MECHANISM OF CROSS-LAYER LINK ADAPTATION IN 5G BROADCAST/MULTICAST

CROSS REFERENCE TO RELATED APPLICATION:

[0001] This application claims the benefit of U.S. Provisional Application No. 62/822,377, filed March 22, 2019. The entire content of the above-referenced application is hereby incorporated by reference.

BACKGROUND:

Field:

[0002] Mobile communication systems may be associated with broadcast and/or multicast transmissions using higher layer error correction schemes.

Description of the Related Art:

[0003] In a long-term evolution (LTE) communications system, network multicast and/or broadcast services may operate according to a static configuration of layer 1 modulation and coding scheme (MCS) as a means to provide robustness against fading channel variations, where acknowledgement (ACK) / non-acknowledgement (NACK)-based error correction methods are either unused in the case of idle mode operation, or are operating inefficiently with multicast/broadcast services.

[0004] In an effort to provide further protection against fading variation, a system may provide an additional level of forward error correction (FEC), for example, as discussed in 3rd Generation Partnership Project (3GPP) TS 26.346, which describes application layer forward error correction (AL-FEC) based on Raptor codes as a second layer of error correction. AL-FEC may be implemented at application servers above a user datagram protocol (UDP) / internet protocol (IP) layer, which may principally allow an alleviation of MCS robustness yet in a static and uncontrolled manner.

SUMMARY:

[0005] In accordance with some embodiments, a method may include receiving, by a network entity, at least two measurement reports associated with point-to- multipoint on protocol data unit packet loss rate from at least two user equipment. The method may further include processing, by the network entity, the at least two measurement reports. The method may further include performing, by the network entity, cross-layer communication with at least one medium access control layer for modulation and coding scheme modification.

[0006] In accordance with some embodiments, an apparatus may include means for receiving at least two measurement reports associated with point-to- multipoint on protocol data unit packet loss rate from at least two user equipment. The apparatus may further include means for processing the at least two measurement reports. The apparatus may further include means for performing cross-layer communication with at least one medium access control layer for modulation and coding scheme modification.

[0007] In accordance with some embodiments, an apparatus may include at least one processor and at least one memory including computer program code. The at least one memory and the computer program code can be configured to, with the at least one processor, cause the apparatus to at least receive at least two measurement reports associated with point-to-multipoint on protocol data unit packet loss rate from at least two user equipment. The at least one memory and the computer program code can be further configured to, with the at least one processor, cause the apparatus to at least process the at least two measurement reports. The at least one memory and the computer program code can be further configured to, with the at least one processor, cause the apparatus to at least perform cross-layer communication with at least one medium access control layer for modulation and coding scheme modification.

[0008] In accordance with some embodiments, a non-transitory computer readable medium can be encoded with instructions that may, when executed in hardware, perform a method. The method may include receiving at least two measurement reports associated with point-to-multipoint on protocol data unit packet loss rate from at least two user equipment. The method may further include processing the at least two measurement reports. The method may further include performing cross-layer communication with at least one medium access control layer for modulation and coding scheme modification.

[0009] In accordance with some embodiments, a computer program product may perform a method. The method may include receiving at least two measurement reports associated with point-to-multipoint on protocol data unit packet loss rate from at least two user equipment. The method may further include processing the at least two measurement reports. The method may further include performing cross-layer communication with at least one medium access control layer for modulation and coding scheme modification.

[0010] In accordance with some embodiments, an apparatus may include circuitry configured to receive at least two measurement reports associated with point-to-multipoint on protocol data unit packet loss rate from at least two user equipment. The circuitry may further be configured to process the at least two measurement reports. The circuitry may further be configured to perform cross layer communication with at least one medium access control layer for modulation and coding scheme modification.

BRIEF DESCRIPTION OF THE DRAWINGS:

[0011] For proper understanding of this disclosure, reference should be made to the accompanying drawings, wherein:

[0012] FIG. 1 illustrates an example of processing packet loss rate (PER) measurements from multiple UEs according to certain embodiments. [0013] FIG. 2 illustrates an example of MCS modification procedures according to certain embodiments.

