Patent Description:
Document <CIT>, document <CIT>, and document <NPL> are documents of the prior art in the technical field in question.

In wireless communications, e.g., Millimeter Wave (mmW) wireless communication, base stations and UEs can transmit and/or receive a plurality of signals in order to facilitate communication between each other. Such signaling may increase the overhead of the communication system. If the signaling results in an increase in overhead, then any power savings or reduction in latency may be reduced or negated. In order to reduce the overhead as a result of this signaling, wireless communication systems can use Non-Orthogonal Multiple Access (NOMA) communication. Compared to transmissions such as Orthogonal Multiple Access (OMA), NOMA transmissions can reduce signaling overhead in a variety of ways, such as reducing signaling for resource allocation. By utilizing the concepts of grant-based and grant-free NOMA, the overhead of a wireless communication system can be reduced.

The present disclosure relates to methods and devices for communicating based on improved signaling of resources allocated for NOMA. A base station can transmit an indication of allocated resources in time and frequency to a UE for NOMA communication with the UE. The indication of resources can comprise a set of NOMA resource units (NA-RUs). The UE can then transmit uplink NOMA communication to the base station based on the indicated NA-RUs. The indication of the resources can also be based on a NOMA raster of candidate locations for the NA-RUs. Additionally, the set of NA-RUs can be indicated based on a predefined function. The indication of the resources can also be based on a bitmap for the set of the NA-RUs.

Furthermore, the indication of the resources can comprise a starting location of the set of the NA-RUs and a number of the NA-RUs comprised in the set. The indication can also comprise a starting location of the set of the NA-RUs, as well as an ending location of the set of the NA-RUs. The set of the NA-RUs can comprise a number of NA-RUs that are contiguous in time and/or frequency. The set of the NA-RUs can be interlaced in time and/or frequency within a superset of NA-RUs. In addition, the uplink NOMA communication may be transmitted to the base station without an uplink grant. In this sense, the uplink NOMA communication can be grant-free NOMA communication or configured grant NOMA communication.

The base station can also transmit downlink control information (DCI) to the UE for NOMA communication with the UE. The DCI can be scrambled with a NOMA group Radio Network Temporary Identifier (RNTI). The DCI can also comprise NOMA transmission parameters indicated by a modulation and coding scheme (MCS) table. The UE can then transmit uplink NOMA communication to the base station based on the DCI. The DCI may be received based on a group common control channel or Remaining Minimum System Information (RMSI) for a common resource allocation. The DCI can also comprise a cyclic redundancy check (CRC) that is scrambled by the NOMA group RNTI. Further, the DCI can comprise one or more NOMA transmission parameters indicated by the MCS table. The one or more NOMA transmission parameters can comprise a spreading factor for a NOMA transmission, a seed of scrambling code for the NOMA transmission, and/or one or more layers for multiple branch transmission of the NOMA transmission. The DCI can also comprise a multiple stage DCI scrambled by the NOMA group RNTI.

The base station can also transmit, and the UE can receive, a compressed uplink grant. The compressed uplink grant can be based on a table of NOMA transport formats. The compressed uplink grant can indicate an index for a transport format from among multiple transport formats for the uplink NOMA communication. In addition, the compressed uplink grant can comprise an index of at least one transport format that can be received through Radio Resource Control (RRC) signaling.

Aspects of the present invention are set out in the accompanying claims. In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided for wireless communication at a UE. The apparatus can receive an indication of resources in time and frequency from a base station allocated for NOMA communication with the base station. The indication of resources can comprise a set of NA-RUs. Moreover, the apparatus can transmit uplink NOMA communication to the base station based on the indication of resources received from the base station.

In another aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided for wireless communication at a base station. The apparatus can transmit an indication of resources in time and frequency to a UE allocated for NOMA communication with the UE, wherein the indication of resources comprises a set of NA-RUs. Furthermore, the apparatus can receive uplink NOMA communication from the UE based on the indication of resources transmitted to the UE.

In a further aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided for wireless communication at a UE. The apparatus can receive DCI from a base station allocated for NOMA communication with the base station. The DCI can be scrambled with a NOMA group RNTI. The DCI can also comprise NOMA transmission parameters indicated by an MCS table. The apparatus can also transmit uplink NOMA communication to the base station based on the DCI received from the base station. In addition, the apparatus can receive a compressed uplink grant.

In a further aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided for wireless communication at a base station. The apparatus can transmit DCI to a UE allocated for NOMA communication with the UE. The DCI can be scrambled with a NOMA group RNTI. The DCI can also comprise NOMA transmission parameters indicated by an MCS table. The apparatus can also receive uplink NOMA communication from the UE based on the DCI transmitted to the UE. Moreover, the apparatus can transmit a compressed uplink grant.

Accordingly, in one or more examples, the functions described may be implemented in hardware, software, or any combination thereof.

The wireless communications system (also referred to as a wireless wide area network (WWAN)) includes base stations <NUM>, UEs <NUM>, an Evolved Packet Core (EPC) <NUM>, and a <NUM> Core (5GC) <NUM>.

The base stations <NUM> configured for <NUM> LTE (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN)) may interface with the EPC <NUM> through backhaul links <NUM> (e.g., S1 interface). The base stations <NUM> configured for <NUM> NR (collectively referred to as Next Generation RAN (NG-RAN)) may interface with 5GC <NUM> through backhaul links <NUM>. The base stations <NUM> may communicate directly or indirectly (e.g., through the EPC <NUM> or 5GC <NUM>) with each other over backhaul links <NUM> (e.g., X2 interface).

The base stations <NUM> / UEs <NUM> may use spectrum up to YMHz (e.g., <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, etc. MHz) bandwidth per carrier allocated in a carrier aggregation of up to a total of Yx MHz (x component carriers) used for transmission in each direction.

The 5GC <NUM> may include a Access and Mobility Management Function (AMF) <NUM>, other AMFs <NUM>, a Session Management Function (SMF) <NUM>, and a User Plane Function (UPF) <NUM>. The AMF <NUM> is the control node that processes the signaling between the UEs <NUM> and the 5GC <NUM>.

