Description

The present invention relates to the field of mobile communication systems or networks, more specifically to approaches for monitoring the performance of configured-grant, CG, transmissions in mobile communication systems or networks.

Fig. 1 is a schematic representation of an example of a terrestrial wireless network 100 including, as is shown in Fig. 1 (a), a core network 102 and one or more radio access networks RANi, RAN ₂ , ... RANN. Fig. 1 (b) is a schematic representation of an example of a radio access network RAN _n that may include one or more base stations gNBi to gNBs, each serving a specific area surrounding the base station schematically represented by respective cells IO6 ₁ to 106s. The base stations are provided to serve users within a cell. The term base station, BS, refers to a gNB in 5G networks, an eNB in UMTS/LTE/LTE-A/ LTE-A Pro, or just a BS in other mobile communication standards. A user may be a stationary device or a mobile device. The wireless communication system may also be accessed by mobile or stationary loT devices which connect to a base station or to a user. The mobile devices or the loT devices may include physical devices, ground based vehicles, such as robots or cars, aerial vehicles, such as manned or unmanned aerial vehicles (UAVs), the latter also referred to as drones, buildings and other items or devices having embedded therein electronics, software, sensors, actuators, or the like as well as network connectivity that enables these devices to collect and exchange data across an existing network infrastructure. Fig. 1(b) shows an exemplary view of five cells, however, the RANn may include more or less such cells, and RAN _n may also include only one base station. Fig. 1(b) shows two users UEi and UE2, also referred to as user equipment, UE, that are in cell 106 ₂ and that are served by base station gNB2. Another user UE ₃ is shown in cell 106 ₄ which is served by base station gNB . The arrows IO8 ₁ , 108 ₂ and 108 ₃ schematically represent uplink/downlink connections for transmitting data from a user UEi, UE2 and UE3 to the base stations gNB ₂ , gNB ₄ or for transmitting data from the base stations gNB ₂ , gNB ₄ to the users UEi, UE2, UE3. Further, Fig. 1 (b) shows two loT devices 110i and 11O2 in cell I O64, which may be stationary or mobile devices. The loT device 110i accesses the wireless communication system via the base station gNB ₄ to receive and transmit data as schematically represented by arrow 112i. The loT device 110 ₂ accesses the wireless communication system via the user UE3 as is schematically represented by arrow 1 122. The respective base station gNBi to gNBs may be connected to the core network 102, e.g. via the S1 interface, via respective backhaul links 1 14i to 114s, which are schematically represented in Fig. 1 (b) by the arrows pointing to“core”. The core network 102 may be connected to one or more external networks. Further, some of all of the respective base station gNBt to gNBs may connected, e.g. via the S1 or X2 interface or the XN interface in NR, with each other via respective backhaul links 116i to 1 165, which are schematically represented in Fig. 1 (b) by the arrows pointing to“gNBs".

For data transmission a physical resource grid may be used. The physical resource grid may comprise a set of resource elements to which various physical channels and physical signals are mapped. For example, the physical channels may include the physical downlink, uplink and sidelink shared channels (PDSCH, PUSCH, PSSCH) carrying user specific data, also referred to as downlink, uplink and sidelink payload data, the physical broadcast channel (PBCH) carrying for example a master information block (MIB) and a system information block (SIB), the physical downlink, uplink and sidelink control channels (PDCCH, PUCCH, PSSCH) carrying for example the downlink control information (DCI), the uplink control information (UCI) and the sidelink control information (SCI). For the uplink, the physical channels may further include the physical random access channel (PRACH or RACH) used by UEs for accessing the network once a UE synchronized and obtained the MIB and SIB. The physical signals may comprise reference signals or symbols (RS), synchronization signals and the like. The resource grid may comprise a frame or radio frame having a certain duration in the time domain and having a given bandwidth in the frequency domain. The frame may have a certain number of subframes of a predefined length, e.g. 1 ms. Each subframe may include one or more slots of 12 or 14 OFDM symbols depending on the cyclic prefix (CP) length. A frame may also consist of a smaller number of OFDM symbols, e.g. when utilizing shortened transmission time intervals (sTTI) or a mini-slot/non- slot-based frame structure comprising just a few OFDM symbols.

The wireless communication system may be any single-tone or multicarrier system using frequency-division multiplexing, like the orthogonal frequency-division multiplexing (OFDM) system, the orthogonal frequency-division multiple access (OFDMA) system, or any other IFFT-based signal with or without CP, e.g. DFT-s-OFDM. Other waveforms, like non- orthogonal waveforms for multiple access, e.g. filter-bank multicarrier (FBMC), generalized frequency division multiplexing (GFDM) or universal filtered multi carrier (UFMC), may be used. The wireless communication system may operate, e.g., in accordance with the LTE- Advanced pro standard or the 5G or NR, New Radio, standard.

The wireless network or communication system depicted in Fig. 1 may by a heterogeneous network having distinct overlaid networks, e.g., a network of macro cells with each macro cell including a macro base station, like base station gNBi to gNBs, and a network of small cell base stations (not shown in Fig. 1), like femto or pico base stations.

In addition to the above described terrestrial wireless network also non-terrestrial wireless communication networks exist including spaceborne transceivers, like satellites, and/or airborne transceivers, like unmanned aircraft systems. The non-terrestrial wireless communication network or system may operate in a similar way as the terrestrial system described above with reference to Fig. 1 , for example in accordance with the LTE-Advanced Pro standard or the 5G or NR, new radio, standard.

In mobile communication networks, for example in a network like that described above with reference to Fig. 1 , like an LTE or 5G/NR network, there may be UEs that communicate directly with each other over one or more sidelink (SL) channels, e.g., using the PCS interface. UEs that communicate directly with each other over the sidelink may include vehicles communicating directly with other vehicles (V2V communication), vehicles communicating with other entities of the wireless communication network (V2X communication), for example roadside entities, like traffic lights, traffic signs, or pedestrians. Other UEs may not be vehicular related UEs and may comprise any of the above-mentioned devices. Such devices may also communicate directly with each other (D2D communication) using the SL channels.

When considering two UEs directly communicating with each other over the sidelink, both UEs may be served by the same base station so that the base station may provide sidelink resource allocation configuration or assistance for the UEs. For example, both UEs may be within the coverage area of a base station, like one of the base stations depicted in Fig. 1. This is referred to as an“in-coverage” scenario. Another scenario is referred to as an“out- of-coverage” scenario. It is noted that“out-of-coverage” does not mean that the two UEs are not within one of the cells depicted in Fig. 1 , rather, it means that these UEs

may not be connected to a base station, for example, they are not in an RRC connected state, so that the UEs do not receive from the base station any sidelink resource allocation configuration or assistance, and/or may be connected to the base station, but, for one or more reasons, the base station may not provide sidelink resource allocation configuration or assistance for the UEs, and/or

may be connected to the base station that may not support NR V2X services, e.g. GSM, UMTS, LTE base stations.

When considering two UEs directly communicating with each other over the sidelink, e.g. using the PC5 interface, one of the UEs may also be connected with a BS, and may relay information from the BS to the other UE via the sidelink interface. The relaying may be performed in the same frequency band (in-band-relay) or another frequency band (out-of- band relay) may be used. In the first case, communication on the Uu and on the sidelink may be decoupled using different time slots as in time division duplex, TDD, systems.

In a wireless communication system, e.g., the one described above with reference to Fig. 1 , configured grant, CG, transmissions may be implemented as described, e.g., in reference [1], which allow a low latency communication by authorizing a user equipment, UE, to transmit a message without a scheduling grant for this message. Fig. 2 schematically illustrates the concept of CG transmissions in a mobile communication network, for example a NR or 5G network. Fig. 2 illustrates schematically a single cell, for example, a cell as depicted above in Fig. 1 , including the base station gNB as well as two mobile devices UE1 , UE2, for example vehicles or the like. The base station gNB allocates time-frequency resources on which a CG transmission is to be performed. Fig. 2 illustrates the time- frequency resources 200 that are provided or allocated by the gNB for CG transmissions, for example, with a certain periodicity. The configured grant resources 200 may be randomly utilized by the user as UE1 , UE2 when they have data to transmit. By assigning the configured grant resources, the system or network eliminates the packet transmission delay for a scheduling request procedure and increases the utilization ratio of the allocated radio resources. In the example of Fig. 2, the user UE1 has data 202i to be transmitted. The data 202i may be available or generated at a time t1 , and at a time t ₂ the data 202i may be transmitted by the user UE1 using the configured grant resources without the need for a scheduling request procedure. Further data 202 ₂ may be available at time t3, and the data may be transmitted using the configured grant resources at time t4. At the other user, UE2, data 2023 may be available at a time t5 which is then transmitted using the CG resources at time t6. The time-frequency resources, also referred to as the CG resources or the CG resource pool, on which the CG transmission is transmitted may be preconfigured, for example via radio resource control, RRC, signaling alone, also referred to as a CG type 1 , or via RRC signaling and downlink L1/L2 signaling, also referred to as CG type 2 (see references [1] and [2]). CG transmissions as explained above with reference to Fig. 2 may be used for low latency applications, for example for an ultra-reliable low-latency communication, URLLC, for vehicle-to-everything, V2X, scenarios or applications or device- to-device, D2D, scenarios or applications.

It is noted that the information in the above section only for enhancing the understanding of the background of the invention and therefore it may contain information that does not form prior art that is already known to a person skilled in the art.

