Universal Serial Bus (USB) dongles, Customer Premise Equipment (CPE), etc.

[0067] Also in some embodiments generic terminology“network node” is used. It can be any kind of network node which may comprise of a radio network node such as a Base Station (BS), a radio BS, a base transceiver station, a BS controller, a network controller, a multi-standard radio BS, a New Radio (NR) Node B (gNB), a NR BS, an enhanced or evolved Node B (eNB), a Node B, a Multi-Cell/Multicast Coordination Entity (MCE), a relay node, an Access Point (AP), a radio AP, a Remote Radio Unit (RRU), a Remote Radio Head (RRH), a multi-standard BS (a.k.a. Multi-Standard Radio (MSR) BS), a core network node (e.g., a Mobility Management Entity (MME), a Self- Organizing Network (SON) node, a coordinating node, a positioning node, a Minimization of Drive Tests (MDT) node, etc.), or even an external node (e.g., a third party node, a node external to the current network), etc. The network node may also comprise test equipment.

[0068] The term“BS” may comprise, e.g., a gNB, eNB, or a relay node, or any BS compliant with the embodiments.

[0069] The term“radio node” used herein may be used to denote a UE or a radio network node. [0070] The term“signaling” used herein may comprise any of: high-layer signaling (e.g., via Radio Resource Control (RRC) or a like), lower-layer signaling (e.g., via a physical control channel or a broadcast channel), or a combination thereof. The signaling may be implicit or explicit. The signaling may further be unicast, multicast, or broadcast. The signaling may also be directly to another node or via a third node.

[0071] The term numerology here may comprise any one or a combination of: subcarrier spacing, number of subcarriers within a bandwidth, resource block size, symbol length, Cyclic Prefix (CP) length, etc. In one specific non- limiting example, numerology comprises subcarrier spacing of 7.5 kilohertz (kHz), 15 kHz, 30 kHz, 60 kHz, 120 kHz, or 240 kHz. In another example, numerology is the CP length which may be used with subcarrier spacing 30 kHz or larger.

[0072] There currently exist certain challenge(s). The UE requires reference signals to do time and/or frequency tracking in NR. However unlike in Long Term Evolution (LTE), in NR the reference signals are not transmitted in every subframe. A UE operating in Discontinuous Reception (DRX) needs reference signals before the DRX active time (e.g., DRX ON duration) when the UE is required to acquire the serving cell timing. Otherwise, the UE cannot receive the downlink control channel (e.g., Physical Downlink Control Channel (PDCCH)) during the DRX active time. Tracking Reference Signals (TRSs) are defined in NR for enabling the UE to do time tracking. However, the TRS configuration and DRX configuration for a UE are currently not related. This means that, in DRX and especially for the UE configured in long DRX (e.g., DRX cycle larger than 320 milliseconds (ms)), the UE reception quality (e.g., of the downlink control channel) will degrade during DRX active time, or the UE may not even be able to receive the downlink channel.

[0073] Certain aspects of the present disclosure and their embodiments may provide solutions to the aforementioned problems or other challenges. According to one embodiment, the configuration of reference signals (e.g., TRS

configuration) to be used for at least timing and/or frequency synchronization related procedures with respect to a cell (e.g., one of Automatic Gain Control (AGC), time and frequency tracking) for a UE is selected adaptively to the UE activity, e.g., based on one or more of:

• DRX configuration,

• Extended DRX (eDRX) configuration,

• Paging configuration,

• Discontinuous Transmission (DTX) configuration,

• Uplink transmissions (e.g., Physical Uplink Control Channel (PUCCH), Physical Uplink Shared Channel (PUSCH), Sounding Reference Signal (SRS), the first transmission after Random Access Channel (RACH) -less handover, or the Physical Random Access Channel (PRACH)

transmission),

• UE RRC state: RRCJDLE (low activity) vs. RRC_CONNECTED (high activity).

[0074] The mapping or association between the configuration of reference signals (e.g., TRS configuration) and the UE activity (e.g., DRX cycle

configuration) can be predefined and/or configured at the UE by the network node.

[0075] Certain embodiments may provide one or more of the following technical advantage(s). At least the following advantages may be envisioned:

• Accurate AGC, time, and frequency tracking can be achieved depending on the UE activity level.

• The reception quality of a downlink channel (e.g., downlink control

channel, downlink data channel, etc.) is enhanced especially for the UE operating in a longer DRX cycle.

• The overhead in terms of transmission of reference signals (e.g., TRS) for enabling the UE to acquire synchronization with respect to the serving cell is reduced.

[0076] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Other embodiments, however, are contained within the scope of the subject matter disclosed herein, and the disclosed subject matter should not be construed as limited to only the embodiments set forth herein; rather, these embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

[0077] Figure 7 illustrates one example of a cellular communications network 700 in which embodiments of the present disclosure may be implemented. In the embodiments described herein, the cellular communications network 700 is a Fifth Generation (5G) NR network. In this example, the cellular communications network 700 includes base stations 702-1 and 702-2, which in 5G NR are referred to as gNBs, controlling corresponding macro cells 704-1 and 704-2. The base stations 702-1 and 702-2 are generally referred to herein collectively as base stations 702 and individually as base station 702. Likewise, the macro cells 704-1 and 704-2 are generally referred to herein collectively as macro cells 704 and individually as macro cell 704. The cellular communications network 700 may also include a number of low power nodes 706-1 through 706-4 controlling corresponding small cells 708-1 through 708-4. The low power nodes 706-1 through 706-4 can be small base stations (such as pico or femto base stations) or RRHs, or the like. Notably, while not illustrated, one or more of the small cells 708-1 through 708-4 may alternatively be provided by the base stations 702.

The low power nodes 706-1 through 706-4 are generally referred to herein collectively as low power nodes 706 and individually as low power node 706. Likewise, the small cells 708-1 through 708-4 are generally referred to herein collectively as small cells 708 and individually as small cell 708. The base stations 702 (and optionally the low power nodes 706) are connected to a core network 710.

[0078] The base stations 702 and the low power nodes 706 provide service to wireless devices 712-1 through 712-5 in the corresponding cells 704 and 708. The wireless devices 712-1 through 712-5 are generally referred to herein collectively as wireless devices 712 and individually as wireless device 712. The wireless devices 712 are also sometimes referred to herein as UEs. Methods in a UE

[0079] According to one embodiment, the configuration of signals (e.g., TRS, etc.) to be used by a wireless device 712 (also referred to herein as a UE 712) for at least timing and/or frequency synchronization related procedures in the UE 712 with respect to a first cell (celH ) is adaptively determined or selected for the UE 712 based on a UE activity level of the UE 712. Examples of celH are a Primary Cell (PCell), a Primary Secondary Cell (PSCell), a Secondary Cell (SCell), etc.

[0080] Examples of timing and/or frequency synchronization related procedures are: AGC, time, and frequency tracking. The associated reference signals used by the UE 712 for AGC, time, and frequency tracking herein are called AGC, Time, and Frequency Tracking Reference Signals (ATFRSs).

ATFRSs are types of reference signals which the UE 712 can use for timing and/or frequency synchronization related procedures in the UE 712 with respect to celll Examples of ATFRSs are TRSs, Synchronization Signals (SSs) (e.g., SS signals in a SS block), Demodulation Reference Signals (DMRSs), etc. The ATFRSs may further comprise transmission parameters associated with the reference signals, e.g. periodicity of reference signals, Bandwidth (BW) of the reference signals, transmit power or transmit power boosting with respect to a reference level or with respect to another signal, density of the signal in time and/or frequency, number of symbols per slot, number of slots with the signal, etc.