The base station <NUM> provides an access point to the EPC <NUM> or 5GC <NUM> for a UE <NUM>.

Referring again to <FIG>, in certain aspects, base station <NUM>/<NUM> may include a transmission component <NUM> configured to transmit an indication of resources in time and frequency to UE allocated for NOMA communication. Transmission component <NUM> can also be configured to receive uplink NOMA communication from UE based on indication of resources. Transmission component <NUM> can also be configured to transmit DCI or semi-static uplink resource grant to UE allocated for NOMA communication. Further, transmission component <NUM> can be configured to transmit compressed uplink resource grant by RRC signaling or compact DCI by PDCCH. Transmission component <NUM> can also be configured to receive uplink NOMA communication from UE based on DCI or semi-static uplink resource grant. In certain aspects, UE <NUM> may include a reception component <NUM> configured to receive an indication of resources in time and frequency from base station allocated for NOMA communication. Reception component <NUM> can also be configured to transmit uplink NOMA communication to base station based on indication of resources. Reception component <NUM> can also be configured to receive DCI or semi-static uplink resource grant from base station allocated for NOMA communication. Additionally, reception component <NUM> can be configured to receive compressed uplink resource grant by RRC signaling or compact DCI by PDCCH. Reception component <NUM> can also be configured to transmit uplink NOMA communication to base station based on DCI or semi-static uplink resource grant.

The subcarrier spacing may be equal to <NUM>µ * <NUM> kKz, where µ is the numerology <NUM> to <NUM>.

<FIG> is a diagram <NUM> illustrating a base station <NUM> in communication with a UE <NUM>. Referring to <FIG>, the base station <NUM> may transmit a beamformed signal to the UE <NUM> in one or more of the directions 402a, 402b, 402c, 402d, 402e, 402f, <NUM>, <NUM>. The UE <NUM> may receive the beamformed signal from the base station <NUM> in one or more receive directions 404a, 404b, 404c, 404d. The UE <NUM> may also transmit a beamformed signal to the base station <NUM> in one or more of the directions 404a-404d. The base station <NUM> may receive the beamformed signal from the UE <NUM> in one or more of the receive directions 402a-<NUM>.

In wireless communications, e.g., mmW wireless communication, base stations and UEs can transmit and/or receive a plurality of signals in order to facilitate communication between each other. Such signaling may require an increase in the overhead of the communication system. If the signaling results in an increase in overhead, then any power savings or reduction in latency may be reduced or negated. In order to reduce the overhead as a result of this signaling, wireless communication systems can use NOMA communication. NOMA communication can apply to different use cases. As an example, NOMA communication can focus on uplink transmissions with a base station as a receiver. In this example, the base station can be considered an advanced receiver with interference cancellation capabilities. A base station may comprise a gNB, for example. NOMA transmissions may include one more payload.

As indicated above, NOMA transmission can differ from traditional OMA transmission. In OMA transmissions, transmissions from different UEs are orthogonal to each other in time and/or frequency resources. Thus, the base station is able to identify the UE sending the transmission based on the time and/or frequency resources on which the transmission is received. In NOMA transmissions, different UEs share the time and frequency resources, e.g., data transmissions from different UEs are not orthogonal. NOMA transmissions may comprise a first data transmission and/or retransmissions. Such NOMA transmissions from UEs may be referred to as non-orthogonal uplink transmissions.

NOMA transmission may comprise a small payload. NOMA transmissions may enable possible savings of systems overhead, power reduction, and latency reduction. NOMA may be used in connection with massive machine-type communications (mMTC), ultra-reliable low-latency communications (URLLC), and enhanced mobile broadband (eMBB), e.g., for communication with small payloads. The aspects presented herein can be applicable to grant-based and/or grant-free transmissions. In these instances, NOMA transmissions can be referred to as grant-based NOMA and grant-free NOMA.

NOMA deployments may help to reduce signaling overhead. Signaling overhead reduction may be associated with power savings and latency reduction. Signaling in NOMA transmissions may include control channel signaling, e.g., PDCCH, which can carry the downlink and uplink scheduling information.

Compared to grant-based NOMA transmissions, grant-free or configured grant NOMA transmissions can save the signaling overhead for a scheduling request (SR) and dynamic DCI. Grant-based transmissions can use an uplink grant or SR, while grant-free transmissions may be sent without a specific uplink grant from the base station and/or SR from the UE. For grant-based NOMA, the NOMA data transmissions on the uplink may be scheduled by an uplink grant. In some aspects, the uplink grant can be transmitted on the PDCCH with DCI. Compared to grant-based OMA transmission, grant-based and grant-free NOMA can help to save the signaling overhead associated with resource allocation indication. In NOMA transmissions, even in grant-based NOMA transmissions, the NOMA UE can share the time and frequency resources with other NOMA UEs. In some aspects, a resource allocation indication can be common to multiple NOMA UEs. As will be discussed further herein, signaling overhead reduction schemes can be used with for grant-based and grant-free NOMA transmissions.

There are several ways that NOMA transmissions according to the present disclosure can reduce signaling overhead. For example, some NOMA transmissions can allow for a more efficient way to allocate resources for a first NOMA transmission, as well as any subsequent re-transmission. Shared time and/or frequency resources, e.g., for a group of NOMA UEs, can be partitioned into NOMA-specific resource units (NA-RUs). The NA-RUs may be indexed, and the indexes may be used to indicate NOMA resources to NOMA UEs.

<FIG> display examples of shared time and/or frequency resources <NUM>, <NUM>, and <NUM>, respectively, being partitioned into NA-RUs and indexed. In one example, as shown in <FIG>, <FIG> contiguous subcarriers or physical RB (PRB) pairs can comprise an NA-RU. In another example, as shown in <FIG>, six interlaced subcarriers or PRB pairs can comprise an NA-RU. <FIG> illustrates an example of interlacing in frequency. In another example, as shown in <FIG>, six cross interlaced subcarriers or PRB pairs can comprise an NA-RU. <FIG> illustrates an example of interlacing in both time and frequency. As mentioned herein, these PRB pairs can be contiguous or interlaced in time and/or frequency. For example, six PRB pairs can be in a single slot along the frequency spectrum. In other examples, a different number of PRB pairs may form an NA-RU.