Starting from a prior art as described above, there may be a need for improvements in the wireless communication among entities of a wireless communication system using configured grant, CG, transmissions.

Embodiments of the present invention are now described in further detail with reference to the accompanying drawings:

Fig. 1 shows a schematic representation of an example of a wireless communication system;

Fig. 2 schematically illustrates the concept of CG transmissions in a mobile communication network;

Fig. 3 illustrates examples indicating misdetections/false alarms versus SNR when detecting at a gNB signals from a first user under the assumption that two users transmit over the same CG resources;

Fig. 4 is a schematic representation of a wireless communication system including a transmitter, like a base station, and one or more receivers, like user devices, UEs;

Fig. 5 illustrates an embodiment for providing a counter-triggered UE report;

Fig. 6 illustrates an embodiment of using periodic/timer-based UE reports; Fig. 7 illustrates an embodiment of a gNB-triggered UE report for S prior CG instances so that the feedback or report provides activity information for the S CG instances before or prior to the gNB request;

Fig. 8 illustrates an embodiment of using a gNB-triggered UE report for S future CG instances so that the activity information is provided for the S CG instances following the gNB request; Fig. 9 illustrates the use of sequence-numbered messages in accordance with embodiments; and

Fig. 10 illustrates an example of a computer system on which units or modules as well as the steps of the methods described in accordance with the inventive approach may execute.

Embodiments of the present invention are now described in more detail with reference to the accompanying drawings in which the same or similar elements have the same reference signs assigned.

As described above, in wireless communication systems or networks, like those described with reference to Fig. 1 and to Fig. 2, the respective entities may communicate using CG transmissions. For every connected UE with enabled CG capability, a NR base station, gNB, is aware of the time-frequency resources or positions which are configured for the CG transmissions of the UE. More specifically, the gNB is aware of the time-frequency resources for the CG transmissions and that may be used by one or more of the UEs being in coverage with the gNB. The UEs may randomly use the CG time-frequency resources for a transmission to the gNB so that there may also be situations in which a collision occurs, namely when two or more UEs use the same resources at a certain time for the CG transmission.

The gNB determines for a certain CG transmission instance whether that CG instance carries a message from the UE or not. The certain CG transmission instance may be a certain number of time-frequency resources allocated for the CG transmissions, like the CG resources 200 indicated in Fig. 2. As is also shown in Fig. 2, not each of the CG resources may be used by the UEs for the CG transmission. In other words, in case a UE does not have a message to be transmitted on a CG transmission resource, for example a message delivered from upper layers, the UE does not transmit on these resources (see reference [1]). Therefore, the gNB needs to determine whether a CG instance is a used instance, i.e., an instance carrying a message from the UE, or whether the CG instance is a unused instance not carrying a message from the UE.

In accordance with a first approach, referred to herein as an Always Decode approach, for determining whether a CG instance carries a message from the UE or not, the gNB attempts to decode every CG instance. In case there is no transmission on the CG resources at this instance, the gNB determines a decode failure. This approach may involve a high amount of decode operations which are computationally expensive. A second approach, referred to herein as Detect and Decode approach, for determining whether a CG instance carries a message from the UE or not, the gNB employs a detector so as to determine for every CG instance whether the CG instance contains a signal from the UE. In case the detector decides that a signal from the UE is present, decoding is attempted by the gNB. For example, a decoder may exploit the demodulation reference signals, DMRSs, as provided by the UE in the transmission in its decision making (see reference [3]).

The reception of CG transmissions from the UE at the gNB may be associated with a message error rate, MER, a false alarm rate, and a misdetection rate. These rates may be defined as follows:

Message error rate, MER: In case the information bits transmitted by a UE in a CG instance are not received correctly at the gNB, a message error occurs. The ratio of a number of message errors to a number of used CG instances, i.e., the number of CG instances carrying a message from a UE, is defined as the MER.

False alarm rate: The false alarm rate is a property of the detector used at the gNB for detecting signals from the UE. A false alarm event occurs when a UE does not transmit on a CG instance, i.e., there is no signal from the UE, but the detector at the gNB decides that there was a transmission by the UE. The false alarm rate may be defined as the ratio of a number of false alarm events to a number of unused CG instances, i.e., CG instances not carrying a message from the UE.

Misdetection rate: This is a property of the detector at the gNB. A misdetection event occurs when a UE transmits on a CG instance, i.e., there is a signal from the UE, but the detector at the gNB decides that there was no transmission by the UE. The misdetection rate may be defined as the ratio of a number of misdetection events to a number of used CG instances.

In the Always Decode approach, the gNB may not determine whether a decode failure is caused by an unused CG instance or by a disturbed transmission, for example a disturbed transmission due to noise and/or interference, in a used CG instance. As a consequence, the gNB may not estimate the MER of the CG transmissions. Without an estimation of the MER, the gNB may not be confident that the CG transmissions deliver the expected performance. Moreover, such a situation prevents the gNB from applying corrective actions, for example, adapting a threshold used in the detector in the detect and decode approach or the like.

When considering the detect and decode approach, the MER may be influenced by the misdetection rate of the detector and the block error rate, BLER of the transmission scheme. A misdetection may occur when the detector fails to detect a desired signal, e.g., due to a low SINR. The BLER target may be less than 10 ⁴ for URLLC or V2X scenarios. The misdetection rate may be chosen to be significantly lower than the BLER, more specifically in such a way that the MER is approximately equal to the BLER. The desired misdetection rate may be selected by fixing the false alarm rate of the detector at the gNB. Typical values of the desired false alarm rate may have a range of 10 ² to 10 ^‘3 . For a detection algorithm, the detection threshold may be calculated assuming a certain model, for example assuming a certain coherence bandwidth, a certain number of users and a certain number of frequency errors and the like. In case there is a mismatch between the assumed signal model and the reality, the achieved false alarm or misdetection rates deviate from the target value.

This may be significant in situations with a high signal-to-noise ratio, SNR, and a low signal- to-interference ratio, SIR, as it may occur when multiple UEs transmit over the same CG resources.

Thus, for CG transmissions the situation is different from conventional uplink data transmissions using scheduling requests. In uplink data transmissions, a data transmission is initiated by a scheduling request and maintained by the buffer status reports. The gNB allocates the UE uplink resources where to transmit the data. Therefore, there is no situation in which the gNB attempts to decode when there is actually no signal transmitted as then also no uplink resources are scheduled for the UE. Consequently, the gNB may directly detect a decode success or a decode failure, and the decoding status may be used in HARQ so as to further improve the reliability of the transmission. Compared to conventional uplink data transmissions, CG transmissions are different and are mainly intended to deliver short messages with the low latency. The latency is reduced by leaving out the scheduling request and the scheduling grant. The UE is allowed to immediately transmit on the preconfigured CG resources when a message is ready and since the latency requirement is an issue, retransmission mechanisms, like HARQ, may not be employed. Instead, a preconfigured number of repetitions may be sent without any feedback.

At the gNB a decoder may be employed implementing a certain detection algorithm for detecting signals from a receiver over a wireless communication channel. The detection algorithm may be based on a certain model. However, deviations from a detector operating point may occur, for example due to parameter estimation errors or a mismatch of the model used for selecting the detector operation point. Such deviations are discussed, for example, in reference [6] For a given model, a designer may attempt to provide a constant false alarm rate detector which is immune to parameter estimation errors, however, this requires to choose a model, which, usually, is selected so as to be sufficiently accurate in the expected deployment scenarios so that any deviation in the false alarm rate due to modeling errors is negligible. In typical detection algorithms, false alarm rate deviations tend to increase at higher SNRs where the modeling error has a significant influence on the statistics of the detection metric.

When considering CG transmissions, a detection algorithm for detecting signals from a receiver over a wireless communication channel may be based on a certain model. The model is based on certain error rates, however, such error rates may experience deviations. A polynomial modeling of channel variations in the frequency direction can be considered as a suitable model in constructing a detector. A designer may also adopt a different type of modeling instead of the polynomial model. However, the issue of modeling error is expected in all cases and therefore, for the following the issues are discussed with respect to the polynomial model. The amount of deviation from reality may depend on the degree polynomial modeling of channel variations used. The deviation may be low in case a high degree polynomial modeling of channel variations is applied, and may be high in case a low degree of polynomial modeling of channel variations is applied.

Fig. 3 illustrates examples indicating misdetections/false alarms versus SNR when detecting at a gNB signals from a first user under the assumption that two users transmit over the same CG resources. Fig. 3 illustrates misdetection and false alarm curves obtained by the simulations assuming different degrees of polynomial modeling of channel variations. The subcarrier spacing is 30 kHz and the signal is transmitted over a contiguous set of 12 resource blocks. The first OFDM symbol of the transmission contains the DMRS symbols which are present in every alternate subcarrier. The model splits the signal bandwidth into multiple sections and a polynomial fit is assumed for the channel variations across the frequency direction in each section. The curves 1 a, 1 b illustrate the misdetection and false alarm curves for a polynomial modeling with a 0 ^th order (Nd=0) polynomial fit and 6 sections. The curves 2a, 2b illustrate the misdetection and false alarm curves for a polynomial modeling with a 1 ^st order (Nd=1 ) polynomial fit and 6 sections. The curves 3a, 3b illustrate the misdetection and false alarm curves for a polynomial modeling with a 2 ^nd order (Nd=2) polynomial fit and 6 sections. The curves 4a, 4b illustrate the misdetection and false alarm curves for a polynomial modeling with a 3 ^rd order (Nd-3) polynomial fit and 6 sections. The curves 5a, 5b illustrate the misdetection and false alarm curves for a polynomial modeling with a 4 ^th order (Nd=4) polynomial fit and 6 sections. The curves 6a, 6b illustrate the misdetection and false alarm curves for a polynomial modeling with a 5 ^th order (Nd=5) polynomial fit and 3 sections.