[0081] The UE activity level is defined by one or more criteria or parameters. Examples of such criteria or parameters defining the UE activity level are, e.g., one or more of:

• DRX configuration,

• eDRX configuration,

• Paging configuration,

• DTX configuration,

• Uplink transmissions (e.g., PUCCFI, PUSCFI, SRS, the first transmission after RACFI-less handover, or the PRACFI transmission), • UE RRC state: RRCJDLE (low activity) vs. RRC_CONNECTED (high activity).

[0082] The configuration may be based on a message received from a network node and/or based on a predefined rule (e.g., requirement in the standard or predefined UE behavior).

[0083] The ATFRS may be configured to be received by the UE 712 within a predefined time T prior to the beginning of the UE activity (e.g., DRX ON). T may be a function of the UE activity level, e.g., can be shorter when the UE activity is higher (e.g., DRX cycle length is below a threshold).

[0084] Based on the configured ATFRS, the UE 712 may be expected to meet one or more predefined performance requirements, e.g., timing and/or frequency synchronization accuracy, transmit timing accuracy, PDCCFI performance, etc.

[0085] The above embodiments are further described by means of several examples:

• The UE 712 is configured to receive the ATFRS based on a first

configuration when the UE activity is low or below a threshold and based on a second configuration when the UE activity is high or above a threshold. As an example, the UE activity is low if the UE 712 receives and/or transmits signals less than 10% of the time; otherwise the UE activity is considered to be high.

• The UE 712 is configured to receive the ATFRS based on a first

configuration when the UE transmit timing accuracy requirement is more relaxed (e.g., less accurate) and based on a second configuration when the UE transmit timing accuracy is tighter (e.g., more accurate). An example of relaxed UE transmit timing accuracy is ± 640 To with regard to the downlink timing of the serving cell. An example of tighter UE transmit timing accuracy is less than the magnitude of ± 640 To with regard to the downlink timing of the serving cell. Where for example 1 To = 32.55/64 nanoseconds (ns).

• The UE 712 is configured to receive the ATFRS based on a first

configuration when the UE speed is low or below a threshold and based on a second configuration when the UE speed is high or above a threshold. The UE speed can be expressed in terms of distance per unit time (e.g., X1 km/hour) and/or in terms of Doppler frequency (e.g., X2 hertz (Hz)). As an example the UE speed is low if the UE speed is less than 30 kilometer per hour (km/hour); otherwise the UE speed is considered to be high.

• The UE 712 is configured to receive the ATFRS based on a first

configuration when the UE BW and/or BW Part (BWP) is below a threshold and based on a second configuration otherwise.

[0086] A UE 712 may be considered as operating with a lower UE activity level when one or more of the following conditions are met, e.g.:

• UE DRX or eDRX cycle length is above a threshold,

• UE is configured with eDRX (compared to when configured with DRX or no DRX),

• UE is transmitting less frequently or not at all, e.g. with a duty cycle of less than 10%,

• UE’s paging occasion occurs less frequently (paging period length is

above a threshold),

• UE is actually receiving paging less frequently, e.g. only in less than 5% of the paging occasions,

• UE is operating in IDLE (compared to CONNECTED),

• UE is operating with a Subcarrier Spacing (SCS) and longer symbols (vs. larger SCS and shorter symbols), etc. Examples of smaller SCS are 15 kHz and 30 kHz. Examples of larger SCS are 60 kHz, 120 kHz, and 240 kHz. Examples of larger symbol lengths are 71 microseconds (ps),

• UE speed is below a threshold (vs. high-speed UEs which can be referred to as a higher activity since the need to perform certain operations faster)

[0087] The first configuration vs. the second configuration may comprise one or more of:

• Longer TRS burst and/or larger number of Orthogonal Frequency Division Multiplexing (OFDM) symbols within a slot • Longer TRS burst periodicity

• Longer TRS symbol spacing within a slot

• Larger bandwidth (e.g., to compensate with sparse in time ATFRS

occasions for a low-activity UE)

• Smaller bandwidth for UEs with a speed below a threshold and larger bandwidth for high-speed UEs

• A different type of ATFRS (e.g., SS/Physical Broadcast Channel (PBCH) block when the activity is low or below a threshold and TRS when the activity is high or above a threshold; SS/PBCH block when the UE BW and/or BWP is below a threshold and TRS when the UE BW and/or BWP are above a threshold)

• A different number of ATFRSs (e.g., SS/PBCH block and TRS for

CONNECTED mode but only SS/PBCH block for IDLE; SS/PBCH block and TRS when more accurate UE transmit timing is needed vs. only SS/PBCH block or only TRS when less accurate UE transmit timing is needed)

• Higher transmit power for ATFRS may be considered to enable faster time/frequency tracking which may be beneficial, e.g., for high-speed UEs or for UEs with long DRX cycles (to compensate for sparse ATFRS occasions)

• In one example of the rule, the UE shall assume that whether a first type of reference signals (RS1 ) (e.g., TRS) for time tracking in a cell (e.g., serving cell) are available at the UE as ATFRS depends on the

configuration of a second type of reference signals (RS2) (e.g., Primary Synchronization Signal (PSS) / Secondary Synchronization Signal (SSS), DMRS in SS/PBCH block, etc.). For example, the UE assumes that whether RS1 is available at the UE or not for time tracking in the cell depends on periodicity of the RS2. For example, the UE assumes that RS1 is available at the UE provided that the periodicity of the RS2 is larger than certain threshold, e.g. 80 ms. • In another example of the rule, the UE shall assume that whether RS1 (e.g., TRS) for time tracking in the cell (e.g., serving cell) are available at the UE as ATFRS depends on the configuration of RS2 (e.g., PSS/SSS, DMRS in SS/PBCH block, etc.) as well as the configuration of the UE DRX cycle. For example, the UE assumes that whether RS1 is available at the UE or not for time tracking in the cell depends on the periodicities of both RS2 and the UE DRX cycle. For example, the UE assumes that RS1 is available at the UE provided that the periodicity of the RS2 is larger than a certain threshold, e.g. 80 ms, and also the DRX cycle is larger than a certain threshold. This is further elaborated with more specific examples below.

• In one specific example of the rule, if the UE DRX cycle is shorter than a certain DRX threshold (H 1 ) then the UE shall assume that the signals (e.g., SS, DMRS) in the SS/PBCFI block are available as ATFRS.

Otherwise, if the DRX cycle is larger than or equal to H 1 , then the UE shall assume that TRSs are available as ATFRS. This rule can also be associated with the UE RRC state, e.g., in RRC connected state.

• In another specific example of the rule, if the UE DRX cycle is longer than a certain DRX threshold (H2) (e.g., H 1 is 640 ms) and if SS/PBCFI is sent at least once every Z1 ms (e.g., Z1 = 20 ms) then the UE shall assume signals in SS/PBCFI are available as ATFRS; otherwise, if the DRX cycle is longer than FH 1 but SS/PBCFI is sent with periodicity longer than Z1 ms (e.g., Z1 = 20 ms), then the UE shall assume that TRSs are also available as ATFRS. This rule can also be associated with the UE RRC state, e.g., in RRC idle state.

• Based on one or more examples of rules, the UE shall determine the type of reference signals (type of ATFRS) which the UE can apply for doing operations such as AGC, time, and/or frequency tracking. The UE then uses the determined signals for performing operations such as AGC, time, and/or frequency tracking with regard to the cell, e.g. serving cell such as PCell, PSCell, SCell, etc. The above rules require the network node to transmit the relevant reference signals (type of ATFRS) in the cell based on, e.g., the configuration of DRX cycle, configuration of RS2, etc.