As mentioned herein, NOMA transmissions can consider the signaling overhead impact on the wireless communication system. The use of NA-RUs to indicate NOMA resources can reduce the amount of overhead used to indicate NOMA resource allocation. By compacting the way in which resource units are indicated to the UE may reduce the amount of data that DCI use to convey the allocation information. In addition, multiple access for NOMA transmissions can cross correlate time and frequency resources, such that each of these resources can alternate with the other and/or be a contiguous block of resources. Accordingly, the time and/or frequency resources can be indexed as contiguous or interlaced.

<FIG> displays an example of resource allocation <NUM>. Specifically, <FIG> shows a NOMA-specific raster for the candidate locations of NA-RUs. For example, NOMA resource allocation may be indicated based on a NOMA-specific raster for candidate locations of NA-RUs. A raster can limit the NOMA-specific frequencies to be within a range of RBs. Additionally, a raster can enable the NOMA transmissions to focus on frequency as well as time. The raster may provide parameters that are defined with respect to a signal. In <FIG>, {K<NUM>, K<NUM>, L} are defined with respect to one or more synchronization signal blocks (SSBs). For example, in <FIG>, K<NUM> indicates a frequency offset from a first SSB, K<NUM> indicates a frequency offset from a second SSB, and L indicates a period of time. {K<NUM>, K<NUM>, L} may be configurable parameters, which may be a function of system bandwidth, the size of NR-RU, and the associated subcarrier spacing (SCS). The base station may indicate a raster to the UE for NOMA communication, and the UE may use the raster to determine NA-RUs for transmitting NOMA communication to the base station.

In some instances, NOMA transmissions may target small payloads transmissions. However, other instances can allow for large payload transmissions. When using a raster, some NOMA transmissions can use a wide load SSB transmission, e.g., where the SSB transmission utilizes a wide bandwidth. Further, the amount of RBs used with the raster can be configured, e.g., based on the NOMA resource allocation. In some aspects, the raster can be centered around a middle frequency. For instance, the raster can comprise an even number of RBs centered around the center RB.

In another example, a NOMA resource allocation may be indicated based on a predefined function. For example, a set of NA-RUs may be mapped to a time and frequency grid with respect to an SSB based on a predefined function. The function may specify any of a center frequency of the NA-RUs, a subcarrier spacing, a number of PRBs within each NA-RU, etc..

<FIG> displays an example of resource allocation <NUM>. In the example in <FIG>, {f<NUM>, f<NUM>, L<NUM>, L<NUM>} may be configurable parameters, which are a function of system bandwidth, the size of NR-RU, and SCS. For example, f<NUM> may provide a center frequency for a first NA-RU and L<NUM> may indicate time resources for the first NA-RU. Similarly, f<NUM> may indicate a center frequency for a second NA-RU, and L<NUM> may indicate time resources for the second NA-RU. The parameters may form a hopping pattern. The hopping pattern of {f<NUM>, f<NUM>, L<NUM>, L<NUM>} can be described by a math function or sequence, such as hash function or pseudo-noise (PN) sequence. In some aspects, the NOMA transmissions can define a related offset for the SSB transmission. This offset can be a time variant, as well as based on diversity gain. In this sense, NOMA transmissions can predefine the frequency offset. For example, NOMA transmissions use an index into the Hash function, which provides a location for the NOMA resources relative to the SSB. In some aspects, the SSB transmission can be a starting point for determining the NA-RUs for NOMA communication by the UE.

In another example, a NOMA resource allocation may be indicated based on bitmapping. In some aspects, bitmapping may be used to index the NA-RUs. The bitmapping can help to control a channel element. In one aspect of the present disclosure, the DCI can carry the bitmap or bitmap index. <FIG> displays an example of resource allocation <NUM>. <FIG> illustrates an example of two NA-RU bitmaps. In some aspects utilizing a bitmap, each bit can have a certain value. For a given bitmap, "<NUM>" may indicate that the corresponding NA-RU is not allocated to NOMA UE. Such resources might be assigned to an OMA UE. In the bitmap, "<NUM>" may indicate that the corresponding NA-RU is allocated to a group of NOMA UE. Thus, the bitmap may provide an indication showing the UE which NA-RUs are allocated to the group of NOMA UEs and which NA-RUs are allocated to the group of NOMA UEs. The bitmap can be time variant when the NA-RU resource allocation is dynamic. As mentioned above, each NA-RU can be contiguous in a slot, and the UEs can share time and/or frequency locations. All the UEs can monitor the transmission space. Additionally, different UEs can schedule different NA-RU index numbers. For instance, there can be simultaneous uplink NOMA transmissions going to different NA-RUs, so bitmapping can help to allocate these simultaneous transmissions. In some aspects, bitmapping can help to allocate multiple, parallel NOMA transmissions. As such, bitmapping may not require the transmissions to be contiguous.

<FIG> displays an example of resource allocation <NUM>. <FIG> displays another example in which a NOMA resource allocation may be indicated based on a starting location and/or a number of NA-RUs. In some aspects, the starting location can be an index or number. This option can be a more compact way to indicate the NOMA resource allocation. As displayed in <FIG>, the base station may signal a starting location of x for the NA-RU(s) and a number Y of consecutive NA-RUs. In this example, Y NA-RUs can be allocated to the group of NOMA UEs through the indication. Thus, the UE may determine that the index of the allocated NA-RU corresponds to {x, x+<NUM>,. , x+Y-<NUM>}.

<FIG> displays an example of resource allocation <NUM>. <FIG> displays an example wherein the NOMA resource allocation can be indicated based on a starting location and/or an ending location. Like the previous example, this option can also be a compact way to indicate the NOMA resource allocation. As displayed in <FIG>, the base station may signal a starting location of x for the NA-RU(s) and an ending location of z for the NA-RU(s). Thus, (z-x+<NUM>) NA-RUs can be allocated to a group of NOMA UEs through the indication. Based on the indication, the UE may determine that index of the allocated NA-RU is given by {x, x+<NUM>,. The two options displayed in <FIG> and <FIG> can be used interchangeably with one another, as they both utilize starting locations. Accordingly, different options can be utilized to indicate the resource allocation for NOMA transmissions. For instance, the PRB pairs can be grouped on a grid, as well as index the PRB pairs into an NA-RU number.