[0014] FIG. 3 illustrates an example of a cumulative distribution function of an application layer spectral efficiency according to certain embodiments.

[0015] FIG. 4 illustrates an example of a cumulative distribution function of an application layer packet loss rate according to certain embodiments.

[0016] FIG. 5 illustrates an example of a cumulative distribution function of an error correction packet data unit loss rate according to certain embodiments.

[0017] FIG. 6 illustrates an example of a cumulative distribution function of an application layer spectral efficiency according to certain embodiments.

[0018] FIG. 7 illustrates an example of a cumulative distribution function of an application layer packet loss rate according to certain embodiments.

[0019] FIG. 8 illustrates an example of a cumulative distribution function of error correction packet data unit loss rate according to certain embodiments.

[0020] FIG. 9 illustrates an example of a signaling diagram according to certain embodiments.

[0021] FIG. 10 illustrates another example of a signaling diagram according to certain embodiments.

[0022] FIG. 11 illustrates an example of a method performed by a network entity according to certain embodiments.

[0023] FIG. 12 illustrates an example of a system according to certain embodiments.

DETAILED DESCRIPTION:

[0024] Two FEC layers - PHY/MAC (lower layer) and AL (higher layer) - may operate independently, and may cause adverse interference situations, such as inefficient radio resource utilization, low spectral efficiency, diminished system performance. In order to improve system performance, AL-FEC may require a certain level of reliability of communication links, such as a 10% packet error rate, which may be achieved by using underlying protocols.

[0025] When user equipment does not provide the network with feedback of AL-FEC performance, MCS selection belonging to the lower layer FEC may only be based on the potentially worst condition that one of the served user equipment may experience. For example, this may be derived from lower layer link quality reports, such as channel quality indicator (CQI), without many drawbacks. However, short CQI reporting periodicity, in combination with a large number of user equipment using a broadcast/multicast service, may have the increased probability that one of the served user equipment may suffer from deep fading notch, and that a conservative MCS may have to be selected for desired cell coverage. In order to better cope with fading dips of individual UEs, AL-FEC may be designed to span periods considerably larger than the channel coherence time to allow for a higher MCS, thereby improving spectral efficiency. Short CQI reporting periodicity from a larger number of user equipment may also result in high signaling load.

[0026] Single conservative MCSs may cause UE to experience a targeted reliability level of communication links only when UE is at an edge of its cell’s coverage area. Within this coverage area, some UE may experience an improved communication link, such as with a lower than expected packet error rate. When a reliability level of communication of a worst user equipment link operates better than expected by the AL-FEC, AL-FEC coding may operate with excess redundancy, resulting in wasted system resources.

[0027] Although a larger reporting periodicity with quality indications of the application layer packets may alleviate some of these drawbacks, other problems may occur. For example, AL-FEC blocks are typically larger, and their duration in time may be longer compared to cycles where lower layer link adaptation operates, and may be used to derive a quality indication for MCS adaptation. There is currently no solution which allows a network to adapt lower layer MCS regulation based on feedback on larger AL-FEC blocks with such larger cycles.

[0028] 3GPP TS 36.890 discusses PTM with group-based uplink feedback for HARQ and link adaptation, such as CSI reporting. HARQ feedback messages may be reported from each UE to the network whenever a packet is received. However, the number of HARQ ACK/NACK messages increase with the number of UE, leading to a high feedback load in scenarios with a number of users where PTM is desirable. In response, this scalability problem may be addressed by operating only with NACK messages, as well as to allocate a shared uplink resource for group feedback. Furthermore, a HARQ-based solution is inefficient as the number of UE increases since packet loss events at different UE are statistically independent so that different UE may request retransmission of different packets.