[0088] The UE 712, upon determining the available ATFRS, uses the determined reference signals (e.g., SS, DMRS, TRS, Channel State Information Reference Signal (CSI-RS), etc.) for performing the timing and/or frequency synchronization related tasks with regard to the cell, e.g. PCell, PSCell, etc. Examples of SS signals are PSS and SSS. This enables the UE 712 to adapt its receiver with regard to the cell and therefore further enable the UE 712 to receive signals from the cell, e.g., PDCCFI, Physical Downlink Shared Channel

(PDSCH), etc.

[0089] Figure 8 is a flow chart that illustrates the operation of a wireless device 712, or UE 712, according to at least some of the embodiments described above. As illustrated, the wireless device 712 determines a configuration of one or more reference signals to be used by the wireless device for one or more timing and/or frequency synchronization related procedures with respect to a cell (step 800). This determination is based on an activity level of the wireless device 712, a transmit timing accuracy requirement on the wireless device 712, a speed of the wireless device 712, and/or a BW or BWP of the wireless device 712, as described above. As described above, in some embodiments, the one or more reference signals comprise a TRS, a synchronization signal, and/or a DMRS. In some embodiments, the configuration of the one or more reference signals comprises a periodicity of the one or more reference signals, a BW of the one or more reference signals, a transmit power of the one or more reference signals, a transmit power boosting of the one or more reference signals with respect to a reference level or with respect to another signal, a density of the one or more reference signals in time and/or frequency, a number of symbols per slot, and/or a number of slots with the one or more reference signals. The wireless device 712 performs the one or more timing and/or frequency synchronization related procedures with respect to the cell using the one or more reference signals in accordance with the determined configuration (step 802). As described above, examples of the one or more timing and/or frequency related procedures comprise AGC, time tracking, and/or frequency tracking. Additional details of this process are described above and therefore not repeated here.

Methods in a Network Node

[0090] A network node (e.g., a radio access node 702 or 706) may configure ATFRS for one or more UEs 712, based on the UE activity, which may be described by one or more of:

• DRX configuration,

• eDRX configuration,

• Paging configuration,

• DTX configuration,

• Uplink transmissions (e.g., PUCCH, PUSCH, SRS, the first transmission after RACH-less handover, or the PRACH transmission),

• UE RRC state: RRCJDLE (low activity) vs. RRC_CONNECTED (high activity).

[0091] The configuring rules are the same as described in the Methods in a UE section above.

[0092] A network node may also configure the same ATFRS transmissions for more than one UE, based on their similar activity level, and thereby perform grouping of UEs, e.g., the same configuration for all UEs in IDLE, the same configuration for all UEs with DRX cycle of X, the same configuration for UEs with aligned DRX ON, etc. The network node would further signal the same ATFRS configuration to the group of UEs.

[0093] Figure 9 is a flow chart that illustrates the operation of a network node (e.g., a radio access node 702 or 706) in accordance with at least some of the embodiments described above. As illustrated, the network node provides, to a wireless device 712, a configuration of one or more reference signals to be used by the wireless device 712 for one or more timing and/or frequency

synchronization related procedures with respect to a cell (step 900). The configuration of the one or more reference signals is based on an activity level of the wireless device 712, a transmit timing accuracy requirement on the wireless device 712, a speed of the wireless device 712, and/or a BW or BWP of the wireless device 712, as described above. As described above, in some embodiments, the one or more reference signals comprise a TRS, a SS, and/or a DMRS. In some embodiments, the configuration of the one or more reference signals comprises a periodicity of the one or more reference signals, a bandwidth of the one or more reference signals, a transmit power of the one or more reference signals, a transmit power boosting of the one or more reference signals with respect to a reference level or with respect to another signal, a density of the one or more reference signals in time and/or frequency, a number of symbols per slot, and/or a number of slots with the one or more reference signals. As described above, examples of the one or more timing and/or frequency related procedures comprise AGC, time tracking, and/or frequency tracking. Optionally (as indicated by the dashed lines), the network node transmits the one or more reference signals in accordance with the determined configuration (step 902). Additional details of this process are described above and therefore not repeated here.

Additional Details

[0094] Figure 10 is a schematic block diagram of a radio access node 1000 according to some embodiments of the present disclosure. The radio access node 1000 may be, for example, a base station 702 or 706. As illustrated, the radio access node 1000 includes a control system 1002 that includes one or more processors 1004 (e.g., Central Processing Units (CPUs), Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), and/or the like), memory 1006, and a network interface 1008. In addition, the radio access node 1000 includes one or more radio units 1010 that each includes one or more transmitters 1012 and one or more receivers 1014 coupled to one or more antennas 1016. In some embodiments, the radio unit(s) 1010 is external to the control system 1002 and connected to the control system 1002 via, e.g., a wired connection (e.g., an optical cable). Flowever, in some other embodiments, the radio unit(s) 1010 and potentially the antenna(s) 1016 are integrated together with the control system 1002. The one or more processors 1004 operate to provide one or more functions of a radio access node 1000 as described herein. In some embodiments, the function(s) are implemented in software that is stored, e.g., in the memory 1006 and executed by the one or more processors 1004.

[0095] Figure 11 is a schematic block diagram that illustrates a virtualized embodiment of the radio access node 1000 according to some embodiments of the present disclosure. This discussion is equally applicable to other types of network nodes. Further, other types of network nodes may have similar virtualized architectures.

[0096] As used herein, a“virtualized” radio access node is an implementation of the radio access node 1000 in which at least a portion of the functionality of the radio access node 1000 is implemented as a virtual component(s) (e.g., via a virtual machine(s) executing on a physical processing node(s) in a network(s)).

As illustrated, in this example, the radio access node 1000 includes the control system 1002 that includes the one or more processors 1004 (e.g., CPUs, ASICs, FPGAs, and/or the like), the memory 1006, and the network interface 1008 and the one or more radio units 1010 that each includes the one or more transmitters 1012 and the one or more receivers 1014 coupled to the one or more antennas 1016, as described above. The control system 1002 is connected to the radio unit(s) 1010 via, for example, an optical cable or the like. The control system 1002 is connected to one or more processing nodes 1100 coupled to or included as part of a network(s) 1102 via the network interface 1008. Each processing node 1100 includes one or more processors 1104 (e.g., CPUs, ASICs, FPGAs, and/or the like), memory 1106, and a network interface 1108.

[0097] In this example, functions 1110 of the radio access node 1000 described herein are implemented at the one or more processing nodes 1100 or distributed across the control system 1002 and the one or more processing nodes 1100 in any desired manner. In some particular embodiments, some or all of the functions 1110 of the radio access node 1000 described herein are implemented as virtual components executed by one or more virtual machines implemented in a virtual environment(s) hosted by the processing node(s) 1100. As will be appreciated by one of ordinary skill in the art, additional signaling or communication between the processing node(s) 1100 and the control system 1002 is used in order to carry out at least some of the desired functions 1110. Notably, in some embodiments, the control system 1002 may not be included, in which case the radio unit(s) 1010 communicates directly with the processing node(s) 1100 via an appropriate network interface(s).

[0098] In some embodiments, a computer program including instructions which, when executed by at least one processor, causes the at least one processor to carry out the functionality of radio access node 1000 or a node (e.g., a processing node 1100) implementing one or more of the functions 1110 of the radio access node 1000 in a virtual environment according to any of the embodiments described herein is provided. In some embodiments, a carrier comprising the aforementioned computer program product is provided. The carrier is one of an electronic signal, an optical signal, a radio signal, or a computer readable storage medium (e.g., a non-transitory computer readable medium such as memory).

[0099] Figure 12 is a schematic block diagram of the radio access node 1000 according to some other embodiments of the present disclosure. The radio access node 1000 includes one or more modules 1200, each of which is implemented in software. The module(s) 1200 provide the functionality of the radio access node 1000 described herein. This discussion is equally applicable to the processing node 1100 of Figure 11 where the modules 1200 may be implemented at one of the processing nodes 1100 or distributed across multiple processing nodes 1100 and/or distributed across the processing node(s) 1100 and the control system 1002.