In some aspects, NOMA transmission herein can include additional communication methods. More specifically, NOMA transmissions herein may include random access channel (RACH) communication method. One example of NOMA communication may be a two-step RACH. Further, a communication messages between multiple UEs may use similar RACH resources. For example, a first message between multiple UEs may include a preamble and data, such that the multiple UEs are using the same random access resources. In some aspects, NOMA communication may utilize a number of different channels, such as a PUSCH. Additionally, NOMA communication may utilize HARQ, such as in response to certain channel communication, e.g., PUSCH.

<FIG> is a diagram <NUM> illustrating transmissions between base station <NUM> and UE <NUM>. For instance, base station <NUM> can, at <NUM>, transmit an indication of resources in time and frequency <NUM> to UE <NUM> allocated for NOMA communication based on NA-RUs. The indication of resources can comprise a set of NA-RUs. At <NUM>, UE <NUM> receives the indication of resources in time and frequency from base station <NUM>. The indication of the resources can be based on a NOMA raster of candidate locations for the NA-RUs, e.g., as described in connection with the example in <FIG>. Additionally, the set of NA-RUs can be mapped to the time frequency resource grid with respect to the SSB based on a predefined function, e.g., as described in connection with the example of <FIG>. The predefined function may specify the center frequency of NA-RUs, the subcarrier spacing used, or the number of PRBs within each NA-RU.

Moreover, the indication of resources can be based on a bitmap for the set of the NA-RUs, as described in connection with the example in <FIG>. The indication can also comprise a starting location of the set of the NA-RUs and/or a number of the NA-RUs comprised in the set, as described in connection with the example in <FIG>. Further, the indication can comprise a starting location of the set of the NA-RUs and/or an ending location of the set of the NA-RUs, as described in connection with the example in <FIG>. The set of the NA-RUs can comprise a number of NA-RUs that are contiguous in time or frequency, as illustrated in the example in <FIG>. The set of the NA-RUs can be interlaced in time and/or frequency within a resource grid, as illustrated in the examples in <FIG>. The resource grid may span the entire system bandwidth in frequency and the entire slot in time, and the slot index for NR-RU can be semi-static or dynamically configured. Also, the uplink NOMA communication can be received from the UE, and multiple UEs may share the same NR-RUs in time and frequency domain.

At <NUM>, UE <NUM> can also transmit uplink NOMA communication <NUM> to base station <NUM> based on the indication of resources. Finally, at <NUM>, base station <NUM> can receive uplink NOMA communication from the UE based on the indication of resources.

<FIG> is a flowchart <NUM> of a method of wireless communication. The method may be performed by a UE (e.g., UE <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, apparatus <NUM>; the processing system <NUM>, which may include memory <NUM> and which may be the entire UE <NUM> or a component of the UE <NUM>, such as the TX processor <NUM>, the RX processor <NUM>, and/or the controller/processor <NUM>) communicating with a base station (e.g., base station <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, apparatus <NUM>). Optional aspects are illustrated with a dashed line. The methods described herein can provide a number of benefits, such as improving power savings and/or resource utilization.

At <NUM>, the UE can receive an indication of resources in time and/or frequency from a base station allocated for NOMA communication with the UE. For example, reception component <NUM> of apparatus <NUM> may receive an indication of resources in time and/or frequency from a base station allocated for NOMA communication. The indication of resources can comprise a set of NA-RUs. As mentioned above, the indication of the resources can be based on a NOMA raster of candidate locations for the NA-RUs, as described in connection with the example in <FIG>. The set of NA-RUs can also be mapped to the time frequency resource grid with respect to the SSB based on a predefined function, as described in connection with the example in <FIG>. The function may specify the center frequency of NA-RUs, the subcarrier spacing used, and/or the number of PRBs within each NA-RU.

Additionally, the indication of resources can be based on a bitmap for the set of the NA-RUs, as described in connection with the example in <FIG>. The indication can also comprise a starting location of the set of the NA-RUs and/or a number of the NA-RUs comprised in the set, as described in connection with the example in <FIG>. Moreover, the indication can comprise a starting location of the set of the NA-RUs and/or an ending location of the set of the NA-RUs, as described in connection with the example in <FIG>. The set of the NA-RUs can comprise a number of NA-RUs that are contiguous in time or frequency, as illustrated in the example in <FIG>. The set of the NA-RUs can be interlaced in time and/or frequency within a resource grid, as illustrated in the examples in <FIG>. The resource grid may span the entire system bandwidth in frequency and the entire slot in time. A slot index for NR-RU can be semi-static or dynamically configured by the base station. Also, the uplink NOMA communication can be received from the UE, and multiple UEs may share the same NA-RUs in time and frequency domain.

In addition, at <NUM>, the UE can transmit uplink NOMA communication to the base station based on the indication of resources, e.g., using at least one of the indicated NA-RUs allocated to a group of NOMA UEs including the UE. For example, transmission component <NUM> of apparatus <NUM> may transmit uplink NOMA communication to the base station based on the indication of resources.

<FIG> is a conceptual data flow diagram <NUM> illustrating the data flow between different means/components in an exemplary apparatus <NUM>. The apparatus may be a UE or a component of a UE. The apparatus includes a reception component <NUM> that is configured to receive downlink communication from base station <NUM> and a transmission component <NUM> configured to transmit uplink communication to the base station <NUM>. The apparatus further includes a NOMA indication component <NUM> that is configured to receive, e.g., via reception component <NUM>, an indication of resources in time and frequency from a base station allocated for NOMA communication with the UE. The indication of resources can comprise a set of NA-RUs. The apparatus can also include a NOMA transmission component <NUM> that is configured to transmit uplink NOMA communication to the base station based on the indication of resources.