[0029] US Patent Number 7,164,890 B2 discusses link adaptation for PTM according to feedback from UE. Feedback from UE is sent via a common uplink channel, and the network controller decides to modify MCS settings. However, while it is unclear which measurement types provide the best signal quality, there are limitations as to the scalability of feedback, and, for higher layer EC such as AL-FEC, there is no coordination between link adaptation and the higher layer EC.

[0030] Horizon 2020, an EU-funded 5G-Xcast project, is associated with a 2nd layer of EC in RAN, which may be located above or in the RLC layer. However, modification of MCS in coordination with the 2nd layer of EC in RAN has not been investigated. Due to its relation with ARQ schemes, an appropriate selection of the layer 1 MCS affects overall spectral efficiency. Thus, a mechanism which coordinates MCS modifications via cross-layer link adaptation (LA) at a scale comparable with a higher layer EC operation, such as AL-FEC or a 2nd of EC in RAN, is critical to maximize network efficiency, while also providing robustness to satisfy quality of experience (QoE) requirements.

[0031] As noted above, a link adaptation and hybrid automatic repeat request (HARQ) for point-to-multipoint (PTM) communication based on feedback from a group of user equipment may be one technique to respond to the above- mentioned challenges. Certain embodiments described herein may have various benefits and/or advantages to overcome the disadvantages described above by improving the efficiency of the radio resource management via tuning of the lower layer, as well as providing scalability due to less frequent feedback from user equipment. Furthermore, a link adaptation at a lower protocol layer is possible with less frequent feedback from user equipment, such as once per second, at a higher protocol layer and due to the application of EC at the higher protocol layer. As a result, certain embodiments may result in improved reliability and latency, and improvements in computer-related technology.

[0032] Certain embodiments described herein may relate to a coordination of higher layer EC, such as AL-FEC or layer 2 EC in RAN, and link adaption (LA), which may reselect the MCS of the lower layer FEC at a rate which is adapted to the AL-FEC transmission blocks. This may be slow compared with conventional PTP CQI-based link adaptation using a higher-layer EC PDU loss rate as the performance criterion. Specifically, a network may configure user equipment to perform measurements on EC PDU packet loss rates (PLR) within a higher-layer EC operational block. The higher-layer EC operational block may refer to a group of service data units (SDUs) over which higher layer EC may be applied to generate EC PDUs. The network then processes reports on PLR (with respect to the above-mentioned PDUs) measurements, which may be received from multiple UE. The network layer that hosts the higher layer EC may then determine whether more or less robust MCS should be used at the lower layer based on thresholds on the targeted PLR configured by the network. The MCS modification may be coordinated via cross-layer communication between the higher layer that hosts EC and the MAC layer where the MCS modification is applied, such as with requests from a higher layer protocol entity to a lower layer protocol entity via a service access point.

[0033] Certain methods described herein may also tune MCS such that the packet loss rate in the AL-FEC coded packets is below, but close, to the packet loss rate that the AL-FEC can handle, such as by reconstructing all higher layer packets.

[0034] The coordination may also comprise provisioning inform tion from the lower layer to the higher layer, with the higher layer modifying encoding parameters based on the information provided by the lower layer. For example, the lower layer may indicate that the most robust MCS is used, and in response, the higher layer may increase the amount of redundancy in error coding, improving quality of service with increased PLR.

[0035] In some embodiments, a network may apply error encoding at a higher layer protocol entity, wherein the higher layer protocol entity may be located either in a network node providing wireless access to the network, or another network node such as an application server, and error encoding at a lower layer protocol entity, which may be located in a network node providing wireless access. The network may configure user equipment receiving multicast/broadcast transmissions to measure packet loss rates at the higher layer protocol entity for higher-layer operational blocks of error coding.

[0036] In turn, the UE may report the measured packet loss rates either in a dedicated message, such as an RRC message, or piggy-backed to existing UL control or user data channel messages to the network. The network may process these higher layer PLR reports from the set of served UE to derive an indication that controls the lower layer protocol entity to select parameters for its error coding and transmission, such as MCS. The indication may be a request to increase/decrease the robustness of the encoding and transmission, and/or to select a particular MCS from a known set of MCS s, such as by using an index.