[0100] Figure 13 is a schematic block diagram of a UE 1300 according to some embodiments of the present disclosure. As illustrated, the UE 1300 includes one or more processors 1302 (e.g., CPUs, ASICs, FPGAs, and/or the like), memory 1304, and one or more transceivers 1306 each including one or more transmitters 1308 and one or more receivers 1310 coupled to one or more antennas 1312. In some embodiments, the functionality of the UE 1300 described above may be fully or partially implemented in software that is, e.g., stored in the memory 1304 and executed by the processor(s) 1302.

[0101] In some embodiments, a computer program including instructions which, when executed by at least one processor, causes the at least one processor to carry out the functionality of the UE 1300 according to any of the embodiments described herein is provided. In some embodiments, a carrier comprising the aforementioned computer program product is provided. The carrier is one of an electronic signal, an optical signal, a radio signal, or a computer readable storage medium (e.g., a non-transitory computer readable medium such as memory).

[0102] Figure 14 is a schematic block diagram of the UE 712 according to some other embodiments of the present disclosure. The UE 712 includes one or more modules 1400, each of which is implemented in software. The module(s) 1400 provide the functionality of the UE 712 described herein.

[0103] With reference to Figure 15, in accordance with an embodiment, a communication system includes a telecommunication network 1500, such as a 3GPP-type cellular network, which comprises an access network 1502, such as a Radio Access Network (RAN), and a core network 1504. The access network 1502 comprises a plurality of base stations 1506A, 1506B, 1506C, such as Node Bs, eNBs, gNBs, or other types of wireless APs, each defining a corresponding coverage area 1508A, 1508B, 1508C. Each base station 1506A, 1506B, 1506C is connectable to the core network 1504 over a wired or wireless connection 1510. A first UE 1512 located in coverage area 1508C is configured to wirelessly connect to, or be paged by, the corresponding base station 1506C. A second UE 1514 in coverage area 1508A is wirelessly connectable to the corresponding base station 1506A. While a plurality of UEs 1512, 1514 are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding base station 1506.

[0104] The telecommunication network 1500 is itself connected to a host computer 1516, which may be embodied in the hardware and/or software of a standalone server, a cloud-implemented server, a distributed server, or as processing resources in a server farm. The host computer 1516 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. Connections 1518 and 1520 between the telecommunication network 1500 and the host computer 1516 may extend directly from the core network 1504 to the host computer 1516 or may go via an optional intermediate network 1522. The intermediate network 1522 may be one of, or a combination of more than one of, a public, private, or hosted network; the intermediate network 1522, if any, may be a backbone network or the Internet; in particular, the intermediate network 1522 may comprise two or more sub-networks (not shown).

[0105] The communication system of Figure 15 as a whole enables

connectivity between the connected UEs 1512, 1514 and the host computer 1516. The connectivity may be described as an Over-the-Top (OTT) connection 1524. The host computer 1516 and the connected UEs 1512, 1514 are configured to communicate data and/or signaling via the OTT connection 1524, using the access network 1502, the core network 1504, any intermediate network 1522, and possible further infrastructure (not shown) as intermediaries. The OTT connection 1524 may be transparent in the sense that the participating

communication devices through which the OTT connection 1524 passes are unaware of routing of uplink and downlink communications. For example, the base station 1506 may not or need not be informed about the past routing of an incoming downlink communication with data originating from the host computer 1516 to be forwarded (e.g., handed over) to a connected UE 1512. Similarly, the base station 1506 need not be aware of the future routing of an outgoing uplink communication originating from the UE 1512 towards the host computer 1516.

[0106] Example implementations, in accordance with an embodiment, of the UE, base station, and host computer discussed in the preceding paragraphs will now be described with reference to Figure 16. In a communication system 1600, a host computer 1602 comprises hardware 1604 including a communication interface 1606 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of the communication system 1600. The host computer 1602 further comprises processing circuitry 1608, which may have storage and/or processing capabilities. In particular, the processing circuitry 1608 may comprise one or more programmable processors, ASICs, FPGAs, or combinations of these (not shown) adapted to execute instructions. The host computer 1602 further comprises software 1610, which is stored in or accessible by the host computer 1602 and executable by the processing circuitry 1608. The software 1610 includes a host application 1612. The host application 1612 may be operable to provide a service to a remote user, such as a UE 1614 connecting via an OTT connection 1616 terminating at the UE 1614 and the host computer 1602. In providing the service to the remote user, the host application 1612 may provide user data which is transmitted using the OTT connection 1616.

[0107] The communication system 1600 further includes a base station 1618provided in a telecommunication system and comprising hardware 1620 enabling it to communicate with the host computer 1602 and with the UE 1614. The hardware 1620 may include a communication interface 1622 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 1600, as well as a radio interface 1624 for setting up and maintaining at least a wireless connection 1626 with the UE 1614 located in a coverage area (not shown in Figure 16) served by the base station 1618. The communication interface 1622 may be configured to facilitate a connection 1628 to the host computer 1602. The connection 1628 may be direct or it may pass through a core network (not shown in Figure 16) of the telecommunication system and/or through one or more intermediate networks outside the telecommunication system. In the embodiment shown, the hardware 1620 of the base station 1618 further includes processing circuitry 1630, which may comprise one or more programmable processors, ASICs, FPGAs, or combinations of these (not shown) adapted to execute instructions. The base station 1618 further has software 1632 stored internally or accessible via an external connection. [0108] The communication system 1600 further includes the UE 1614 already referred to. The UE’s 1614 hardware 1634 may include a radio interface 1636 configured to set up and maintain a wireless connection 1626 with a base station serving a coverage area in which the UE 1614 is currently located. The hardware 1634 of the UE 1614 further includes processing circuitry 1638, which may comprise one or more programmable processors, ASICs, FPGAs, or combinations of these (not shown) adapted to execute instructions. The UE 1614 further comprises software 1640, which is stored in or accessible by the UE 1614 and executable by the processing circuitry 1638. The software 1640 includes a client application 1642. The client application 1642 may be operable to provide a service to a human or non-human user via the UE 1614, with the support of the host computer 1602. In the host computer 1602, the executing host application 1612 may communicate with the executing client application 1642 via the OTT connection 1616 terminating at the UE 1614 and the host computer 1602. In providing the service to the user, the client application 1642 may receive request data from the host application 1612 and provide user data in response to the request data. The OTT connection 1616 may transfer both the request data and the user data. The client application 1642 may interact with the user to generate the user data that it provides.

[0109] It is noted that the host computer 1602, the base station 1618, and the UE 1614 illustrated in Figure 16 may be similar or identical to the host computer 1516, one of the base stations 1506A, 1506B, 1506C, and one of the UEs 1512, 1514 of Figure 15, respectively. This is to say, the inner workings of these entities may be as shown in Figure 16 and independently, the surrounding network topology may be that of Figure 15.

[0110] In Figure 16, the OTT connection 1616 has been drawn abstractly to illustrate the communication between the host computer 1602 and the UE 1614 via the base station 1618 without explicit reference to any intermediary devices and the precise routing of messages via these devices. The network

infrastructure may determine the routing, which may be configured to hide from the UE 1614 or from the service provider operating the host computer 1602, or both. While the OTT connection 1616 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).

[0111] The wireless connection 1626 between the UE 1614 and the base station 1618 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the UE 1614 using the OTT connection 1616, in which the wireless connection 1626 forms the last segment. More precisely, the teachings of these embodiments may improve the performance of the radio access network (e.g., in terms of latency) and thereby provide benefits such as, e.g., reduced user waiting time, better responsiveness, and/or extended battery lifetime.