<FIG> is a diagram <NUM> illustrating an example of a hardware implementation for an apparatus <NUM>' employing a processing system <NUM>. The processing system <NUM> may be implemented with a bus architecture, represented generally by the bus <NUM>. The bus <NUM> may include any number of interconnecting buses and bridges depending on the specific application of the processing system <NUM> and the overall design constraints. The bus <NUM> links together various circuits including one or more processors and/or hardware components, represented by the processor <NUM>, the components <NUM>, <NUM>, <NUM>, <NUM>, and the computer-readable medium / memory <NUM>. The bus <NUM> may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, will not be described any further.

The processing system <NUM> may be coupled to a transceiver <NUM>. The transceiver <NUM> is coupled to one or more antennas <NUM>. The transceiver <NUM> provides a means for communicating with various other apparatus over a transmission medium. The transceiver <NUM> receives a signal from the one or more antennas <NUM>, extracts information from the received signal, and provides the extracted information to the processing system <NUM>, specifically the reception component <NUM>. In addition, the transceiver <NUM> receives information from the processing system <NUM>, specifically the transmission component <NUM>, and based on the received information, generates a signal to be applied to the one or more antennas <NUM>. The processing system <NUM> includes a processor <NUM> coupled to a computer-readable medium / memory <NUM>. The processor <NUM> is responsible for general processing, including the execution of software stored on the computer-readable medium / memory <NUM>. The software, when executed by the processor <NUM>, causes the processing system <NUM> to perform the various functions described supra for any particular apparatus. The computer-readable medium / memory <NUM> may also be used for storing data that is manipulated by the processor <NUM> when executing software. The processing system <NUM> further includes at least one of the components <NUM>, <NUM>, <NUM>, <NUM>. The components may be software components running in the processor <NUM>, resident/stored in the computer readable medium / memory <NUM>, one or more hardware components coupled to the processor <NUM>, or some combination thereof. The processing system <NUM> may be a component of the UE <NUM> and may include the memory <NUM> and/or at least one of the TX processor <NUM>, the RX processor <NUM>, and the controller/processor <NUM>. Alternately, the processing system <NUM> may comprise the entire UE, e.g., UE <NUM>.

In one configuration, the apparatus <NUM>/<NUM>' for wireless communication includes means for receiving an indication of resources in time and frequency from a base station allocated for NOMA communication with the base station. The indication of resources can comprise a set of NA-RUs. The apparatus can also include means for transmitting uplink NOMA communication to the base station based on the indication of resources received from the base station.

<FIG> is a flowchart <NUM> of a method of wireless communication. The method may be performed by a base station (e.g., base station <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, apparatus <NUM>; the processing system <NUM>, which may include memory <NUM> and which may be the entire base station <NUM> or a component of a base station, such as the TX processor <NUM>, the RX processor <NUM>, and/or the controller/processor <NUM>) communicating with a UE (e.g., UE <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, apparatus <NUM>). Optional aspects are illustrated with a dashed line. The methods described herein can provide a number of benefits, such as improving power savings and/or resource utilization.

At <NUM>, the base station can transmit an indication of resources in time and frequency to a UE allocated for NOMA communication with the base station. For example, transmission component <NUM> of apparatus <NUM> may transmit an indication of resources in time and frequency to a UE allocated for NOMA communication. The indication of resources can comprise a set of NA-RUs. As mentioned above, the indication of the resources can be based on a NOMA raster of candidate locations for the NA-RUs, as described in connection with the example in <FIG>. The set of NA-RUs can also be mapped to the time frequency resource grid with respect to the SSB based on a predefined function, as described in connection with the example in <FIG>. The function may specify the center frequency of NA-RUs, the subcarrier spacing used, and/or the number of PRBs within each NA-RU.

Further, the indication of resources can be based on a bitmap for the set of the NA-RUs, as described in connection with the example in <FIG>. The indication can also comprise a starting location of the set of the NA-RUs and/or a number of the NA-RUs comprised in the set, as described in connection with the example in <FIG>. Also, the indication can comprise a starting location of the set of the NA-RUs and an ending location of the set of the NA-RUs, as described in connection with the example in <FIG>. The set of the NA-RUs can comprise a number of NA-RUs that are contiguous in time or frequency, as illustrated in the example in <FIG>. The set of the NA-RUs can be interlaced in time or frequency within a resource grid, as illustrated in the examples in <FIG>. The resource grid may span the entire system bandwidth in frequency and the entire slot in time, and the slot index for NR-RU can be semi-static or dynamically configured. The uplink NOMA communication can be received from the UE, and multiple UEs share the same NR-RUs in time and frequency domain.

Finally, at <NUM>, the base station can receive uplink NOMA communication from the UE based on the indication of resources. For example, reception component <NUM> of apparatus <NUM> may receive uplink NOMA communication from the UE based on the indication of resources.

<FIG> is a conceptual data flow diagram <NUM> illustrating the data flow between different means/components in an exemplary apparatus <NUM>. The apparatus may be a base station or a component of a base station. The apparatus includes a transmission component <NUM> that is configured to transmit an indication of resources to the UE <NUM>. The apparatus further includes NOMA transmission component <NUM> that is configured to transmit, e.g., via transmission component <NUM>, an indication of resources in time and frequency to UE <NUM> allocated for NOMA communication with the base station. The indication of resources can comprise a set of NA-RUs. The apparatus can also include a reception component <NUM> that is configured to receive uplink communication from UE <NUM>. The apparatus can further include NOMA indication component <NUM> that is configured to receive, e.g., via reception component <NUM> uplink NOMA communication from the UE based on the indication of resources.