[0037] The lower layer protocol entity may indicate to the higher layer protocol entity that the MCS cannot be changed based on the input from the higher layer protocol entity, where the lowest MCS may already be in use and may not be lowered further, or that the lower layer protocol entity changed the MCS without a higher layer protocol entity input. The higher layer protocol entity may adjust the error encoding, either by increasing or decreasing the amount of redundancy in error coding, based on the indication from the lower layer protocol entity.

[0038] As described above, a higher-layer EC, such as AL-FEC or layer 2 EC, may perform successive or block-wise encoding on a block of EC service data units (SDUs), which may typically be grouped into blocks / generations. Certain embodiments contained herein may coordinate MCS modification with higher layer EC schemes. UE may then perform measurements on EC PDU PLR to monitor the PLR of EC PDUs within higher layer EC blocks. Event-based or periodic reporting may be used to deliver the PLR measurements from UE to the network via the physical uplink shared channel (PUSCH). The network may then process PLR measurement reports from multiple UE to adjust MCS settings that are to be used for PTM bearers which may be applied for transmission to all UE being served by the network.

[0039] UE may have various channel conditions, while in the MCS adjustment, PLR measurements may be received from multiple UE. The PLR measurement report from each UE may maintain a measurement report sequence number (SN) to provide information about the EC block SN that is measured. Before the network performs MCS adjustments, PLR measurement reports of the same SN may be received from all UE being served by the PTM bearer. To this end, the network may maintain a timer, such as a multiple user report timer, which may begin when the PLR measurement of a new SN is received from a UE. [0040] FIG. 1 illustrates a flowchart of a process performed by a RAN to process PLR measurements from multiple UE being served by PTM bearers. Upon reception of PLR measurement reports, the RAN may extract the report sequence number (SN), ‘rx report SN’, and the PLR measurement value, ‘rx PLR measurement’. The RAN may then update its current report SN, ‘current SN’, with the received report SN,‘rx report SN’. The current report SN ‘current SN’ may be compared with the previous report SN ‘previous SN’. If‘current SN’ is greater than‘previous SN’, it may signify reception of the first new measurement report from one of the UE. Consequently, the network may start‘multiple user report timer’ to monitor measurement reports with the same SN from multiple UE.

[0041] The network may also initialize the current maximum PLR value, ‘current max PLR value’, with received PLR measurement ‘rx PLR measurement,’ and may update previous report SN‘previous SN’ with the current report SN‘current SN.’ Alternatively, if the current report SN is not new, such as where‘current SN’ is not greater than‘previous SN,’ the network may compare the received PLR value,‘rx PLR measurement,’ with the current maximum PLR value, ‘current max PLR value’. If the received PLR value, ‘rx PLR measurement,’ is higher than the current maximum PLR value,‘current max PLR value’, the network may update the current maximum PLR value, ‘current max PLR value,’ with the received PLR value, ‘rx PLR measurement’. If not, the network may maintain the current maximum PLR value,‘current max PLR value.’

[0042] Upon expiration of timer‘multiple user report timer’, the network may perform a decision to update MCS settings. Accordingly, the network planner or operator may define PLR value thresholds at the RAN to compare with the current maximum PLR value. A higher threshold, ‘threshold higher,’ and lower threshold,‘threshold lower,’ may be defined to assist the network in determining whether to decrease or increase MCS settings, respectively. To avoid oscillations on the MCS settings, the lower threshold, ‘threshold lower,’ may be configured with a value lower than or equal to the higher threshold, ‘threshold higher.’ In the latter case where ‘threshold lower’ is equal to‘threshold higher,’ one threshold is effectively used.