[0112] A measurement procedure may be provided for the purpose of monitoring data rate, latency, and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 1616 between the host computer 1602 and the UE 1614, in response to variations in the measurement results. The

measurement procedure and/or the network functionality for reconfiguring the OTT connection 1616 may be implemented in the software 1610 and the hardware 1604 of the host computer 1602 or in the software 1640 and the hardware 1634 of the UE 1614, or both. In some embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 1616 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which the software 1610, 1640 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 1616 may include message format, retransmission settings, preferred routing, etc.; the reconfiguring need not affect the base station 1614, and it may be unknown or imperceptible to the base station 1614. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling facilitating the host computer 1602’s measurements of throughput, propagation times, latency, and the like. The measurements may be

implemented in that the software 1610 and 1640 causes messages to be transmitted, in particular empty or‘dummy’ messages, using the OTT connection 1616 while it monitors propagation times, errors, etc.

[0113] Figure 17 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The

communication system includes a host computer, a base station, and a UE which may be those described with reference to Figures 15 and 16. For simplicity of the present disclosure, only drawing references to Figure 17 will be included in this section. In step 1700, the host computer provides user data. In sub-step 1702 (which may be optional) of step 1700, the host computer provides the user data by executing a host application. In step 1704, the host computer initiates a transmission carrying the user data to the UE. In step 1706 (which may be optional), the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 1708 (which may also be optional), the UE executes a client application associated with the host application executed by the host computer.

[0114] Figure 18 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The

communication system includes a host computer, a base station, and a UE which may be those described with reference to Figures 15 and 16. For simplicity of the present disclosure, only drawing references to Figure 18 will be included in this section. In step 1800 of the method, the host computer provides user data.

In an optional sub-step (not shown) the host computer provides the user data by executing a host application. In step 1802, the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In step 1804 (which may be optional), the UE receives the user data carried in the transmission. [0115] Figure 19 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The

communication system includes a host computer, a base station, and a UE which may be those described with reference to Figures 15 and 16. For simplicity of the present disclosure, only drawing references to Figure 19 will be included in this section. In step 1900 (which may be optional), the UE receives input data provided by the host computer. Additionally or alternatively, in step 1902, the UE provides user data. In sub-step 1904 (which may be optional) of step 1900, the UE provides the user data by executing a client application. In sub-step 1906 (which may be optional) of step 1902, the UE executes a client application which provides the user data in reaction to the received input data provided by the host computer. In providing the user data, the executed client application may further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the UE initiates, in sub-step 1908 (which may be optional), transmission of the user data to the host computer. In step 1910 of the method, the host computer receives the user data transmitted from the UE, in accordance with the teachings of the embodiments described throughout this disclosure.

[0116] Figure 20 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The

communication system includes a host computer, a base station, and a UE which may be those described with reference to Figures 15 and 16. For simplicity of the present disclosure, only drawing references to Figure 20 will be included in this section. In step 2000 (which may be optional), in accordance with the teachings of the embodiments described throughout this disclosure, the base station receives user data from the UE. In step 2002 (which may be optional), the base station initiates transmission of the received user data to the host computer. In step 2004 (which may be optional), the host computer receives the user data carried in the transmission initiated by the base station.

[0117] Any appropriate steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more virtual apparatuses. Each virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more

microprocessor or microcontrollers, as well as other digital hardware, which may include Digital Signal Processors (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as Read Only Memory (ROM), Random Access Memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions according one or more embodiments of the present disclosure.

[0118] While processes in the figures may show a particular order of operations performed by certain embodiments of the invention, it should be understood that such order is exemplary (e.g., alternative embodiments may perform the operations in a different order, combine certain operations, overlap certain operations, etc.).

Example Implementation of At Least Some Aspects of the Present Disclosure in

3GPP NR Specifications

1. Introduction

[0119] In NR the measurement requirements will be defined with and without DRX. Until now RAN4 has mainly focused on requirements without DRX based on simulation results which are obtained in non-DRX.

[0120] In this section, we address DRX related issues and also analyse the measurement requirements in DRX in NR. 2. Definition of DRX and non-DRX

[0121] Since requirements are being specified in non-DRX and also in DRX, therefore it is important that both these terms are well defined in TS 38.133. The non DRX implies the time during which the UE receiver is required to be active (ON) for receiving e.g. DL control channel.

[0122] In section 5.7 of TS 38.321 V1.0.0, the active time when DRX is configured is defined as follows:

When a DRX cycle is configured, the Active Time includes the time while:

drx-onDurationTimer or drx-InactivityTimer or drx-RetransmissionTimerDL or drx- RetransmissionTimerUL or ra-ContentionResolutionTimer (as described in subclause 5.1.5) is running; or

a Scheduling Request is sent on PUCCH and is pending (as described in subclause 5.4.4); or a PDCCH indicating a new transmission addressed to the C-RNTI of the MAC entity has not been received after successful reception of a Random Access Response for the preamble not selected by the MAC entity (as described in subclause 5.1.4).

Editor's note: Editor thinks the definition for the Active Time in LTE can be re-used, but RAN2 confirmation requires.

[0123] Based on the RAN2 definition of the active time, the states when no DRX is used and the DRX is used can be defined as follows.

For the requirements in RRC connected state specified in this version of the specification (TS 38.133), the UE shall assume that no DRX is used provided the following conditions are met:

DRX parameters are not configured or

DRX parameters are configured and

drx-onDurationTimer is runing or

drx-InactivityTimer is running or

drx-RetransmissionTimerDL is running or

drx-RetransmissionTimerUL is running or

ra-ContentionResolutionTimer is running or

a Scheduling Request sent on PUCCH is pending or

- a PDCCH indicating a new transmission addressed to the C-RNTI of the MAC entity has not been received after successful reception of a Random Access Response for the preamble not selected by the MAC entity Otherwise the UE shall assume that DRX is used.

[0124] Proposal 1 : Definition of the states when no DRX is used and when the DRX is used shall be defined in TS 38.133.

3. Time tracking in DRX

[0125] Especially in long DRX cycle the UE needs to wake up before the start of the DRX active time (e.g. in DRX ON duration) to perform time and/or frequency tracking in order to be able to receive DL control channel. In LTE the CRS are transmitted in every subframe. This allows the UE to perform time tracking using the CRS anytime before the DRX active time.

[0126] But in NR the UE will have to perform the time tracking based on PSS/SSS and DMRS within the SS/PBCH block. The is configured with SMTC configuration, which provides the occasion of the occurrence of the SS/PBCH block. The SMTC periodicity can be any of 5 ms, 10 ms, 20 ms, 40 ms , 80 ms or 160 ms. For shorter SMTC periodicity like up to 20 or 40 ms the UE can perform time tracking based on SS/PBCH block without any major impact on the UE power consumption. But when configured with longer SMTC periodicity (e.g. 80 or 160 ms) and also relatively longer DRX cycle then the UE may have to wake up well before the DRX on duration. It is not expected that the DRX cycle on duration and SMTC occasion are always aligned.