Fig. 3(a) illustrates the waveforms have by a simulation assuming a delay spread of 300 ns, a signal bandwidth, 12 RBs, split into sections of 6 or 3 sections, two users, a SIR of 0 dB and different degrees Nd of polynomial modeling channel variations in frequency in a section. The respective waveforms indicate the modeling errors, i.e., the deviations from the preferred ranges for the false alarm rate, which is set to 10 ³ , in the simulation. The respective curves illustrated in Fig. 3(a) show that the misdetection targets are achieved as all curves 1 a to 6a associated with the misdetection rate fall steeply at a SNR greater than 0 dB so as to be clearly in the range of the desired target which is at or below 10 ⁴ . On the other hand, one can see that the false alarm curves 1 b to 6b are within the desired range of 10 ² to 10 ³ for a SNR up to about 5 dB. However, for higher SNRs the respective false alarm targets deviate from the desired target. For example, at SNRs above 15 dB almost all false alarm curves 1 b to 6b are above the desired target range of 10 ² to 10 ³ . At the lower SNR values the modeling error is small and the noise is more significant, while at higher SNR values the noise is less significant and the modeling error becomes more prominent. Thus, in Fig. 3(a) while the misdetection target may be met, the false alarm rate attains a high value, i.e., the number of false alarm events increases. Fig. 3(b) illustrates similar results for a simulation assuming basically the same parameters as in Fig. 3(a) except that the delay spread is selected to be 100 ns so that the channel assumed for the simulation in Fig. 3(b) is considered to vary less than the channel used for the simulation in Fig. 3(a). Again, it can be seen that the misdetection targets for the different models 1 to 6 associated with respective misdetection curves 1 a to 6a are at or below the desired target of 10 ⁴ for SNRs greater than 0 dB while, in a similar way as in Fig. 3(a), the false alarm curves 1 b to 6b are within the target rage 10 ² to 10 ³ for a larger SNR range and, actually, in the depicted example only for models 1 and 2 the false alarm rate increases above the desired range for SNRs greater than 20 dB.

Fig. 3(c) and Fig. 3(d) illustrate further simulations using the same parameters as described above with reference to Fig. 3(a) and Fig. 3(b), respectively, however, the DMRS sequences used by the gNB for detecting signals from a user are orthogonal for the two users. In such situations, it can be seen from Fig. 3(c) and Fig. 3(d) that the false alarm curves 1 b to 6b are all at or below the target range of 10 ² to 10 ^-3 , however, the misdetection curves 1a to 6a may reach the desired target value of 10 ⁴ of below only at SNRs above 5 dB. The main observation is that the false alarm rate has deviates significantly from the targeted value of 10 ³ in the simulation.

The above-summarized simulation scenarios show that the gNB may not be in a position to determine whether a decode failure is caused by a false alarm or by a failure to decode a signal transmitted by the UE in a CG instance, i.e., the reliability of the CG transmissions may not be assessed by the gNB so that, like in the above-described Always Decode approach, the gNB is not in a position to make corrective actions so as to ensure that both the misdetection rate and the false alarm rate is within the desired target range.

The present invention provides improvements or enhancements in the wireless communication among entities of a wireless communication system using CG transmissions. Embodiments of the present invention provide approaches for addressing or recognizing deviations of respective error rates at certain SNRs so as to allow for countermeasures for ensuring a reliable transmission of CG messages. Further embodiments provide mechanisms allowing a receiver of CG transmissions to learn about deviations in the false alarm rate and/or the message error rates from a desired range so as to allow the receiver to apply corrective actions. Embodiments of the present invention are advantageous as they allow the gNB (for the uplink) or the UE (for the downlink) or the receiving UE (for a sidelink) to monitor the reliability of the CG transmissions received. Embodiments of the present invention are further advantageous as they allow the gNB (for the uplink), the UE (for the downlink) or the receiving UE (for the sidelink) to identify catastrophic situations, for example, in case the false alarm rate is very high the network may assume that one or more entities or devices are not operating properly or are defect. Yet further advantages of the embodiments of the present invention are that the gNB (for the uplink), the UE (for the downlink) or the receiving UE (for the sidelink) may reduce the false alarm rates if they are too high thereby reducing the number of unnecessary decoding operations. Embodiments provide the above improvements especially for situations in which more than one entity is allowed to transmit on the same CG resources.

Embodiments of the present invention may be implemented in a wireless communication system as depicted in Fig. 1 including base stations and users, like mobile terminals or loT devices. Fig. 4 is a schematic representation of a wireless communication system including a base station 300, and one or more UEs 302i to 302 _n . The base station 300 and the UEs 302 may communicate via one or more wireless communication links or channels 304a, 304b, 304c, like a radio link. The base station 300 may include one or more antennas ANT _T or an antenna array having a plurality of antenna elements, a signal processor 300a and a transceiver 300b, coupled with each other. The UEs 302 include one or more antennas ANTR or an antenna array having a plurality of antennas, a signal processor 302ai, 302a _n , and a transceiver 302bi, 302b _n coupled with each other. The base station 300 and the UEs 302 may communicate via respective first wireless communication links 304a and 304b, like a radio link using the Uu interface, while the UEs 302 may communicate with each other via a second wireless communication link 304c, like a radio link using the PCS interface. When the UEs are not served by the base station, are not be connected to a base station, for example, they are not in an RRC connected state, or, more generally, when no SL resource allocation configuration or assistance is provided by a base station, the UEs may communicate with each other over the sidelink. The system, the one or more UEs 302 and the base stations 300 may operate in accordance with the inventive teachings described herein.

ENTITY PERFORMING THE CG TRANSMISSION

The present invention provides (see for example claim 1) an apparatus for a communication with a receiver in a wireless communication system, wherein the apparatus is to transmit one or more configured grant, CG, messages to at least one receiver using one or more CG transmissions, and transmit feedback related to the one or more CG transmissions to the receiver.

In accordance with embodiments (see for example claim 2), the feedback related to the one or more CG transmissions includes one or more of:

• information associated with at least a number of CG transmissions performed by the apparatus during a certain time or period,

• an activity pattern report, the activity pattern report indicating a number of CG transmissions and a usage status of each CG instance in a certain period, the usage status indicating the actual resources on which the CG transmissions occurred.

In accordance with embodiments (see for example claim 3), the apparatus is to transmit a feedback message each time a predefined number (N) of CG transmissions has been transmitted, wherein the apparatus may transmit the feedback message in a control channel or in a data channel between the apparatus and the receiver, like the PDCCH, the PDSCH, the PUCCH, the PUSCH, the PSCCH or the PSSCH.

In accordance with embodiments (see for example claim 4), for transmitting the feedback related to the CG transmissions to the receiver, the apparatus is to add a flag, e.g., a one- bit flag, to a header of a predefined number (Q) of CG transmissions, and to

• set the flag to a first value in all but the last of the CG transmissions, and set the flag to a second value in the last CG transmission so as to indicate to the receiver that the predefined number (Q) of CG messages have been transmitted since the last time a CG message was transmitted with the flag set to the second value, or

• change a value of the flag each time the predefined number (Q) of CG transmissions has been transmitted so as to indicate that the predefined number (Q) of CG messages have been transmitted since a last change of the value of the flag.

In accordance with embodiments (see for example claim 5), the apparatus is to encode the flag as a modification of a subset of cyclic redundancy check, CRC, bits.

In accordance with embodiments (see for example claim 6), the apparatus is to transmit a feedback message in every predefined number (T) of CG transmission instances, wherein the feedback message contains a number of CG instances carrying a CG message from the apparatus in the predefined number (T) of CG transmission instances.

In accordance with embodiments (see for example claim 7), the apparatus is to send, responsive to a request from the receiver,

• a report containing a number of CG instances carrying a CG message from the apparatus in a predefined number (S) of past CG transmission instances, or

• a report containing a number of CG instances carrying a CG message from the apparatus in a predefined number (S) of future CG transmission instances.

In accordance with embodiments (see for example claim 8), the apparatus is to transmit the feedback message in a control channel or in a data channel between the apparatus and the receiver, like the PDCCH, the PDSCH, the PUCCH, the PUSCH, the PSCCH or the PSSCH.

In accordance with embodiments (see for example claim 9), the one or more CG messages are numbered so that a CG message has associated therewith a certain sequence number, and wherein the apparatus is to transmit to the receiver a CG message together with its associated sequence number.

In accordance with embodiments (see for example claim 10) the apparatus is to

• add to a CG message a sequence number represented by a predefined number (M) of bits, or

• encode the sequence number into the CG message, e.g., as a modification of a subset of cyclic redundancy check, CRC, bits.

In accordance with embodiments (see for example claim 1 1 ), the apparatus is to transmit an activity pattern report providing the CG activity information over a predefined number (R) of transmitted CG transmissions.