[0043] FIG. 2 illustrates MCS modification procedures upon expiration of the ‘multiple user report timer’. If the current maximum (among all UEs) PLR value ‘current max PLR value’ is greater than higher threshold ‘threshold higher,’ the MCS setting may be decreased by MCS decrement offset‘mcs delta offset decrement.’ If not, the current maximum PLR value ‘current max PLR value’ may be compared with the lower threshold ‘threshold lower’. If the current maximum PLR value ‘current max PLR value’ is smaller than the lower threshold ‘threshold lower,’ the MCS setting may be incremented by MCS increment offset‘mcs delta offset increment.’

[00441 AL-FEC may improve robustness by sacrificing spectral efficiency compared with‘no EC,’ such as where AL-FEC is more than 95% of the cases and the application layer packet loss rate is lower than 0.1%; however, 20% spectral efficiency may be sacrificed for repair packets.‘AL-FEC + LA’ may provide similar robustness with improved spectral efficiency as compared to AL-FEC. For example, ‘AL-FEC + LA’ may allow a MCS setting modification at‘threshold higher.’‘THH = THL = 3%’ shows that, in more than 95% of the cases, the application layer packet loss rate may be lower than 0.1%, while the spectral efficiency sacrificed for repair packets may be compensated by an improved adaptation of MCS settings leading to no loss in spectral efficiency. With respect to‘AL-FEC + LA’ and the configuration of thresholds, configuration of higher values, such as THH = THL = 9 %, may lead to lower robustness at around 0.1% application packet loss rate as compared to ‘AL-FEC’ even though better spectral efficiency may be achieved by allowing aggressive modification of MCS setting by setting parameters THH and THL to a higher value.

[0045]‘2nd layer EC’ without LA may provide much higher robustness with small sacrifice on spectral efficiency as compared to‘no EC’, for example, ‘2nd layer EC’ may show that in >99.9% of the cases, the application layer packet loss rate may be kept below 0.1% at a cost of ~3% sacrifice on spectral efficiency. The main reason is that with layer 2 EC, repair packets may be used via on-demand re-transmission of EC PDUs, with no redundant repair packets as in AL-FEC.‘2nd layer EC + LA’ may further achieve more spectral efficiency with much higher robustness as compared to‘no EC.’ For example, aggressive threshold values, such as THH = THL = 20%, may be used to harvest higher spectral efficiency while providing robustness via re transmission of EC PDUs.

[0046] FIG. 3 illustrates the CDF of application layer spectral efficiency (SE), comparing‘no EC’,‘AL-FEC’ (with no LA), and‘AL-FEC + LA,’ where both AL-FEC and LA are switched on. LA may operate for various sample values of ‘threshold higher,’ denoted by THH, and ‘threshold lower,’ denoted by THL. To ease demonstration of the proposed scheme, simulations are performed for various sample values of a threshold where THH and THL are assigned to the same value. The MCS decrement offset ‘mcs delta offset decrement’ and increment offset

‘mcs delta offset increment’ may be as 1 and 0.1, respectively. The mean SE values corresponding to‘AL-FEC + LA’ are shown by dashed lines with as the corresponding CDF plots. Alternatively, the corresponding performance on the application layer packet loss rate and EC PDU loss rate are illustrated in FIG. 4 and FIG. 5, respectively. In cases of no LA, a fixed sample MCS setting with QPSK and coding rate = 0.59 may be used. The AL- FEC may be assumed to use 20% packet redundancy for the repair packets. The PLRs may be measured on EC PDUs over a one second interval, which may be the higher layer EC interval. The sample measurement trigger used may be periodic measurement reporting.‘Multiple user report timer’ may be set to 100 ms to ensure reception of all potential measurement reports from multiple UE.