[0127] A tracking reference signal (TRS) are specified in section 7.4.1.6 of TS 38.211 v1.1.1. It is up to the network when the TRS are configured. We therefore suggest that the UE shall assume that TRS are available at the UE before the DRX on only when both SMTC periodicity and DRX cycles are longer e.g. SMTC periodicity > 80 ms and DRX cycle > 1280 ms. In other cases the UE shall not assume that TRS are also available at the UE. However it is up to the network whether it also configures TRS when the UE is configured with shorter DRX cycles or SMTC periodicity. [0128] Proposal 2: To enable time tracking in DRX the UE shall assume that TRS are available at the UE before the DRX ON provided that the SMTC periodicity > 80 ms and DRX cycle > 1280 ms. 4. RRM Requirements in DRX

[0129] RAN2 is defining the same ranges of the DRX cycles for NR as specified in LTE. This means the DRX cycles shall vary between 2 ms to 2560 ms in NR. RAN4 will have to define the RRM requirements for all the DRX cycles which are being defined in RAN2 for the NR. The SS/PBCH based RLM and even intra-frequency measurements are being defined with and without measurement gaps. Table 1 provides summary of parameters and their ranges which will impact the NR measurement/evaluation time for SS/PBCH based procedures (RLM/measurements) when DRX is used. Table 1 : Measurement Requirements

[0130] Therefore NR requirements in DRX can be function of the following parameters depending on the type of requirements as described in the next section: • DRX cycle length (T _DRX )

• SMTC periodicity (T _S MTC)

• Measurement gap periodicity (T _gap ) (if gaps are used)

• SCell measurement cycle (Tsceiicycie) (for SCC with deactivated SCell)

4.1 RLM requirements in DRX

[0131] Table 2 provides general function to specify the out of sync (OOS) and in sync (IS) evaluation periods for SS/PBCH based RLM on NR PSCell in DRX with and without gaps. The parameters K1 and K2 are constant multipliers representing the number of SMTC occasions needed for the RLM. Their values will be different for OOS and IS. The parameter G1 is the gap sharing parameter for sharing gaps between intra- and inter-frequency measurements. G1 may also include number of intra-frequency carriers (e.g. NR PSC, NR SCC etc) used for NR measurements including RLM.

Table 2: RLM Requirements for NR PSCell in DRX

4.2 Intra-frequency measurement requirements in DRX

[0132] Table 3 provides general function to specify the measurement time (e.g. L1 period and cell identification delay) for SS/PBCH based measurements on cells of NR PSC without gaps and NR SCC in DRX with and without gaps. In case of measurements on SCC with deactivated SCell the requirements also depend on the SCell measurement cycle. The parameters L1 , L2, L3 and L4 are constant multipliers representing the number of SMTC occasions needed for the measurements. Their values will be different for L1 measurement period and for cell identification delay. The parameter G1 is the same as used in RLM may also include number of intra-frequency carriers (e.g. NR PSC, NR SCC etc) used for NR measurements.

[0133] In case of measurements on SCC with deactivated SCell with DRXm the MAX (.) includes only DRX cycle and SCell measurement cycle since other parameters (SMTC and gap periodicities) can never exceed the SCell measurement cycle.

Table 3: Measurement Requirements for NR Intra-frequency Measurements in DRX

4.3 Inter-frequency measurement requirements in DRX

[0134] Table 4 provides general function to specify the measurement time (e.g. L1 period and cell identification delay) for SS/PBCH based NR inter- frequency measurements in DRX with gaps. The parameter M1 is a constant multiplier representing the number of SMTC occasions needed for the inter- frequency measurements. Its value will be different for L1 measurement period and for cell identification delay. The parameter G2 is the gap sharing parameter for sharing gaps between intra- and inter-frequency measurements. G2 also includes the total number of non-serving carriers configured for measurements. Table 4: Measurement Requirements for NR Inter-frequency Measurements in DRX

5 Summary

[0135] In this section we have discussed the DRX definition and also analysed the impact of DRX on RRM requirements. Following are the main proposals based on the analysis:

• Proposal 1 : Definition of the states when no DRX is used and when the DRX is used shall be defined in TS 38.133.

• Proposal 2: To enable time tracking in DRX the UE shall assume that TRS are available at the UE before the DRX ON provided that the SMTC periodicity > 80 ms and DRX cycle > 1280 ms.

• Proposal 3: The proposed requirements in terms of measurement time for RLM on NR PSCell, NR intra-frequency measurements and inter- frequency measurements are expressed in tables 2, 3 and 4 respectively.

Table 2: RLM Requirements for NR PSCell in DRX

Table 3: Measurement Requirements for NR Intra-frequency Measurements in DRX

Table 4: Measurement Requirements for NR Inter-frequency Measurements in DRX

[0136] A TP to TS 38.133 to define DRX active and inactive times is provided in R4-17xxx, TP to TS 38.133 v0.3.0: DRX definition, Ericsson.

Example Embodiments

[0137] Some example embodiments of the present disclosure are as follows. Group A Embodiments

[0138] Embodiment 1 : A method of operation of a wireless device in a wireless communication system, comprising: determining (800) a configuration of one or more reference signals to be used by the wireless device for one or more timing and/or frequency synchronization related procedures with respect to a cell, wherein determining the configuration of the one or more reference signals comprises determining the configuration of the one or more reference signals based on an activity level of the wireless device, a transmit timing accuracy requirement on the wireless device, a speed of the wireless device, and/or a bandwidth or Bandwidth Part, BWP, of the wireless device; and performing (802) the one or more timing and/or frequency synchronization related procedures with respect to the cell using the one or more reference signals in accordance with the determined configuration.

[0139] Embodiment 2: The method of embodiment 1 wherein the one or more reference signals comprise a Tracking Reference Signal, TRS, a synchronization signal, and/or a Demodulation Reference Signal, DMRS.

[0140] Embodiment 3: The method of embodiment 1 or 2 wherein the configuration of the one or more reference signals comprises: a periodicity of the one or more reference signals; a bandwidth of the one or more reference signals; a transmit power of the one or more reference signals; a transmit power boosting of the one or more reference signals with respect to a reference level or with respect to another signal; a density of the one or more reference signals in time and/or frequency; a number of symbols per slot; and/or a number of slots with the one or more reference signals.

[0141] Embodiment 4: The method of any one of embodiments 1 to 3 wherein the one or more timing and/or frequency related procedures comprise: automatic gain control, time tracking, and/or frequency tracking.

[0142] Embodiment 5: The method of any one of embodiments 1 to 4 wherein determining the configuration comprises determining the configuration further based on a message received from a network node and/or a predefined rule. [0143] Embodiment 6: The method of any one of embodiments 1 to 5 wherein determining the configuration comprises determining a value of a parameter T, wherein the wireless device is configured to receive the one or more reference signals within a time T prior to a beginning of wireless device activity of the wireless device.

[0144] Embodiment /: The method of embodiment 6 wherein the beginning of wireless device activity of the wireless device is a beginning of Discontinuous Reception, DRX, ON.

[0145] Embodiment 8: The method of any one of embodiments 1 to 7 wherein determining the configuration of the one or more reference signals comprises determining the configuration of the one or more reference signals based on the activity level of the wireless device.

[0146] Embodiment 9: The method of embodiment 8 wherein the activity level of the wireless device is a function of: a DRX configuration of the wireless device; an extended DRX, eDRX, configuration of the wireless device; a paging configuration of the wireless device; a Discontinuous Transmission, DTX, configuration of the wireless device; uplink transmissions of the wireless device; and/or a Radio Resource Control, RRC, state of the wireless device.

[0147] Embodiment 10: The method of embodiment 8 or 9 wherein

determining the configuration comprises: selecting a first configuration as the configuration of the one or more reference signals if the activity level of the wireless device is below a predefined or preconfigured threshold; and selecting a second configuration as the configuration of the one or more reference signals if the activity level of the wireless device is above a predefined or preconfigured threshold.

[0148] Embodiment 11 : The method of any one of embodiments 1 to 7 wherein determining the configuration of the one or more reference signals comprises determining the configuration of the one or more reference signals based on the transmit timing accuracy requirement on the wireless device.