In accordance with embodiments (see for example claim 12), the apparatus is to transmit the activity pattern report

• responsive to a request from the receiver, or

• responsive to a timer reaching a certain value, or

• responsive to a counter reaching a certain value, the counter indicating a number of CG instances carrying a CG message from the apparatus. In accordance with embodiments (see for example claim 13), the report comprises a message including the predefined number (R) of bits, wherein each bit position uniquely identifies a CG instance in the predefined number (R) of past CG transmissions, and a value of a bit indicates whether the corresponding CG instance was carrying a CG message from the apparatus or not.

In accordance with embodiments (see for example claim 14), the apparatus is to receive from the receiver an acknowledgement of the reception of the feedback message.

In accordance with embodiments (see for example claim 15) , the apparatus is to

• receive a plurality of different CG configurations defining different sets of CG resources in the time-frequency plane, like different subframes; available for CG transmissions, like RRC messages, Layer1/Layer2 messages or a broadcast message, and

• transmit a distinct feedback for each of the CG configurations, or a combined feedback for the plurality of the CG configurations.

In accordance with embodiments (see for example claim 16),

• in case of a combined feedback and configurations causing the apparatus to transmit after every N CG transmissions a feedback message, the apparatus is to provide individual counters for each CG configuration and send the feedback when a sum of the individual counters equals a positive integer multiple of N, or

• in case of a combined feedback and configurations causing the apparatus to set a flag in Q CG transmissions, the apparatus is to provide individual counters for each CG configuration and set the flag when the sum of the individual counters equals a positive integer multiple of Q, or

• in case of a combined feedback and configurations causing the apparatus to transmit a feedback message containing a number of CG instances carrying a CG message from the apparatus in the last T, last S or next S CG transmissions, the apparatus is to provide individual counters for each CG configuration and include into the feedback a value equal to the sum of the counters,

• in case of a combined feedback and configurations causing the apparatus to add to a CG message a M-bit number indicating the sequence number, the apparatus is to provide a single counter for M for calculating the sequence numbers of CG messages of the different CG configurations, the counter being incremented whenever a CG message is transmitted in any of the CG configurations, or • in case of a combined feedback and configurations causing the apparatus to transmit to the receiver an activity pattern report providing the CG activity information over the latest R CG transmissions, the apparatus is to assemble activity flags of different CG configurations in chronological order to form the activity pattern reports.

In accordance with embodiments (see for example claim 17),

• each CG instance carrying a CG message from the apparatus includes a unique message, or

• a plurality (k) of CG instances carrying a CG message from the apparatus include an initial CG message and one or more repetitions of the initial CG message, the repetitions including a copy of the initial CG message or a predefined redundancy version of the initial CG message, and

• wherein the apparatus is to

• treat every CG instance carrying a CG message from the apparatus as a distinct message, and increment a counter associated with the predefined number (N, Q, T, S, M R) for each CG transmission by the apparatus, or

• treat CG instances carrying an initial CG message or one or more repetitions of the initial CG message as the same message, increment a counter associated with the predefined number (N, Q, T, S, M, R) for the CG transmission of the initial CG message by the apparatus and maintain the counter unchanged for CG transmissions performed by the apparatus that are repetitions of the initial CG message.

ENTITY RECEIVING THE CG TRANSMISSION

The present invention provides (see for example claim 18) an apparatus for a communication with a transmitter in a wireless communication system, wherein the apparatus is to receive one or more configured grant, CG, messages from at least one transmitter using one or more CG transmissions, and receive feedback related to the one or more CG transmissions from the transmitter.

In accordance with embodiments (see for example claim 19), the feedback related to the one or more CG transmissions includes one or more of:

• information associated with at least a number of CG transmissions performed by the apparatus during a certain time or period, • an activity pattern report, the activity pattern report indicating a number of CG transmissions and a usage status of each CG instance in a certain period, the usage status indicating the actual resources on which the CG transmissions occurred.

In accordance with embodiments (see for example claim 20), responsive to the feedback related to the CG transmissions, the apparatus is to evaluate the reliability of the reception of the CG transmissions, and wherein, dependent on the reliability of the reception of the CG transmissions, the apparatus may adapt one or more parameters associated with the detection of the CG messages or may reconfigure the CG resources at least for the transmitter.

In accordance with embodiments (see for example claim 21), responsive to the feedback related to the CG transmissions, the apparatus is to calculate one or more achieved error rates associated with the CG transmissions, and to adapt one or more parameters associated with the detection of the CG messages received from the transmitter using the calculated error rates.

In accordance with embodiments (see for example claim 22), the one or more error rates include one or more of:

• a message error rate, MER, defined as a ratio of a number of message errors to a number of CG instances carrying a CG message from the transmitter, wherein a message error occurs when information bits associated with the usage of a CG instance by the transmitter are not received correctly at the apparatus,

• a false alarm rate defined as the ratio of a number of false alarm events to a number of CG instances not carrying a CG message from the transmitter, wherein a false alarm event occurs when the transmitter does not transmit on a CG instance, while the apparatus decides that the transmitter performed a transmission,

• a misdetection rate defined as a ratio of a number of misdetection events to a number of CG instances carrying a CG message from the transmitter, wherein a misdetection event occurs when the transmitter transmits on a CG instance, while the apparatus decides that the transmitter performed no transmission.

In accordance with embodiments (see for example claim 23), the apparatus is to

• receive, in a control channel or in a data channel between the apparatus and the transmitter, like the PDCCH, the PDSCH, the PUCCH, the PUSCH, the PSCCH or the PSSCH, a feedback message each time a predefined number (N) of CG transmissions has been transmitted, and

• determine, based on the knowledge of the predefined number (N), a number of successful or non-successful receptions of CG messages.

In accordance with embodiments (see for example claim 24),

• a header of a predefined number (Q) of CG transmissions includes a flag, e.g., a one- bit flag, being set to a first value in all but the last of the CG transmissions, and being set to a second value in the last CG transmission, and the apparatus is to determine, based on the knowledge of the predefined number (Q), a number of successful or non-successful receptions of CG messages, or

• a header of a predefined number (Q) of CG transmissions includes a flag, e.g., a one- bit flag, a value of the flag changing each time the predefined number (Q) of CG transmissions has been transmitted, and the apparatus is to determine, based on the knowledge of the predefined number (Q), a number of successful or non-successful receptions of CG messages.

In accordance with embodiments (see for example claim 25), the apparatus is to decode the flag, the flag being encoded as a modification of a subset of cyclic redundancy check,

CRC, bits.

In accordance with embodiments (see for example claim 26), the apparatus is to

• receive a feedback message every predefined number (T) of CG transmission instances and the feedback message contains a number of CG instances carrying a CG message from the transmitter in the predefined number (T) of CG transmission instances, and

• determine, based on the knowledge of the predefined number (T), a number of successful or non-successful receptions of CG messages

In accordance with embodiments (see for example claim 27), the apparatus is to

• receive, responsive to a request to the transmitter, a report containing a number of CG instances carrying a CG message from the transmitter in a predefined number (S) of past CG transmission instances, or

• a report containing a number of CG instances carrying a CG message from the transmitter in a predefined number (S) of future CG transmission instances, • determine, based on the knowledge of the predefined number (S), a number of successful or non-successful receptions of CG messages.

In accordance with embodiments (see for example claim 28), the apparatus is to receive the feedback message in a control channel or in a data channel between the apparatus and the receiver, like the PDCCH, the PDSCH, the PUCCH, the PUSCH, the PSCCH or the PSSCH.

In accordance with embodiments (see for example claim 29), the one or more CG messages are numbered so that a CG message has associated therewith a certain sequence number, and wherein the apparatus is to receive from the transmitter a CG message together with its associated sequence number, and to determine, based on the knowledge of the sequence numbers, a number of successful or non-successful receptions of CG messages.

In accordance with embodiments (see for example claim 30), the apparatus is to

• retrieve from a CG message a sequence number represented by a predefined number (M) of bits, or

• decode the sequence number, the sequence number being encoded into the CG message, e.g., as a modification of a subset of cyclic redundancy check, CRC, bits.

In accordance with embodiments (see for example claim 31 ), the apparatus is to receive an activity pattern report providing the CG activity information over a predefined number (R) of transmitted CG transmission instances, and to determine, based on the knowledge of the predefined number (R), a number of successful or non-successful receptions of CG messages, a number of false alarm events, a number of misdetection events.

In accordance with embodiments (see for example claim 32), the apparatus is to request the activity pattern report from the transmitter.

In accordance with embodiments (see for example claim 33), the apparatus is to acknowledge to the transmitter the reception of the feedback message.

In accordance with embodiments (see for example claim 34), the apparatus is to

• send a plurality of different CG configurations defining different sets of CG resources in the time-frequency plane, like different subframes; available for CG transmissions, like RRC messages, Layer1/Layer2 messages or a broadcast message, and • receive a distinct feedback for each of the CG configurations, or a combined feedback for the plurality of the CG configurations.

GENERAL

In accordance with embodiments (see for example claim 35), the predefined number (N, Q, T, S, M R) is fixed or is configured by signaling, e.g., via a specific RRC signaling, like a ConfiguredGrantConfig message, via a Layer1/Layer2 signaling, like a PDCCH, PSCCH, or via a broadcast.

In accordance with embodiments (see for example claim 36), transmitting of the feedback message is enabled responsive to receiving a parameter associated with the predefined number (N, Q, T, S, M R) in a configuration message, like an RRC message, a Layer /Layer2 message or a broadcast message.