[0047] FIG. 6 illustrates CDF of application layer spectral efficiency (SE) comparing‘no EC,’‘2nd Layer EC’ (with no LA) and‘2nd Layer EC + LA,’ where both Layer 2 EC and LA are switched on. Herein, LA may operate for various sample values of ‘threshold higher,’ denoted by THH, and ‘threshold lower,’ denoted by THL. To ease demonstration of the proposed scheme, simulations are performed for various sample values of a threshold, where THH and THL are assigned to same value. The MCS decrement offset ‘mcs delta offset decrement’ and increment offset

‘mcs delta offset increment’ may be configured to 1 and 0.1, respectively. The mean SE values corresponding to‘2nd Layer EC’ and‘2nd Layer EC + LA’ may be shown by dashed lines as the corresponding CDF plots. Alternatively, the corresponding performance on the application layer packet loss rate and EC PDU loss rate are illustrated in FIG. 7 and FIG. 8, respectively. The PLRs may be measured on EC PDUs over a one second interval which, in this example, is the higher layer EC interval. The sample measurement trigger used may be periodic measurement reporting.‘Multiple user report timer’ may be set to 100 ms to ensure reception of all potential measurement reports from multiple UE.

[0048] FIG. 9 illustrates a signaling diagram according to some embodiments. In step 901, NE 920, which may be similar to NE 1220 in FIG. 12, may apply at least one forward error encoding at a higher layer entity. In step 903, NE 920 may transmit at least one configuration and/or indication to measure packet loss rates to UE 930, which may be similar to UE 1210 in FIG. 12. The configuration or indication may be a radio resource configuration message and/or a higher layer entity message, where the higher layer entity may be a protocol entity for user plane, such as RLC. In step 905, NE 920 may transmit at least one configuration and/or indication to measure packet loss rates to UE 940, which may also be similar to UE 1210 in FIG. 12. The configuration or indication may be a radio resource configuration message or a higher layer entity message, where the higher layer entity may be a protocol entity for user plane, such as RLC.

[0049] In step 907, NE 920 may receive at least one measurement report associated with EC PDU PLR from UE 940. The measurement report may be received in a dedicated message, such as RRC message, or piggy-backed to existing UL control or user data channel messages to the network. In step 909, NE 920 may receive at least one measurement report associated with EC PDU PLR from UE 930. The measurement report may be received in a dedicated message, such as RRC message, or piggy-backed to existing UL control or user data channel messages to the network.

[0050] In step 911, NE 920 may process the at least one or two measurement reports and/or determine whether MCS modification is required. In step 913, NE 920 may perform cross-layer communication between a higher layer and a lower layer, where the higher layer and lower layer are not the same.

[0051] In step 915, NE 920 may modify at least one MCS in coordination with the higher layer EC. In step 917, NE 920 may perform cross-layer communication with UE 930 and/or UE 940 via at least one MAC layer MCS modification signal. In some embodiments, the higher layers may be in the network access or AL, and lower layers may be a MAC layer, where MCS modification is applied.

[0052] FIG. 10 illustrates a signaling diagram according to some embodiments. In step 1001, NE 1030, which may be similar to NE 1220 in FIG. 12, may apply at least one forward error encoding at a higher layer entity. In step 1003, NE 1030 may transmit at least one configuration and/or indication to measure packet loss rate to UE 1050, which may be similar to UE 1210 in FIG. 12. In step 1005, NE 1030 may tran it at least one configuration and/or indication to measure packet loss rate to UE 1060, which may be similar to UE 1210 in FIG. 12. In step 1007, NE 1030 may receive at least one measurement report on EC PDU PLR from UE 1060. In step 1009, NE 1030 may receive at least one measurement report on EC PDU PLR from UE 1050. In step 1011, NE 1030 may process the at least one or two measurement reports. In step 1013, NE 1030 may perform MCS modification via cross-layer communication between a higher layer and lower layer, which may not be the same. In step 1015, NE 1030 may perform MCS modification in coordination with the higher layer EC. In step 1017, NE 1030 may transmit at least one cross-layer MCS modification request to NE 1040, which may be similar to NE 1220 in FIG. 12, and in step 1019, NE 1030 may receive at least one cross-layer MCS modification response from NE 1040. In step 1021, NE 1040 may apply the at least one new MCS to at least one data transmission. In step 1023, NE 1030 may transmit at least one data transmission with the modified MCS to NE 1040, UE 1050, and/or UE 1060.