[0149] Embodiment 12: The method of embodiment 11 wherein determining the configuration comprises: selecting a first configuration as the configuration of the one or more reference signals if the transmit timing accuracy requirement is less accurate than a predefined or preconfigured threshold; and selecting a second configuration as the configuration of the one or more reference signals if the transmit timing accuracy requirement is more accurate than a predefined or preconfigured threshold.

[0150] Embodiment 13: The method of any one of embodiments 1 to 7 wherein determining the configuration of the one or more reference signals comprises determining the configuration of the one or more reference signals based on the speed of the wireless device.

[0151] Embodiment 14: The method of embodiment 13 wherein determining the configuration comprises: selecting a first configuration as the configuration of the one or more reference signals if the speed of the wireless device is less than a predefined or preconfigured threshold; and selecting a second configuration as the configuration of the one or more reference signals if the speed of the wireless device is more than a predefined or preconfigured threshold.

[0152] Embodiment 15: The method of any one of embodiments 1 to 7 wherein determining the configuration of the one or more reference signals comprises determining the configuration of the one or more reference signals based on the bandwidth or BWP of the wireless device.

[0153] Embodiment 16: The method of embodiment 15 wherein determining the configuration comprises: selecting a first configuration as the configuration of the one or more reference signals if the bandwidth or BWP of the wireless device is less than a predefined or preconfigured threshold; and selecting a second configuration as the configuration of the one or more reference signals if the bandwidth or BWP of the wireless device is more than a predefined or preconfigured threshold.

[0154] Embodiment 17: The method of any of the previous embodiments, further comprising: providing user data; and forwarding the user data to a host computer via the transmission to the base station. Group B Embodiments

[0155] Embodiment 18: A method of operation of a network node in a wireless communication system, comprising: providing (900), to a wireless device, a configuration of one or more reference signals to be used by the wireless device for one or more timing and/or frequency synchronization related procedures with respect to a cell, wherein the configuration of the one or more reference signals is based on an activity level of the wireless device, a transmit timing accuracy requirement on the wireless device, a speed of the wireless device, and/or a bandwidth or Bandwidth Part, BWP, of the wireless device.

[0156] Embodiment 19: The method of embodiment 18 further comprising transmitting (902) the one or more reference signals in accordance with the determined configuration.

[0157] Embodiment 20: The method of embodiment 19 wherein the one or more reference signals comprise a Tracking Reference Signal, TRS, a

synchronization signal, and/or a Demodulation Reference Signal, DMRS.

[0158] Embodiment 21 : The method of embodiment 19 or 20 wherein the configuration of the one or more reference signals comprises: a periodicity of the one or more reference signals; a bandwidth of the one or more reference signals; a transmit power of the one or more reference signals; a transmit power boosting of the one or more reference signals with respect to a reference level or with respect to another signal; a density of the one or more reference signals in time and/or frequency; a number of symbols per slot; and/or a number of slots with the one or more reference signals.

[0159] Embodiment 22: The method of any one of embodiments 19 to 21 wherein the one or more timing and/or frequency related procedures comprise: automatic gain control, time tracking, and/or frequency tracking.

[0160] Embodiment 23: The method of any one of embodiments 19 to 22 wherein the configuration comprises a value of a parameter T, wherein the wireless device is configured to receive the one or more reference signals within a time T prior to a beginning of wireless device activity of the wireless device. [0161] Embodiment 24: The method of embodiment 23 wherein the beginning of wireless device activity of the wireless device is a beginning of Discontinuous Reception, DRX, ON.

[0162] Embodiment 25: The method of any one of embodiments 19 to 24 wherein the configuration of the one or more reference signals is based on the activity level of the wireless device.

[0163] Embodiment 26: The method of embodiment 25 wherein the activity level of the wireless device is a function of: a DRX configuration of the wireless device; an extended DRX, eDRX, configuration of the wireless device; a paging configuration of the wireless device; a Discontinuous Transmission, DTX, configuration of the wireless device; uplink transmissions of the wireless device; and/or a Radio Resource Control, RRC, state of the wireless device.

[0164] Embodiment 27: The method of embodiments 18 to 26 wherein the configuration comprises: a first configuration of the one or more reference signals if the activity level of the wireless device is below a predefined or preconfigured threshold; and a second configuration of the one or more reference signals if the activity level of the wireless device is above a predefined or preconfigured threshold.

[0165] Embodiment 28: The method of any one of embodiments 19 to 24 wherein the configuration of the one or more reference signals is based on the transmit timing accuracy requirement on the wireless device.

[0166] Embodiment 29: The method of embodiment 28 wherein the configuration comprises: a first configuration of the one or more reference signals if the transmit timing accuracy requirement is less accurate than a predefined or preconfigured threshold; and a second configuration of the one or more reference signals if the transmit timing accuracy requirement is more accurate than a predefined or preconfigured threshold.

[0167] Embodiment 30: The method of any one of embodiments 19 to 24 wherein the configuration of the one or more reference signals is based on the speed of the wireless device. [0168] Embodiment 31 : The method of embodiment 30 wherein the configuration comprises: a first configuration of the one or more reference signals if the speed of the wireless device is less than a predefined or preconfigured threshold; and a second configuration of the one or more reference signals if the speed of the wireless device is more than a predefined or preconfigured threshold.

[0169] Embodiment 32: The method of any one of embodiments 19 to 24 wherein the configuration of the one or more reference signals is based on the bandwidth or BWP of the wireless device.

[0170] Embodiment 33: The method of embodiment 32 wherein the configuration comprises: a first configuration of the one or more reference signals if the bandwidth or BWP of the wireless device is less than a predefined or preconfigured threshold; and a second configuration of the one or more reference signals if the bandwidth or BWP of the wireless device is more than a predefined or preconfigured threshold.

[0171] Embodiment 34: The method of any of the previous embodiments, further comprising: obtaining user data; and forwarding the user data to a host computer or a wireless device.

Group C Embodiments

[0172] Embodiment 35: A wireless device for operation in a wireless communication system, the wireless device comprising: at least one transmitter and at least one receiver; and processing circuitry configured to perform any of the steps of any of the Group A embodiments.

[0173] Embodiment 36: A network node for operation in a wireless

communication system, the network node comprising: at least one network interface and/or at least transmitter and/or at least one receiver; and processing circuitry configured to perform any of the steps of any of the Group B

embodiments.

[0174] Embodiment 37: A User Equipment (UE) for operation in a wireless communication system, the UE comprising: an antenna configured to send and receive wireless signals; radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry; the processing circuitry being

configured to perform any of the steps of any of the Group A embodiments; an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry; an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and a battery connected to the processing circuitry and configured to supply power to the UE.

[0175] Embodiment 38: A communication system including a host computer comprising: processing circuitry configured to provide user data; and a

communication interface configured to forward the user data to a cellular network for transmission to a User Equipment (UE); wherein the cellular network comprises a radio access node having a radio interface and processing circuitry, the radio access node’s processing circuitry configured to perform any of the steps of any of the Group B embodiments.

[0176] Embodiment 39: The communication system of the previous embodiment further including the radio access node.

[0177] Embodiment 40: The communication system of the previous 2 embodiments, further including the UE, wherein the UE is configured to communicate with the radio access node.

[0178] Embodiment 41 : The communication system of the previous 3 embodiments, wherein: the processing circuitry of the host computer is configured to execute a host application, thereby providing the user data; and the UE comprises processing circuitry configured to execute a client application associated with the host application.

[0179] Embodiment 42: A method implemented in a communication system including a host computer, a base station, and a User Equipment (UE), the method comprising: at the host computer, providing user data; and at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the radio access node, wherein the radio access node performs any of the steps of any of the Group B embodiments.

[0180] Embodiment 43: The method of the previous embodiment, further comprising, at the radio access node, transmitting the user data.