In accordance with embodiments (see for example claim 37), transmitting of the feedback message is disabled, in case the configuration message does not include a value for the parameter or includes a certain value for the parameter.

In accordance with embodiments (see for example claim 38), a parameter associated with the predefined number (N, Q, T, S, M, R) is communicated using a configuration message, like an RRC message, a Layer! /Layer2 message or a broadcast message, and wherein transmitting of the feedback message is enabled responsive to a flag in the configuration message.

In accordance with embodiments (see for example claim 39), the configuration message includes one or more of:

• a configuration causing a feedback message to be transmitted after every N CG transmissions,

• a configuration causing a flag, e.g., a one-bit flag, to be added to a header of the CG transmissions or to be encoded in a subset of the CRC bits, and to be

o set to a first value in Q-1 CG transmissions, and to a second value in the Q ^th CG transmission, or

o changed after every Q CG transmissions so as to indicate that Q CG messages have been transmitted since a last change of the value of the flag, • a configuration causing a transmission of a feedback message every T CG transmission instances, wherein the feedback message contains a number of CG instances carrying a CG message in the last T CG transmission instances,

• a configuration causing to send, responsive to a request,

o a report containing a number of CG instances carrying a CG message in last S CG transmission instances, or

o a report containing a number of CG instances carrying a CG message in next S CG transmission instances,

• a configuration causing a CG message to be to transmitted together with its associated sequence number,

• a configuration causing an activity pattern report to be transmitted, the activity pattern report providing the CG activity information over the latest R CG transmissions.

In accordance with embodiments (see for example claim 40), a CG transmission uses a CG instance, the CG instance comprising one or more defined resources, like configured time- frequency resources or positions, for the CG transmissions.

In accordance with embodiments (see for example claim 41), the time-frequency resources for the CG transmissions are preconfigured, e.g., via Radio Resource Control, RRC, signaling, or via RRC signaling and L1/L2 signaling.

In accordance with embodiments (see for example claim 42), the apparatus comprises a UE and the receiver comprises a gNB, or the apparatus comprises a gNB and the receiver comprises a UE, or the apparatus comprises a first UE and the receiver comprises a second UE, the first and second UEs to communicate over a sidelink.

In accordance with embodiments (see for example claim 43), the apparatus comprises a user device, UE, the UE comprising one or more of a mobile terminal, or stationary terminal, or cellular loT-UE, or vehicular UE, or vehicular group leader (GL) UE, an loT or narrowband loT, NB-loT, device, or a ground based vehicle, or an aerial vehicle, or a drone, or a moving base station, or road side unit, or a building, or any other item or device provided with network connectivity enabling the item/device to communicate using the wireless communication network, e.g., a sensor or actuator, or a base station or gNB, the base station comprising one or more of a macro cell base station, or a small cell base station, or a central unit of a base station, or a distributed unit of a base station, or a road side unit, or a UE, or a group leader (GL), or a relay, or a remote radio head, or an AMF, or an SMF, or a core network entity, or mobile edge computing entity, or a network slice as in the NR or 5G core context, or any transmission/reception point, TRP, enabling an item or a device to communicate using the wireless communication network, the item or device being provided with network connectivity to communicate using the wireless communication network.

SYSTEM

The present invention provides (see for example claim 44), a wireless communication system, comprising a plurality of the inventive apparatus.

METHODS

The present invention provides (see for example claim 45) a method for a communication with a receiver in a wireless communication system, the method comprising: transmitting one or more configured grant, CG, messages to at least one receiver using one or more CG transmissions, and transmitting feedback related to the one or more CG transmissions to the receiver.

The present invention provides (see for example claim 46) a method for a communication with a transmitter in a wireless communication system, the method comprising: receiving one or more configured grant, CG, messages from at least one transmitter using one or more CG transmissions, and receiving feedback related to the one or more CG transmissions from the transmitter.

COMPUTER PROGRAM PRODUCT

The present invention provides a computer program product comprising instructions which, when the program is executed by a computer, causes the computer to carry out one or more methods in accordance with the present invention. Embodiments of the present invention are now described with reference to a wireless communication system, like the one described above in Fig. 1 and Fig. 2. In the subsequent description it is assumed that a UE is provided that uses, for uplink transmission to the gNB, especially for low latency applications, CG transmissions, in other words, for the uplink, the UE is the entity performing the CG transmissions, while the base station or gNB is the entity receiving the CG transmissions. However, the present invention is not limited to such embodiments, rather, the embodiments described hereinbelow may be equally applied for CG transmissions in the downlink, i.e., for transmission from the gNB to a UE or to a plurality of UEs. In other words, in the downlink scenario, the gNB is the entity performing the CG transmission while the one or more UEs are the entities receiving the CG transmissions and estimate the reliability thereof so as to allow for a reliable receipt of the messages from the gNB.

It is further noted that the inventive approach is not limited to uplink or downlink transmissions, rather, the inventive approach as described in the subsequent embodiments may equally be applied for sidelink communications, i.e., for CG transmissions over a sidelink. In accordance with such embodiments, a UE may transmit directly to another UE over a sidelink. In such embodiments, the entity transmitting the CG transmission is a first UE, also referred to as the transmitting UE of the sidelink, and the entity receiving the CG transmission is a second UE, also referred to as a receiving UE of the sidelink which may evaluate the reliability of the CG transmission over the sidelink in a way as described below so as to take countermeasures, if needed.

In accordance with embodiments of the present invention, a report is introduced that is provided by the UE so as to allow the gNB to calculate the achieved error rates to a certain degree of accuracy. More specifically, in accordance with embodiments, the UE may report a history of CG transmissions, for example periodically or upon a request from the gNB. For example, the history may include a number of CG transmissions in the last x milliseconds, or each CG message may be associated with a consecutive number so as to allow the gNB to determine the actual numbers of CG messages received, for example, by a using a n-bit sequence number in each CG message. These embodiments and further embodiments are described in more detail below.

Responsive to the UE report, the gNB may monitor the health of the CG transmissions so as to know, for example, the false alarm rate or other error rates so that the gNB may adjust, for example, parameters of a detection algorithm, in case of a deviation of the respective rates from predefined target values. In accordance with embodiments, when the deviations are too high, the gNB may also consider the currently used resources for the CG transmission to be not suited anymore and may reconfigure one or more of the UEs to use other, collision-free resources. In other words, in accordance with the present invention, the gNB may use the information obtained from the UE so as to gain confidence that the CG transmissions meet certain reliability requirements, and in case this is no longer given, the UE may adapt for example the false alarm operating point of a detection algorithm towards a desired target value. This, in accordance with the present invention, is enabled by providing an explicit or implicit feedback related to CG transmissions by the UE.

In the following, several embodiments for providing the feedback from the UE to the gNB are described in more detail.

In accordance with embodiments, the feedback related to the one or more CG transmissions may include information associated with at least a number of CG transmissions performed by the apparatus during a certain time or period, or an activity pattern report, which indicates a number of CG transmissions and a usage status of each CG instance in a certain period. Other than the mere information about the number of CG transmissions, the usage status may also indicate the actual resources on which the CG transmissions occurred. Responsive to the feedback, the gNB may evaluate the reliability of the reception of the CG transmissions and, dependent on the reliability, the gNB may adapt one or more parameters associated with the detection of the CG messages or may reconfigure the CG resources to be used by a UE for transmitting the CG messages. For example, responsive to the feedback, the gNB may calculate the message error rate, the false alarm rate or the misdetection rate so as to adapt the detection parameters associated with detecting the CG messages accordingly so as to bring the error rates towards the target values discussed above.

In accordance with embodiments, the feedback may be a counter-triggered UE report. The UE may transmit a message in the uplink control channel or the uplink data channel every N CG transmissions. Fig. 5 illustrates an embodiment for providing a counter-triggered UE report where N is selected to be 5. Fig. 5 illustrates the used CG instances 400 and the unused CG instances 402, i.e. , those instances 400 in which the UE transmits a CG message and those instances 402 in which no CG transmission is performed by the UE, for example, because there is no data to be transmitted. As is indicated in Fig. 5, during the depicted time interval, initially there are three used CG instances, where respective transmissions of messages from the UE towards the gNB occur, followed by four unused CG instances, where no transmissions of messages from the UE towards the gNB occur. Another two used CG instances follow. Since N is selected to be 5, following the fifth used CG instance the UE creates a CG report 4041 at a time t1 and transmits the report to the gNB. Responsive to the report 404i, the gNB may estimate or calculate the reliability of the transmissions so as to adapt, if necessary, any parameters in the detection mechanism for detecting messages transmitted from the UE to the gNB during the used CG instances.

Fig. 5 further illustrates, following the time t1 , three used CG instances followed by four unused CG instances. Then another used CG instance occurs followed by three unused CG instances. Then a fifth used CG instance 400s occurs. At a time t2 following the fifth used CG instance a further CG report 404 ₂ is created or generated at the UE and transmitted to the gNB.

As may be seen from Fig. 5, the intervals between the CG reports 404i and 404 ₂ are not the same, rather they depend on the number of unused CG instances so that the time period from to to t1 is shorter than the time period from t1 to t2.