The processing system <NUM> may be coupled to a transceiver <NUM>. The transceiver <NUM> is coupled to one or more antennas <NUM>. The transceiver <NUM> provides a means for communicating with various other apparatus over a transmission medium. The transceiver <NUM> receives a signal from the one or more antennas <NUM>, extracts information from the received signal, and provides the extracted information to the processing system <NUM>, specifically the reception component <NUM>. In addition, the transceiver <NUM> receives information from the processing system <NUM>, specifically the transmission component <NUM>, and based on the received information, generates a signal to be applied to the one or more antennas <NUM>. The processing system <NUM> includes a processor <NUM> coupled to a computer-readable medium / memory <NUM>. The processor <NUM> is responsible for general processing, including the execution of software stored on the computer-readable medium / memory <NUM>. The software, when executed by the processor <NUM>, causes the processing system <NUM> to perform the various functions described supra for any particular apparatus. The computer-readable medium / memory <NUM> may also be used for storing data that is manipulated by the processor <NUM> when executing software. The processing system <NUM> further includes at least one of the components <NUM>, <NUM>, <NUM>, <NUM>. The components may be software components running in the processor <NUM>, resident/stored in the computer readable medium / memory <NUM>, one or more hardware components coupled to the processor <NUM>, or some combination thereof. The processing system <NUM> may be a component of the base station <NUM> and may include the memory <NUM> and/or at least one of the TX processor <NUM>, the RX processor <NUM>, and the controller/processor <NUM>. Alternately, the processing system <NUM> may comprise the entire base station, e.g., base station <NUM>.

In one configuration, the apparatus <NUM>/<NUM>' for wireless communication includes means for transmitting an indication of resources in time and frequency to a UE allocated for NOMA communication with the UE. The indication of resources can comprise a set of NA-RUs. The apparatus can also include means for receiving uplink NOMA communication from the UE based on the indication of resources transmitted to the UE.

In addition to, or alternatively to, the aspects described in connection with <FIG>,the present disclosure may reduce signaling overhead by compacting the DCI for NOMA communication and/or by utilizing a compressed form of configured grant for NOMA communication. In some aspects, a configured grant transmission can use an RRC configuration rather than in dynamic DCI in the PDCCH.

Additionally, a group RNTI for a group of NOMA UEs can be introduced. Thus, the RNTI may not be UE-specific, but rather group-specific and common to all NOMA UEs within a group. The group of NOMA UEs may share the same NA-RUs. Some aspects can also use a group RNTI to scramble or mask part of the CRC. As mentioned herein, NOMA transmissions can share time and frequency resources. Along these lines, most NOMA transmission schemes can share a common feature. For example, when using a scrambling based NOMA transmission, the scrambling length can be the same for all NOMA transmissions. These common features of NOMA transmissions can provide a basis for the compact signaling.

<FIG> displays an example of a signaling scheme <NUM>. <FIG> displays one example of compacting the DCI that can be supported in NOMA transmissions in the present disclosure in order to reduce the signaling overhead of dynamic DCI. In one aspect, a group common PDCCH can be reused. As shown in <FIG>, the RMSI for a common resource allocation can be reused. The CRC for the group common PDCCH and/or RMSI for common resource allocation can be scrambled by NOMA group RNTI. In some aspects, a group common PDCCH can be used, so each UE in the cell can monitor the search space for the PDCCH. Additionally, in some aspects the payload size of the group common PDCCH can be limited, so the common or shared resources can be used in order to keep the payload size low. A multi-cast or broadcast signal may be used to carry the common resource allocation. Accordingly, some aspects can consider a group common PDCCH for the common resource allocation. In other aspects, the PDCCH and RMSI can be payload based, and the CRC for both the PDCCH and RMSI can be scrambled by the NOMA group RNTI.

In another aspect, a modified DCI format may be used for NOMA, in addition to a MCS table comprising NOMA specific transmission parameters. As shown in <FIG>, NOMA specific transmission parameters can be included with the MCS table entries. For instance, these NOMA specific transmission parameters can include any of a spreading factor, a seed of scrambling code, and layers for multi-branch transmission. Some entries of the new MCS table can be customized for NOMA specific transmission parameters. For example, the MCS table can include an entry for a spreading factor, a seed of scrambling code, or layers for multi-branch transmission.

In yet another aspect, a multi-stage DCI scrambled by a NOMA group RNTI may be used. In some aspects, the system bandwidth can be wide, so that the system bandwidth can accommodate both NOMA and OMA transmissions. A common subspace may be used to carry the NOMA specific group common PDCCH. The subspace can be monitored, whether using OMA or NOMA UEs. From power savings perspective, these types of transmissions can be used with NOMA UEs, as OMA UEs may not have a grant. Additionally, these transmissions can be performed in multiple steps. Further, this can enable power savings for OMA UEs, as once OMA UEs detect the first stage DCI, then the wireless system can stop the signal processing and save power. A NOMA UE that is able to decode the first stage of the DCI based on the NOMA group RNTI, will continue to receive and decode the additional stages of the multi-stage DCI.

In another aspect of the present disclosure, in order to reduce the payload size of a configured grant for the first transmissions and HARQ re-transmissions, a compressed form of a configured grant can be supported. In some aspects, configured grant or grant-free transmissions can be carried by RRC and choose the first transmission. As mentioned above, in NOMA transmissions, the first transmission and the retransmissions can be configured. Accordingly, the configured grant can cover the first transmission and any re-transmissions. The grant to the UE may reference a table of transport formats applicable to NOMA. For example, the UE may use a new lookup table to identify the transport format for the UE from the grant. A lookup table may be built between the first and re-transmission, e.g., in order to simplify the signaling. For example, if a pre-configuration includes a first transmission using a certain spreading factor and a re-transmission using a larger spreading factor, aspects presented herein can simplify this process through use of a lookup table. Further, some aspects can use a bit in the RRC payload to identify whether the transmissions are activated or deactivated.

In another aspect, a compressed form of configured grant can utilize an index or number the transport formats available to different NOMA schemes. For instance, the possible combinations for the first transmission and re-transmissions can be enumerated. For example, an MCS or NOMA specific transmission scheme can have a table to list the possible combinations. The grant to the UE may comprise and index, and the UE can use an index to identify the corresponding transport format. Additionally, a compressed form of configured grant can select one or a subset of transport formats, and transmit the index in the payload of RRC signaling. In some aspects, the index can be of the corresponding transport format. As such, in these aspects, the index can be transmitted, not the details the payload of RRC signaling. As the index may need to be transmitted to the UE in the grant, this is an efficient way to signal the information for the first and re-transmissions.

<FIG> is a diagram <NUM> illustrating transmissions between base station <NUM> and UE <NUM>. For instance, base station <NUM> can transmit <NUM> DCI or a semi-static uplink resource grant <NUM> to UE <NUM> allocated for NOMA communication. A payload of the DCI or the semi-static uplink resource grant can be scrambled with a NOMA group RNTI or comprise NOMA transmission parameters indicated by an extended MCS table. UE <NUM> can receive <NUM> the DCI or semi-static uplink resource grant from base station <NUM> allocated for NOMA communication.