[0053] FIG. 11 illustrates an example of a method performed by a network entity, such as network entity 1220 illustrated in FIG. 12, according to certain embodiments. In step 1101, the NE may apply forward error coding at a higher protocol entity. In step 1103, the NE may transmit at least one indication to measure packet loss rates to a first user equipment, such as UE 1210 illustrated in FIG. 12, and at least one indication to measure packet loss rates to a second user equipment, such as UE 1210 illustrated in FIG. 12. In step 1105, the NE may receive at least one measurement report on EC PDU PLR from the first UE, and/or at least one measurement report on EC PDU PLR from the second UE. In step 1107, the NE may process the at least one or two measurement reports. In step 1109, the NE may perform cross-layer communication between a higher layer and a lower layer, where the higher layer and lower layer are not the same. In step 1111, the NE may modify at least one MCS in coordination with the higher layer EC. In step 1113, the NE may perform cross-layer communication with the first UE and/or the second UE via at least one MAC layer MCS modification signal.

[0054] FIG. 12 illustrates an example of a system according to certain embodiments. In one embodiment, a system may include multiple devices, such as, for example, user equipment 1210 and/or network entity 1220.

[0055] User equipment 1210 may include one or more of a mobile device, such as a mobile phone, smart phone, personal digital assistant (PDA), tablet, or portable media player, digital camera, pocket video camera, video game console, navigation unit, such as a global positioning system (GPS) device, desktop or laptop computer, single-location device, such as a sensor or smart meter, or any combination thereof.

[0056] Network entity 1220 may be one or more of: a base station, such as an evolved node B (eNB) or 5G or New Radio node B (gNB), a serving gateway, a server, and/or any other access node or combination thereof. Network entity 1220 may also be similar to user equipment 1210. Furthermore, network entity 1220 and/or user equipment 1210 may be one or more of a citizens broadband radio service device (CBSD).

[0057] In addition, in some embodiments, functionality of the network entity 1220 and/or UE 1210 may be implemented by other network nodes, such as a wireless relay node. For example, functionalities of UE 1210 may be performed by a mobile termination (MT) component of the IAB node.

[0058] One or more of these devices may include at least one processor, respectively indicated as 1211 and 1221. Processors 1211 and 1221 may be embodied by any computational or data processing device, such as a central processing unit (CPU), application specific integrated circuit (ASIC), or comparable device. The processors may be implemented as a single controller, or a plurality of controllers or processors.

[0059] At least one memory may be provided in one or more of devices indicated at 1212 and 1222. The memory may be fixed or removable. The memory may include computer program instructions or computer code contained therein. Memories 1212 and 1222 may independently be any suitable storage device, such as a non-transitory computer-readable medium. A hard disk drive (HDD), random access memory (RAM), flash memory, or other suitable memory may be used. The memories may be combined on a single integrated circuit as the processor, or may be separate from the one or more processors. Furthermore, the computer program instructions stored in the memory and which may be processed by the processors may be any suitable form of computer program code, for example, a compiled or interpreted computer program written in any suitable programming language. Memory may be removable or non-removable.

[0060] Processors 1211 and 1221 and memories 1212 and 1222 or a subset thereof, may be configured to provide means corresponding to the various blocks of FIGS. 1-11. Although not shown, the devices may also include positioning hardware, such as GPS or micro electrical mechanical system (MEMS) hardware, which may be used to determine a location of the device. Other sensors are also permitted and may be included to determine location, elevation, orientation, and so forth, such as barometers, compasses, and the like.

[0061] As shown in FIG. 12, transceivers 1213 and 1223 may be provided, and one or more devices may also include at least one antenna, respectively illustrated as 1214 and 1224. The device may have many antennas, such as an array of antennas configured for multiple input multiple output (MIMO) communications, or multiple antennas for multiple radio access technologies. Other configurations of these devices, for example, may be provided. Transceivers 1213 and 1223 may be a transmitter, a receiver, or both a transmitter and a receiver, or a unit or device that may be configured both for transmission and reception.