In accordance with embodiments, N has a large value, for example, N = 100, 500, 1000, so as to avoid, on the one hand, a signaling overhead associated with transmitting the CG report to the gNB, and, on the other hand, unnecessary action at the gNB in case of a low target for the alarm rate.

The value of N may be a fixed value or may be a value configured, for example, by the gNB. The configuration may be done via a UE specific RRC signaling, for example using a ConfiguredGrantConfig message as described in reference [2], In accordance with other embodiments, a Layer1/Layer2 signaling may be used, for example via the PDCCH. Also a broadcast information available for all UEs within the coverage of the gNB may be used for transmitting or configuring the value N at the UE.

Enabling the transmission of UE reports may be signaled in various ways, for example by including into a configuration message the parameter N, like into the above-mentioned RRC message, Layer1/Layer2 message or broadcast message. The transmission of the CG feedback may be enabled in case the configuration message includes one or more values for the parameter N. On the other hand, the CG feedback may be disabled in case the configuration message does not include a N value or in case a certain, predefined value is used thereby indicating that no CG feedback reporting is needed or required by the network. In accordance with other embodiments, the configuration message may include an additional flag, besides the value N, so as to indicate, dependent on the status of the flag, whether reporting the CG feedback is desired or not.

A message forwarding the CG feedback includes an identification as a CG report, for example by providing a specific field or the like in the header of the message, and reception of the message may be acknowledged by the gNB to the UE so as to ensure reliability of the transmission of the report information or feedback information.

Counter-Triggered Flag

In accordance with other embodiments, a counter-triggered flag may be used for reporting the feedback from the UE to the gNB. The UE may add a one-bit flag to the header of the respective CG transmissions.

In accordance with an embodiment, in most transmissions, the flag has first value, like 0, and after every Q CG transmissions, i.e., after Q transmissions have been made at the UE, the flag may set to a second value, like 1 , to indicate that Q CG message have been transmitted since the last value equal one flag.

In accordance with another embodiment, a differential signaling may be employed meaning that the flag stays at the first value, like 0, for Q transmissions, then changes for Q transmissions to the second value, like 1 , and then changes back for Q transmission to the first value and so on.

When considering, for example, high SNRs, the misdetection rate and the BLER are expected to be low and to meet the target values, despite any deviations in the model used for determining the detection algorithm. Therefore, the flag is correctly received at the gNB with a high probability. This allows addressing the above discussed issue regarding high false alarm rates at the high SNRs which, on the basis of the reliably received flags may be measured by the gNB.

The value of Q may be a fixed value or may be a value configured, for example, by the gNB. The configuration may be done via a UE specific RRC signaling, for example using a ConfiguredGrantConfig message as described in reference [2]. In accordance with other embodiments, a Layer /Layer2 signaling may be used, for example via the PDCCH. Also a broadcast information available for all UEs within the coverage of the gNB may be used for transmitting or configuring the value Q at the UE.

Enabling the transmission of UE reports may be signaled in various ways, for example by including into a configuration message the parameter Q, like into the above-mentioned RRC message, Layer! /Layer2 message or broadcast message. The transmission of the CG feedback may be enabled in case the configuration message includes one or more values for the parameter Q. On the other hand, the CG feedback may be disabled in case the configuration message does not include a Q value or in case a certain, predefined value is used thereby indicating that no CG feedback reporting is needed or required by the network. In accordance with other embodiments, the configuration message may include an additional flag, besides the value Q, so as to indicate, dependent on the status of the flag, whether reporting the CG feedback is desired or not.

A message forwarding the CG feedback includes an identification as a CG report, for example by providing a specific field or the like in the header of the message, and reception of the message may be acknowledged by the gNB to the UE so as to ensure reliability of the transmission of the report information or feedback information.

Periodic/Timer-Based UE Report

In accordance with yet other embodiments, the UE feedback may include a periodic or timer-based report. The UE may transmit a message in the uplink control channel or in the uplink data channel after every T CG transmission instances.

Fig. 6 illustrates an embodiment of using periodic/timer-based UE reports assuming T to be 5. Fig. 6 illustrates CG instances over a certain time period and, like Fig. 5, illustrates the used CG instances 400 and the unused CG instances 402. When T is set to be 5, following every fifth CG instance, the UE will create and transmit a CG report. In the embodiment depicted in Fig. 6, at a time t1 and assuming T to 5, the CG report generated and transmitted at the time t1 from the UE to the gNB indicates a value of three CG messages, i.e., the three used CG instances carrying a message between to and t1. Fig. 6 illustrates a second CG report 404 ₂ as well as a third and fourth CG report 404 ₃ , 404 ₄ created and transmitted at times t2, t3 and t4, respectively. Each value indicates the number of used CG instances or CG instances carrying a message in the last T = 5 CG instances so that CG report 404 ₂ has a value of three, CG report 404 ₃ has a value of two and CG report 404 ₄ has a value of one. In other words, the feedback message reports the number of used CG instances in the last T CG transmission instances.

The value of T may be a fixed value or may be a value configured, for example, by the gNB. The configuration may be done via a UE specific RRC signaling, for example using a ConfiguredGrantConfig message as described in reference [2] In accordance with other embodiments, a Layer1/Layer2 signaling may be used, for example via the PDCCH. Also a broadcast information available for all UEs within the coverage of the gNB may be used for transmitting or configuring the value T at the UE.

Enabling the transmission of UE reports may be signaled in various ways, for example by including into a configuration message the parameter T, like into the above-mentioned RRC message, Layer1/Layer2 message or broadcast message. The transmission of the CG feedback may be enabled in case the configuration message includes one or more values for the parameter T. On the other hand, the CG feedback may be disabled in case the configuration message does not include a T value or in case a certain, predefined value is used thereby indicating that no CG feedback reporting is needed or required by the network. In accordance with other embodiments, the configuration message may include an additional flag, besides the value T, so as to indicate, dependent on the status of the flag, whether reporting the CG feedback is desired or not.

A message forwarding the CG feedback includes an identification as a CG report, for example by providing a specific field or the like in the header of the message, and reception of the message may be acknowledged by the gNB to the UE so as to ensure reliability of the transmission of the report information or feedback information. gNB-Triggered UE Report

In accordance with further embodiments, the feedback may be triggered by a request of the gNB received at the UE. For example, the gNB may send a message to the UE to report a summary of CG transmissions, for example a summary of the last S CG transmissions.

Fig. 7 illustrates an embodiment of a gNB-triggered UE report for S = 5 prior CG instances so that the feedback or report provides activity information for the S CG instances before or prior to the gNB request. In Fig. 7, in a similar way as in Fig. 5, used and unused CG instances 400, 402 are illustrated over a certain period. In the embodiment depicted in Fig. 7, initially there are three consecutive used CG instances, followed by four unused CG instances which, in turn, are followed by five used CG instances. At a time t1 , the UE receives a gNB request 406i requesting from the UE to report a summary of the last S - 5 CG transmissions. The last S =5 transmissions are indicated at 408i and there are two used CG instances, i.e., two CG messages were transmitted by the UE to the gNB. The UE creates a respective CG report including a value of 2, indicating that in the requested time period two CG messages were uploaded and the CG report 404i is reported to the gNB at the time t2. As is further illustrated in Fig. 7, at a later time t3 another gNB request 406 ₂ is received at the UE, and the last S = 5 CG transmissions are indicated at 408 ₂ . During the last five CG instances, one used CG instance occurred so that the UE creates a CG report 404 ₂ indicating a value of 1 meaning that one CG message has been transmitted, and the CG report is forwarded to the gNB at a time t4.

In accordance with another embodiment of the gNB-triggered UE report, the gNB may send a message to the UE to report a summary, however, in accordance with this embodiment, the gNB requests a summary of the next S or the future S CG transmissions.

Fig. 8 illustrates an embodiment of using a gNB-triggered UE report for S = 5 future CG instances so that the activity information is provided for the S = 5 CG instances following the gNB request. Fig. 8 illustrates the used and unused CG instances 400, 402 over a time window. At a time t1 , the UE receives the gNB request 406i requesting the activity information for the next S = 5 CG instances as indicated at 408i. After the next S = 5 CG instances, the UE creates the CG report 404i indicating a value of 4 meaning that following the receipt of the gNB request 406i there were four used CG instances. The CG report 404i is transmitted to the gNB at a time t2 following the fifth CG instance since the time t1. Fig. 8 further illustrates that at a time t3, a further gNB request 406 ₂ is received requesting, again for S = 5 CG instances, as indicated at 408 ₂ , the activity report. Following the occurrence of the five CG instances, the UE creates the CG report 404 ₂ now indicating a value of 2, i.e., there were used CG instances in the last five CG instances from the receipt of the gNB request 406 ₂ at the time t3. At the time t4, the gNB report 404 ₂ is transmitted from the UE to the gNB.

In accordance with embodiments, the gNB reports 4041 , 404 ₂ may be transmitted by the UE to the gNB through the uplink control channel, like the PUCCH, or though the uplink data channel, like the PUSCH. The value of S may be a fixed value or may be a value configured, for example, by the gNB. The configuration may be done via a UE specific RRC signaling, for example using a ConfiguredGrantConfig message as described in reference [2], In accordance with other embodiments, a Layer1/Layer2 signaling may be used, for example via the PDCCH. Also a broadcast information available for all UEs within the coverage of the gNB may be used for transmitting or configuring the value S at the UE.