The DCI can be received based on at least one of a group common control channel or RMSI for a common resource allocation. The DCI may also comprise a CRC that is scrambled by the NOMA group RNTI. Additionally, the DCI can comprise one or more NOMA transmission parameters indicated by the extended MCS table, as described in connection with the example in <FIG>. The one or more NOMA transmission parameters can comprise at least one of a spreading factor for a NOMA transmission, a seed of scrambling code for the NOMA transmission, and one or more layers for multiple branch transmission of the NOMA transmission, as mentioned above in connection with the example in <FIG>. The DCI can also comprise a multiple stage DCI scrambled by the NOMA group RNTI.

Base station <NUM> can also transmit <NUM> a compressed uplink resource grant by RRC signaling or a compact DCI by PDCCH <NUM>. In turn, UE <NUM> can receive <NUM> the compressed uplink resource grant by RRC signaling or compact DCI by PDCCH. The compressed uplink resource grant can be based on a table of NOMA transport formats. Also, the compressed uplink resource grant can indicate an index for a transport format from among multiple transport formats for the uplink NOMA communication. Further, the compressed uplink resource grant can comprise an index of at least one transport format that is received through RRC signaling.

UE <NUM> can also transmit <NUM> uplink NOMA communication <NUM> to the base station based on DCI or a semi-static uplink resource grant. Finally, base station <NUM> can receive <NUM> uplink NOMA communication from the UE based on the DCI or semi-static uplink resource grant.

At <NUM>, the UE can receive DCI or semi-static uplink resource grant from the base station allocated for NOMA communication. For example, reception component <NUM> of apparatus <NUM> may receive DCI or semi-static uplink resource grant from the base station allocated for NOMA communication. A payload of the DCI or the semi-static uplink resource grant can be scrambled with a NOMA group RNTI or comprise NOMA transmission parameters indicated by an extended MCS table, as described in connection with the example in <FIG>. The DCI can be received based on at least one of a group common control channel or RMSI for a common resource allocation. The DCI also comprise a CRC that is scrambled by the NOMA group RNTI. Further, the DCI can comprise one or more NOMA transmission parameters indicated by the extended MCS table. The one or more NOMA transmission parameters can comprise at least one of a spreading factor for a NOMA transmission, a seed of scrambling code for the NOMA transmission, and one or more layers for multiple branch transmission of the NOMA transmission, as mentioned above in connection with the example in <FIG>. The DCI can also comprise a multiple stage DCI scrambled by the NOMA group RNTI.

At <NUM>, the UE can receive the compressed uplink resource grant by RRC signaling or compact DCI by PDCCH. For example, reception component <NUM> of apparatus <NUM> may receive the compressed uplink resource grant by RRC signaling or compact DCI by PDCCH. The compressed uplink resource grant can be based on a table of NOMA transport formats. Also, the compressed uplink resource grant can indicate an index for a transport format from among multiple transport formats for the uplink NOMA communication. The compressed uplink resource grant can comprise an index of at least one transport format that is received through RRC signaling.

Finally, at <NUM>, the UE can transmit uplink NOMA communication to the base station based on DCI or a semi-static uplink resource grant. For example, transmission component <NUM> of apparatus <NUM> may transmit uplink NOMA communication to the base station based on DCI or a semi-static uplink resource grant.

<FIG> is a conceptual data flow diagram <NUM> illustrating the data flow between different means/components in an exemplary apparatus <NUM>. The apparatus may be a UE or a component of a UE. The apparatus can include a reception component <NUM> that is configured to receive DCI or semi-static uplink resource grant from a base station allocated for NOMA communication. NOMA compression component <NUM> can also be configured to receive compressed uplink resource grant by RRC signaling. NOMA compaction component <NUM> can be configured to receive compact DCI by PDCCH. The apparatus can also include a transmission component <NUM> that is configured to transmit uplink communication to base station <NUM>. The apparatus can also include a NOMA transmission component <NUM> that is configured to transmit uplink NOMA communication to base station based on DCI or semi-static uplink resource grant.

<FIG> is a diagram <NUM> illustrating an example of a hardware implementation for an apparatus <NUM>' employing a processing system <NUM>. The processing system <NUM> may be implemented with a bus architecture, represented generally by the bus <NUM>. The bus <NUM> may include any number of interconnecting buses and bridges depending on the specific application of the processing system <NUM> and the overall design constraints. The bus <NUM> links together various circuits including one or more processors and/or hardware components, represented by the processor <NUM>, the components <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and the computer-readable medium / memory <NUM>. The bus <NUM> may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, will not be described any further.

The processing system <NUM> may be coupled to a transceiver <NUM>. The transceiver <NUM> is coupled to one or more antennas <NUM>. The transceiver <NUM> provides a means for communicating with various other apparatus over a transmission medium. The transceiver <NUM> receives a signal from the one or more antennas <NUM>, extracts information from the received signal, and provides the extracted information to the processing system <NUM>, specifically the reception component <NUM>. In addition, the transceiver <NUM> receives information from the processing system <NUM>, specifically the transmission component <NUM>, and based on the received information, generates a signal to be applied to the one or more antennas <NUM>. The processing system <NUM> includes a processor <NUM> coupled to a computer-readable medium / memory <NUM>. The processor <NUM> is responsible for general processing, including the execution of software stored on the computer-readable medium / memory <NUM>. The software, when executed by the processor <NUM>, causes the processing system <NUM> to perform the various functions described supra for any particular apparatus. The computer-readable medium / memory <NUM> may also be used for storing data that is manipulated by the processor <NUM> when executing software. The processing system <NUM> further includes at least one of the components <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. The components may be software components running in the processor <NUM>, resident/stored in the computer readable medium / memory <NUM>, one or more hardware components coupled to the processor <NUM>, or some combination thereof. The processing system <NUM> may be a component of the UE <NUM> and may include the memory <NUM> and/or at least one of the TX processor <NUM>, the RX processor <NUM>, and the controller/processor <NUM>. Alternatively, the processing system <NUM> may comprise the entire UE, e.g., UE <NUM>.