[0181] Embodiment 44: The method of the previous 2 embodiments, wherein the user data is provided at the host computer by executing a host application, the method further comprising, at the UE, executing a client application associated with the host application.

[0182] Embodiment 45: A User Equipment (UE) configured to communicate with a radio access node, the UE comprising a radio interface and processing circuitry configured to perform the method of the previous 3 embodiments.

[0183] Embodiment 46: A communication system including a host computer comprising: processing circuitry configured to provide user data; and a communication interface configured to forward user data to a cellular network for transmission to a User Equipment (UE); wherein the UE comprises a radio interface and processing circuitry, the UE’s components configured to perform any of the steps of any of the Group A embodiments.

[0184] Embodiment 47: The communication system of the previous embodiment, wherein the cellular network further includes a radio access node configured to communicate with the UE.

[0185] Embodiment 48: The communication system of the previous 2 embodiments, wherein: the processing circuitry of the host computer is configured to execute a host application, thereby providing the user data; and the UE’s processing circuitry is configured to execute a client application associated with the host application.

[0186] Embodiment 49: A method implemented in a communication system including a host computer, a radio access node and a User Equipment (UE), the method comprising: at the host computer, providing user data; and at the host computer, initiating a transmission carrying the user data to the UE via a cellular network comprising the radio access node, wherein the UE performs any of the steps of any of the Group A embodiments. [0187] Embodiment 50: The method of the previous embodiment, further comprising at the UE, receiving the user data from the radio access node.

[0188] Embodiment 51 : A communication system including a host computer comprising: communication interface configured to receive user data originating from a transmission from a User Equipment (UE) to a radio access node;

wherein the UE comprises a radio interface and processing circuitry, the UE’s processing circuitry configured to perform any of the steps of any of the Group A embodiments.

[0189] Embodiment 52: The communication system of the previous embodiment, further including the UE.

[0190] Embodiment 53: The communication system of the previous 2 embodiments, further including the radio access node, wherein the radio access node comprises a radio interface configured to communicate with the UE and a communication interface configured to forward to the host computer the user data carried by a transmission from the UE to the radio access node.

[0191] Embodiment 54: The communication system of the previous 3 embodiments, wherein: the processing circuitry of the host computer is configured to execute a host application; and the UE’s processing circuitry is configured to execute a client application associated with the host application, thereby providing the user data.

[0192] Embodiment 55: The communication system of the previous 4 embodiments, wherein: the processing circuitry of the host computer is configured to execute a host application, thereby providing request data; and the UE’s processing circuitry is configured to execute a client application associated with the host application, thereby providing the user data in response to the request data.

[0193] Embodiment 56: A method implemented in a communication system including a host computer, a radio access node and a User Equipment (UE), the method comprising: at the host computer, receiving user data transmitted to the radio access node from the UE, wherein the UE performs any of the steps of any of the Group A embodiments. [0194] Embodiment 57: The method of the previous embodiment, further comprising, at the UE, providing the user data to the radio access node.

[0195] Embodiment 58: The method of the previous 2 embodiments, further comprising: at the UE, executing a client application, thereby providing the user data to be transmitted; and at the host computer, executing a host application associated with the client application.

[0196] Embodiment 59: The method of the previous 3 embodiments, further comprising: at the UE, executing a client application; and at the UE, receiving input data to the client application, the input data being provided at the host computer by executing a host application associated with the client application; wherein the user data to be transmitted is provided by the client application in response to the input data.

[0197] Embodiment 60: A communication system including a host computer comprising a communication interface configured to receive user data originating from a transmission from a User Equipment (UE) to a radio access node, wherein the radio access node comprises a radio interface and processing circuitry, the radio access node’s processing circuitry configured to perform any of the steps of any of the Group B embodiments.

[0198] Embodiment 61 : The communication system of the previous embodiment further including the radio access node.

[0199] Embodiment 62: The communication system of the previous 2 embodiments, further including the UE, wherein the UE is configured to communicate with the radio access node.

[0200] Embodiment 63: The communication system of the previous 3 embodiments, wherein: the processing circuitry of the host computer is configured to execute a host application; and the UE is configured to execute a client application associated with the host application, thereby providing the user data to be received by the host computer.

[0201] Embodiment 64: A method implemented in a communication system including a host computer, a base station, and a User Equipment (UE), the method comprising: at the host computer, receiving, from the radio access node, user data originating from a transmission which the radio access node has received from the UE, wherein the UE performs any of the steps of any of the Group A embodiments.

[0202] Embodiment 65: The method of the previous embodiment, further comprising at the radio access node, receiving the user data from the UE.

[0203] Embodiment 66: The method of the previous 2 embodiments, further comprising at the radio access node, initiating a transmission of the received user data to the host computer.

[0204] At least some of the following abbreviations may be used in this disclosure. If there is an inconsistency between abbreviations, preference should be given to how it is used above. If listed multiple times below, the first listing should be preferred over any subsequent listing(s).

ps Microsecond

3GPP Third Generation Partnership Project

5G Fifth Generation

AGC Automatic Gain Control

AP Access Point

ASIC Application Specific Integrated Circuit

ATFRS Automatic Gain Control, Time, and Frequency

Tracking Reference Signal

BS Base Station

BW Bandwidth

BWP Bandwidth Part

CP Cyclic Prefix

CPE Customer Premise Equipment

CPU Central Processing Unit

CSI-RS Channel State Information Reference Signal

D2D Device-to-Device

DMRS Demodulation Reference Signal • DRX Discontinuous Reception

• DSP Digital Signal Processor

• DTX Discontinuous Transmission

• eDRX Extended Discontinuous Reception

• eNB Enhanced or Evolved Node B

• FFS For Further Study

• FPGA Field Programmable Gate Array

• GHz Gigahertz

. gNB New Radio Node B

• HST High Speed Train

• Hz Flertz

• kHz Kilohertz

• km Kilometer

• LEE Laptop Embedded Equipment

• LME Laptop Mounted Equipment

• LTE Long Term Evolution

• M2M Machine-to-Machine

• MCE Multi-Cell/Multicast Coordination Entity

• MDT Minimization of Drive Tests

• MIMO Multiple Input Multiple Output

• MME Mobility Management Entity

• ms Millisecond

• MSR Multi-Standard Radio

• NG Next Generation

• ng-eNB Next Generation Enhanced or Evolved Node B

• NR New Radio

• ns Nanosecond

• OFDM Orthogonal Frequency Division Multiplexing

• OTT Over-the-Top

• PBCH Physical Broadcast Channel • PCell Primary Cell

• PDCCH Physical Downlink Control Channel

• PDSCH Physical Downlink Shared Channel

• PRACH Physical Random Access Channel

• PSCell Primary Secondary Cell

• PSS Primary Synchronization Signal

• PUCCH Physical Uplink Control Channel

• PUSCH Physical Uplink Shared Channel

• RACH Random Access Channel

• RAM Random Access Memory

• RAN Radio Access Network

• RAT Radio Access Technology

• RB Resource Block

• ROM Read Only Memory

• RRC Radio Resource Control

• RRH Remote Radio Head

• RRU Remote Radio Unit

• SCell Secondary Cell

• SCS Subcarrier Spacing

• SON Self-Organizing Network

• SRS Sounding Reference Signal

• SS Synchronization Signal

• SSB Synchronization Signal Block

• SSS Secondary Synchronization Signal

• TRP Transmission/Reception Point

• TRS Tracking Reference Signal

• TS Technical Specification

• UE User Equipment

• USB Universal Serial Bus

• WB Wideband [0205] Those skilled in the art will recognize improvements and modifications to the embodiments of the present disclosure. All such improvements and modifications are considered within the scope of the concepts disclosed herein.