Enabling the transmission of UE reports may be signaled in various ways, for example by including into a configuration message the parameter S, like into the above-mentioned RRC message, Layer1/Layer2 message or broadcast message. The transmission of the CG feedback may be enabled in case the configuration message includes one or more values for the parameter S. On the other hand, the CG feedback may be disabled in case the configuration message does not include a S value or in case a certain, predefined value is used thereby indicating that no CG feedback reporting is needed or required by the network. In accordance with other embodiments, the configuration message may include an additional flag, besides the value S, so as to indicate, dependent on the status of the flag, whether reporting the CG feedback is desired or not.

A message forwarding the CG feedback includes an identification as a CG report, for example by providing a specific field or the like in the header of the message, and reception of the message may be acknowledged by the gNB to the UE so as to ensure reliability of the transmission of the report information or feedback information.

Sequence-Numbered Messages

In accordance with yet further embodiments, sequence-numbered messages may be employed.

In accordance with embodiments, the UE may attach a M-bit number as a part of the CG message indicating the actual number of the CG transmission. The value of the M-bit number may indicate a sequence number in the range of (0, ... , 2 ^M_1 ) that may be represented using the M-bits. Fig. 9 illustrates the use of sequence-numbered messages in accordance with embodiments, with the value of M set to be 3, i.e., three bits are used for indicating an actual number of the CG transmission. Fig. 9 illustrates the used and unused CG instances 400, 402 and that each used CG instance has associated a sequence number x which, in the depicted embodiment, has a value between 0 and 7 because a three-bit number is used. In other words, each of the CG messages that is transmitted at the used CG instances to the gNB has associated a specific sequence number, like 0, 1 , .... 7. More specifically, over the illustrated time period, initially three CG messages having the sequence numbers 0, 1 , 2 are transmitted at the shown used CG instances, and the following four instances are not used, i.e., do not carry a CG message. Then, five CG messages are transmitted in the following five consecutive CG instances, namely messages 3, 4, 5, 6 and 7.

When considering, for example, high SNRs, the misdetection rate and the BLER are expected to be low and to meet the target values, despite any deviations in the model used for determining the detection algorithm. Therefore, the sequence number is correctly received at the gNB with a high probability. This allows addressing the above discussed issue regarding high false alarm rates at the high SRNs which, on the basis of the reliably received sequence numbers may be measured by the gNB.

The value of M may be a fixed value or may be a value configured, for example, by the gNB. The configuration may be done via a UE specific RRC signaling, for example using a ConfiguredGrantConfig message as described in reference [2], In accordance with other embodiments, a Layer1/Layer2 signaling may be used, for example via the PDCCH. Also a broadcast information available for all UEs within the coverage of the gNB may be used for transmitting or configuring the value M at the UE.

Enabling the transmission of UE reports may be signaled in various ways, for example by including into a configuration message the parameter M, like into the above-mentioned RRC message, Layer1/Layer2 message or broadcast message. The transmission of the CG feedback may be enabled in case the configuration message includes one or more values for the parameter M. On the other hand, the CG feedback may be disabled in case the configuration message does not include a M value or in case a certain, predefined value is used thereby indicating that no CG feedback reporting is needed or required by the network. In accordance with other embodiments, the configuration message may include an additional flag, besides the value M, so as to indicate, dependent on the status of the flag, whether reporting the CG feedback is desired or not.

In accordance with other embodiments of the sequence-numbered messages, rather than using the above-described M-bit number as part of the CG message, the sequence number may be encoded into the CG message, for example, it may be implicitly encoded as a modification of a subset of the cyclic redundancy check, CRC, bits which is a function of the sequence number. The encoding may be performed using scrambling, XOR-ing or the like.

UE Activity Pattern Report

In accordance with yet another embodiment, the UE may provide a UE activity pattern report. The UE activity pattern report may provide a full activity information over the latest R CG transmission instances. The creation and the transmission of the activity pattern report may be triggered by a respective request issued by the gNB, or by a timer, or by a counter indicating a number of used CG instances, i.e., a counter counting the number of actual CG transmissions. The report may include a R-bit message in which a bit position uniquely identifies a CG instance in the latest R CG transmission instances, and the value of the bit indicates whether the corresponding CG instance was used or not, i.e., whether at a certain instance a CG message was transmitted by the UE or not.

In accordance with embodiments, values of R may be high, for example R = 100, 500, 1000, ... and the report may be sent over the uplink data channel or the uplink control channel including an identification indicating that it is the activity pattern report to be used for evaluating the reliability of the CG transmissions at the gNB. In other words, the R-bit information may be considered as a transport block generated at the physical layer.

The value of R may be a fixed value or may be a value configured, for example, by the gNB. The configuration may be done via a UE specific RRC signaling, for example using a ConfiguredGrantConfig message as described in reference [2], In accordance with other embodiments, a Layer1/Layer2 signaling may be used, for example via the PDCCH. Also a broadcast information available for all UEs within the coverage of the gNB may be used for transmitting or configuring the value R at the UE.

Enabling the transmission of UE reports may be signaled in various ways, for example by including into a configuration message the parameter R, like into the above-mentioned RRC message, Layer1/Layer2 message or broadcast message. The transmission of the CG feedback may be enabled in case the configuration message includes one or more values for the parameter R. On the other hand, the CG feedback may be disabled in case the configuration message does not include a R value or in case a certain, predefined value is used thereby indicating that no CG feedback reporting is needed or required by the network. In accordance with other embodiments, the configuration message may include an additional flag, besides the value R, so as to indicate, dependent on the status of the flag, whether reporting the CG feedback is desired or not.

Modification for k Repetitions

The above embodiments concerning the counter-triggered UE report, the counter-triggered flag, the periodic/timer-based UE report, the gNB-triggered UE report, the sequence- numbered messages and the UE activity pattern report assumed that that each of the used CG instances carries a unique message, like a transport block. However, in accordance with embodiments, the CG transmission may include one or more repetitions, for example, a certain message, also referred to as an initial CG message, may be repeated k times. Each repetition of the initial message may be a certain redundancy version of the initial message, like a copy of the message or a message including the same bits or more or less bits of the codeword corresponding to the message. The above-described embodiments may implement the repetition of the CG messages as follows:

1. With regard to the reporting, the setting of the flags and the generation of the sequence numbers, the UE may treat every used CG instance as being distinct, whether it is a repetition or not, and the respective counter values and/or sequence numbers may be incremented for each use of the CG instance by the UE, i.e., for each transmission of CG message during a CG instance.

2. With regard to the reporting, the setting of the flags and the generation of the sequence numbers, the UE may only consider the unique messages, i.e., the counter values and/or sequence numbers remain the same in case a CG message is a repetition of an initial CG message by the UE.

Modification for Multiple CG Configurations

In accordance with further embodiments, multiple CG configurations may be used for a UE. Each CG configuration may define a specific set of resources, like subframes, in the time- frequency plane for the CG instances. For example, when considering a scenario using two CG configuration, the first CG configuration may allocate resources for the CG transmission every 5 ^th subframe so that CG transmissions may occur in the 5 ^th subframe, the 10 ^th subframe, the 15 ^th subframe and so on. The second first CG configuration may also allocate resources for the CG transmission every 5 ^th subframe but starting at a different subframe, like the 2 ^nd subframe, so that CG transmissions may occur in the 2 ^nd subframe, the 7 ^th subframe, the 12 ^th subframe and so on. In other words, having multiple configurations allows interlacing the CG instances of different configurations in the time direction, which may further reduce the latency.

For example, when considering the above scenario of two configurations and the above described embodiments using a counter, like the counter-triggered UE report embodiment, the counter-triggered flag embodiment, the periodic/timer-based UE report embodiment, and the gNB-triggered UE report embodiment, the UE may transmit CG messages on the resources, like subframes, as defined by the two configurations. For example, the UE may transmit a CG message in subframes 1 and 5 of the first CG configuration so that the counter associated with the first CG configuration is 2, and a CG message in subframe 2 of the second CG configuration so that the counter associated with the second CG configuration is 1.

When considering the above scenario of two configurations and the above described embodiments using sequence-numbered messages, the UE may transmit CG messages on the resources, like subframes, as defined by the two configurations. For example, the UE may transmit a CG message in subframes 1 and 5 of the first CG configuration so that the sequence-numbers associated with the first CG configuration are 1 and 2, and a CG message in subframe 2 of the second CG configuration so that the sequence-number associated with the second CG configuration is 1.

In accordance with embodiments, the UE may provide a distinct feedback for each of the different configurations. When providing the distinct feedback, the UE may keep distinct reports/flags/sequence numbers, as described in the above embodiments for different configurations, using the parameters N, Q, T, S, M or R as specified for the respective CG configurations by the gNB (e.g., via RRC signaling or via broadcast information). This also allows the gNB to decide which CG configurations is to be selected for the feedback, e.g., by not including any values for the parameters for those configurations no desired. In the above described examples using two configurations and the counters, the distinct feedback reports for the first CG configuration a value of a first counter to be 2, and reports for the second CG configuration a value of a second counter to be 1. Likewise, in the above described examples using two configurations and the sequence numbers, the distinct feedback reports for the first CG configuration a first sequence of numbers {1 , 2}, and reports for the second CG configuration a first sequence of numbers {1}. In accordance with other embodiments, the UE may provide a combined feedback corresponding to the respective CG configurations. In the above described examples using two configurations and the counters, the combined feedback reports for the first and second CG configurations a value of a common counter to be 3. Likewise, in the above described examples using two configurations and the sequence numbers, the distinct feedback reports for the first and second CG configurations a combined sequence of numbers {1 , 2, 3}. When considering the above described embodiments, the UE may combine the counters/activity information corresponding to individual CG configurations as follows:

In case of the counter-triggered UE report embodiment, individual counters for each CG configuration may be provided, and the report may be sent when a sum of the individual counters equals to a positive integer multiple of N. The counter may be incremented in a way as described in the above-mentioned embodiment concerning the use of k repetitions of the message.