In one configuration, the apparatus <NUM>/<NUM>' for wireless communication includes means for receiving DCI or a semi-static uplink resource grant from a base station allocated for NOMA communication with the base station. The DCI can be scrambled with a NOMA group RNTI or comprises NOMA transmission parameters indicated by an extended MCS table. The apparatus can also include means for receiving a compact DCI signaled by PDCCH or a compressed uplink resource grant signaled by a RRC. The apparatus can also include means for transmitting uplink NOMA communication to the base station based on the DCI or a semi-static uplink resource grant received from the base station.

At <NUM>, the base station can transmit DCI or semi-static uplink resource grant to the UE allocated for NOMA communication. For example, transmission component <NUM> of apparatus <NUM> may transmit DCI or semi-static uplink resource grant to the UE allocated for NOMA communication. A payload of the DCI or the semi-static uplink resource grant can be scrambled with a NOMA group RNTI or comprise NOMA transmission parameters indicated by an extended MCS table, as described in connection with the example in <FIG>. The DCI can be received based on at least one of a group common control channel or RMSI for a common resource allocation. The DCI also comprise a CRC that is scrambled by the NOMA group RNTI. Also, the DCI can comprise one or more NOMA transmission parameters indicated by the extended MCS table. The one or more NOMA transmission parameters can comprise at least one of a spreading factor for a NOMA transmission, a seed of scrambling code for the NOMA transmission, and one or more layers for multiple branch transmission of the NOMA transmission, as mentioned above in connection with the example in <FIG>. The DCI can also comprise a multiple stage DCI scrambled by the NOMA group RNTI.

At <NUM>, the base station can transmit the compressed uplink resource grant by RRC signaling or compact DCI by PDCCH. For example, transmission component <NUM> of apparatus <NUM> may transmit the compressed uplink resource grant by RRC signaling or compact DCI by PDCCH. The compressed uplink resource grant can be based on a table of NOMA transport formats. Further, the compressed uplink resource grant can indicate an index for a transport format from among multiple transport formats for the uplink NOMA communication. The compressed uplink resource grant can comprise an index of at least one transport format that is received through RRC signaling.

Finally, at <NUM>, the base station can receive uplink NOMA communication from the UE based on DCI or a semi-static uplink resource grant. For example, reception component <NUM> of apparatus <NUM> may receive uplink NOMA communication from the UE based on DCI or a semi-static uplink resource grant.

<FIG> is a conceptual data flow diagram <NUM> illustrating the data flow between different means/components in an exemplary apparatus <NUM>. The apparatus may be a base station or a component of a base station. The apparatus includes a transmission component <NUM> that is configured to transmit DCI or semi-static uplink resource grant to a UE allocated for NOMA communication. NOMA transmission component <NUM> can also be configured to transmit compressed uplink resource grant by RRC signaling or compact DCI by PDCCH. The apparatus can also include a reception component <NUM> that is configured to receive uplink communication from UE <NUM>. NOMA compaction component <NUM> can be configured to receive uplink NOMA communication from the UE based on DCI. NOMA compression component <NUM> can also be configured to receive uplink NOMA communication from the UE based on semi-static uplink resource grant.

The processing system <NUM> may be coupled to a transceiver <NUM>. The transceiver <NUM> is coupled to one or more antennas <NUM>. The transceiver <NUM> provides a means for communicating with various other apparatus over a transmission medium. The transceiver <NUM> receives a signal from the one or more antennas <NUM>, extracts information from the received signal, and provides the extracted information to the processing system <NUM>, specifically the reception component <NUM>. In addition, the transceiver <NUM> receives information from the processing system <NUM>, specifically the transmission component <NUM>, and based on the received information, generates a signal to be applied to the one or more antennas <NUM>. The processing system <NUM> includes a processor <NUM> coupled to a computer-readable medium / memory <NUM>. The processor <NUM> is responsible for general processing, including the execution of software stored on the computer-readable medium / memory <NUM>. The software, when executed by the processor <NUM>, causes the processing system <NUM> to perform the various functions described supra for any particular apparatus. The computer-readable medium / memory <NUM> may also be used for storing data that is manipulated by the processor <NUM> when executing software. The processing system <NUM> further includes at least one of the components <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. The components may be software components running in the processor <NUM>, resident/stored in the computer readable medium / memory <NUM>, one or more hardware components coupled to the processor <NUM>, or some combination thereof. The processing system <NUM> may be a component of the base station <NUM> and may include the memory <NUM> and/or at least one of the TX processor <NUM>, the RX processor <NUM>, and the controller/processor <NUM>. Alternatively, the processing system <NUM> may comprise the entire base station, e.g., base station <NUM>.

In one configuration, the apparatus <NUM>/<NUM>' for wireless communication includes means for transmitting DCI or a semi-static uplink resource grant to a UE allocated for NOMA communication with the UE. A payload of the DCI or the semi-static uplink resource grant can be scrambled with a NOMA group RNTI or comprises NOMA transmission parameters indicated by an extended MCS table. The apparatus can also include means for transmitting a compressed uplink resource grant by RRC signaling or a compact DCI by a PDCCH. The apparatus can also include means for receiving uplink NOMA communication from the UE.

Claim 1:
A method of wireless communication at a User Equipment, UE, comprising:
receiving (<NUM>, <NUM>), from a base station, an indication of resources in time and frequency allocated for Non-Orthogonal Multiple Access, NOMA, communication with the base station, wherein the indication of resources comprises a set of NOMA resource units, NA-RUs, wherein the set of NA-RUs are mapped to a time frequency resource grid with respect to a synchronization signal block, SSB, based on at least one of a center frequency of an NA-RU or a number of physical resource blocks, PRBs, within each NA-RU in the set of NA-RUs, wherein the indication of resources is based on a mapping of the set of NA-RUs to a time frequency resource grid and indexed in a sequential order; and
transmitting (<NUM>, <NUM>) uplink NOMA communication to the base station based on the indication of resources received from the base station.