[0062] The memory and the computer program instructions may be configured, with the processor for the particular device, to cause a hardware apparatus such as user equipment to perform any of the processes described below (see, for example, FIGS. 1-11). Therefore, in certain embodiments, a non-transitory computer-readable medium may be encoded with computer instructions that, when executed in hardware, perform a process such as one of the processes described herein. Alternatively, certain embodiments may be performed entirely in hardware.

[0063] In certain embodiments, an apparatus may include circuitry configured to perform any of the processes or functions illustrated in FIGS. 1-11. For example, circuitry may be hardware-only circuit implementations, such as analog and/or digital circuitry. In another example, circuitry may be a combination of hardware circuits and software, such as a combination of analog and/or digital hardware circuit(s) with software or firmware, and/or any portions of hardware processor(s) with software (including digital signal processor(s)), software, and at least one memory that work together to cause an apparatus to perform various processes or functions. In yet another example, circuitry may be hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that include software, such as firmware for operation. Software in circuitry may not be present when it is not needed for the operation of the hardware.

[0064] The features, structures, or characteristics of certain embodiments described throughout this specification maybe combined in any suitable manner in one or more embodiments. For example, the usage of the phrases“certain embodiments,”“some embodiments,”“other embodiments,” or other similar language, throughout this specification refers to the fact that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present invention. Thus, appearance of the phrases“in certain embodiments,”“in some embodiments,”“in other embodiments,” or other similar language, throughout this specification does not necessarily refer to the same group of embodiments, and the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0065] One having ordinary skill in the art will readily understand that certain embodiments discussed above may be practiced with steps in a different order, and/or with hardware elements in configurations which are different than those which are disclosed. Therefore, it would be apparent to those of skill in the art that certain modifications, variations, and alternative constructions would be apparent, while remaining within the spirit and scope of the invention. In order to determine the metes and bounds of the invention, therefore, reference should be made to the appended claims.

[0066] Partial Glossary

[0067] 3 GPP 3rd Generation Partnership Project

[0068] 5G 5th Generation

[0069] 5GPPP 5G Infrastructure Public Private Partnership

[0070] ACK Acknowledgement

[0071] AL Application Layer

[0072] AL-FEC Application Layer Forward Error Correction

[0073] ARQ Automatic Repeat Request

[0074] CQI Channel Quality Indicator

[0075] EC Error Correction

[0076] eMBB Enhanced Mobile Broadband

[0077] eNB Evolved Node B

[0078] EPC Evolved Packet Core

[0079] FEC Forward Error Correction

[0080] gNB Next Generation eNB

[0081] GPS Global Positioning System

[0082] HARQ Hybrid Automatic Repeat Request

[0083] LA Link Adaptation [0084] LTE Long-Term Evolution

[0085] MAC Medium Access Control

[0086] MCS Modulation and Coding Scheme

[0087] MME Mobility Management Entity

[0088] MTC Machine-Type Communications

[0089] NACK No Acknowledgement

[0090] NR New Radio

[0091] PDCCH Physical Downlink Control Channel

[0092] PDCP Packet Data Convergence Protocol

[0093] PDSCH Physical Downlink Shared Channel

[0094] PDU Protocol Data Unit

[0095] PLR Packet Loss Rate

[0096] PRB Physical Resource Block

[0097] PUCCH Physical Uplink Control Channel

[0098] PUSCH Physical Uplink Shared Channel

[0099] PTM Point-to-Multipoint

[0100] RAN Radio Access Network

[0101] RLC Radio Link Control

[0102] SDU Service Data Unit

[0103] SE Spectral Efficiency

[0104] SN Sequence Number

[0105] UE User Equipment

[0106] URLLC Ultra-Reliable and Low-Latency Communication [0107] WLAN Wireless Local Area Network