In case of the counter-triggered flag embodiment, individual counters for each CG configuration may be provided, and the flag may be set when the sum of the individual counters equals a positive integer number of Q. The counter may be incremented in a way as described in the above-mentioned embodiment concerning the use of k repetitions of the message.

In case of the periodic/time-based UE report embodiment or the gNB-triggered UE report embodiment, individual counters for each CG configuration may be provided, and the report includes a value equal to the sum of the counters (counting T or S). The counter may be incremented in a way as described in the above-mentioned embodiment concerning the use of k repetitions of the message.

In case of the sequence numbered embodiment, a single counter may be used to calculate the sequence numbers of messages of different CG configurations. The counter is incremented whenever a message is transmitted in any of the CG configurations. The counter may be incremented in a way as described in the above- mentioned embodiment concerning the use of k repetitions of the message.

In case of the UE activity pattern report embodiment, the one-bit activity flag of different CG configurations may be assembled in chronological order so as to form the UE activity pattern report.

GENERAL

With regard to the above-described embodiments of the various aspects of the present invention, it is noted that they have been described in an environment in which a communication is between a transmitter, like a gNB or a UE, and a receiver, like a UE and a gNB. However, the invention is not limited to such a communication, rather, the above- described principles may equally be applied for a device-to-device communication, like a D2D, V2V, V2X communication. In such scenarios, the communication is over a sidelink between the respective devices. The transmitter is a first UE and the receiver is a second UE communicating using the sidelink resources.

Embodiments of the present invention have been described in detail above, and the respective embodiments and aspects may be implemented individually or two or more of the embodiments or aspects may be implemented in combination.

Embodiments of the present invention have been described in detail above with reference to a uplink communication using, e.g., the Uu interface. However, the present invention is not limited to the use of the Uu interface. Any other interface allowing for a communication among a gNB and a UE (UL or DL) of for a direct communication among one or more UEs may be employed.

In accordance with embodiments, the wireless communication system may include a terrestrial network, or a non-terrestrial network, or networks or segments of networks using as a receiver an airborne vehicle or a spaceborne vehicle, or a combination thereof.

In accordance with embodiments, a receiver may comprise one or more of a mobile or stationary terminal, an loT device, a ground-based vehicle, an aerial vehicle, a drone, a building, or any other item or device provided with network connectivity enabling the item/device to communicate using the wireless communication system, like a sensor or actuator. In accordance with embodiments, a transmitter may comprise one or more of a macro cell base station, or a small cell base station, or a spaceborne vehicle, like a satellite or a space, or an airborne vehicle, like a unmanned aircraft system (UAS), e.g., a tethered UAS, a lighter than air UAS (LTA), a heavier than air UAS (HTA) and a high altitude UAS platforms (HAPs), or any transmission/reception point (TRP) enabling an item or a device provided with network connectivity to communicate using the wireless communication system.

Although some aspects of the described concept have been described in the context of an apparatus, it is clear that these aspects also represent a description of the corresponding method, where a block or a device corresponds to a method step or a feature of a method step. Analogously, aspects described in the context of a method step also represent a description of a corresponding block or item or feature of a corresponding apparatus.

Various elements and features of the present invention may be implemented in hardware using analog and/or digital circuits, in software, through the execution of instructions by one or more general purpose or special-purpose processors, or as a combination of hardware and software. For example, embodiments of the present invention may be implemented in the environment of a computer system or another processing system. Fig. 10 illustrates an example of a computer system 500. The units or modules as well as the steps of the methods performed by these units may execute on one or more computer systems 500. The computer system 500 includes one or more processors 502, like a special purpose or a general-purpose digital signal processor. The processor 502 is connected to a communication infrastructure 504, like a bus or a network. The computer system 500 includes a main memory 506, e.g., a random-access memory (RAM), and a secondary memory 508, e.g., a hard disk drive and/or a removable storage drive. The secondary memory 508 may allow computer programs or other instructions to be loaded into the computer system 500. The computer system 500 may further include a communications interface 510 to allow software and data to be transferred between computer system 500 and external devices. The communication may be in the from electronic, electromagnetic, optical, or other signals capable of being handled by a communications interface. The communication may use a wire or a cable, fiber optics, a phone line, a cellular phone link, an RF link and other communications channels 512.

The terms “computer program medium” and “computer readable medium” are used to generally refer to tangible storage media such as removable storage units or a hard disk installed in a hard disk drive. These computer program products are means for providing software to the computer system 500. The computer programs, also referred to as computer control logic, are stored in main memory 506 and/or secondary memory 508. Computer programs may also be received via the communications interface 510. The computer program, when executed, enables the computer system 500 to implement the present invention. In particular, the computer program, when executed, enables processor 502 to implement the processes of the present invention, such as any of the methods described herein. Accordingly, such a computer program may represent a controller of the computer system 500. Where the disclosure is implemented using software, the software may be stored in a computer program product and loaded into computer system 500 using a removable storage drive, an interface, like communications interface 510. The implementation in hardware or in software may be performed using a digital storage medium, for example cloud storage, a floppy disk, a DVD, a Blue-Ray, a CD, a ROM, a PROM, an EPROM, an EEPROM or a FLASH memory, having electronically readable control signals stored thereon, which cooperate (or are capable of cooperating) with a programmable computer system such that the respective method is performed. Therefore, the digital storage medium may be computer readable.

Some embodiments according to the invention comprise a data carrier having electronically readable control signals, which are capable of cooperating with a programmable computer system, such that one of the methods described herein is performed.

Generally, embodiments of the present invention may be implemented as a computer program product with a program code, the program code being operative for performing one of the methods when the computer program product runs on a computer. The program code may for example be stored on a machine readable carrier.

Other embodiments comprise the computer program for performing one of the methods described herein, stored on a machine readable carrier. In other words, an embodiment of the inventive method is, therefore, a computer program having a program code for performing one of the methods described herein, when the computer program runs on a computer.

A further embodiment of the inventive methods is, therefore, a data carrier (or a digital storage medium, or a computer-readable medium) comprising, recorded thereon, the computer program for performing one of the methods described herein. A further embodiment of the inventive method is, therefore, a data stream or a sequence of signals representing the computer program for performing one of the methods described herein. The data stream or the sequence of signals may for example be configured to be transferred via a data communication connection, for example via the Internet. A further embodiment comprises a processing means, for example a computer, or a programmable logic device, configured to or adapted to perform one of the methods described herein. A further embodiment comprises a computer having installed thereon the computer program for performing one of the methods described herein. In some embodiments, a programmable logic device (for example a field programmable gate array) may be used to perform some or all of the functionalities of the methods described herein. In some embodiments, a field programmable gate array may cooperate with a microprocessor in order to perform one of the methods described herein. Generally, the methods are preferably performed by any hardware apparatus.

The above described embodiments are merely illustrative for the principles of the present invention. It is understood that modifications and variations of the arrangements and the details described herein are apparent to others skilled in the art. It is the intent, therefore, to be limited only by the scope of the impending patent claims and not by the specific details presented by way of description and explanation of the embodiments herein.

Abbreviations

Abbreviation Meaning

CG Configured grant

URLLC Ultra-reliable low-latency communication

V2X Vehicle-to-everything

gNB 5G base-station

UE User equipment

SCI Sidelink control information

UCI Uplink control information

DCI Downlink control information

PRB Physical resource block

RA Resource allocation

□MRS Demodulation reference signal

MER Message error rate

BLER Block error rate

SNR Signal-to-noise ratio

SIR Signal-to-interference ratio

ACK Acknowledgement

NACK Negative acknowledgement

CRC Cyclic redundancy check

PDCCH Physical downlink control channel

PSCCH Physical sidelink shared channel

References

[1 ] 3GPP TS38.214, 3 ^rd Generation Partnership Project; Technical Specification

Group Radio Access Network; NR; Physical layer procedures for data (Release 15); V15.2.0

[2] 3GPP TS38.331 , 3 ^rd Generation Partnership Project; Technical Specification

Group Radio Access Network; NR; Radio resource control (Release 15); V15.4.0

[3] 3GPP TS38.21 1 , 3 ^rd Generation Partnership Project; Technical Specification

Group Radio Access Network; NR; Physical channels and modulation (Release 15); V15.1.0

[4] 3GPP TS38.213, 3 ^rd Generation Partnership Project; Technical Specification

Group Radio Access Network; NR; Physical layer procedures for control (Release 15); V15.2.0

[5] RP-190339, Status report to TSG“Study on physical layer enhancements for

NR ultra-reliable and low latency case (URLLG)”, 3GPP TSG RAN meeting #83, Shenzhen, China, March 2019

[6] R. Tandra and A. Sahai, "SNR Walls for Signal Detection," in IEEE Journal of

Selected Topics in Signal Processing, vol. 2, no. 1 , pp. 4-17, Feb. 2008.