WO2021259734A1 - Cooperative blind decoding for downlink control information (dci) - Google Patents

Abstract

Embodiments include methods for a first user equipment (UE) to receive downlink control information (DCI) from a network node serving a cell in a wireless network. Such methods include monitoring PDCCH transmissions by the network node for DCI intended for UEs within a PDCCH monitoring group (PMG) that includes the first UE and at least a second UE. Such methods also include, upon detecting a DCI intended for the second UE, forwarding one of the following to the second UE via sidelink (SL) communications: decoded content of the detected DCI, or an indication of the detected DCFs location in a PDCCH search space. Other embodiments include complementary methods for the second UE and the network node, as well as UEs and network nodes configured to perform such methods.

Description

COOPERATIVE BLIND DECODING FOR DOWNLINK CONTROL

INFORMATION (DCI)

TECHNICAL FIELD

The present invention generally relates to wireless communication networks, and particularly relates to techniques for reducing energy consumption of wireless devices in relation to decoding downlink control information (DCI) transmitted by a network node serving a cell.

BACKGROUND

Currently the fifth generation (“5G”) of cellular systems, also referred to as New Radio (NR), is being standardized within the Third-Generation Partnership Project (3GPP). NR is developed for maximum flexibility to support many different use cases. These include mobile broadband, machine type communication (MTC), ultra-low latency critical communications (URLCC), side-link device-to-device (D2D), and several other use cases. The present disclosure relates generally to NR, but the following description of previous-generation technology is provided for context since it shares many features with NR.

LTE is an umbrella term that refers to radio access technologies developed within the Third-Generation Partnership Project (3 GPP) and initially standardized in Release 8 (Rel-8) and Release 9 (Rel-9), also known as Evolved UTRAN (E-UTRAN) LTE is targeted at various licensed frequency bands and is accompanied by improvements to non-radio aspects commonly referred to as System Architecture Evolution (SAE), which includes Evolved Packet Core (EPC) network. LTE continues to evolve through subsequent releases.

An overall exemplary architecture of a network comprising LTE and SAE is shown in Figure 1. E-UTRAN 100 includes one or more evolved Node B’s (eNB), such as eNBs 105, 110, and 115, and one or more user equipment (UE), such as UE 120. As used within the 3GPP standards, “user equipment” or “UE” means any wireless communication device ( e.g ., smartphone or computing device) that is capable of communicating with 3GPP-standard-compliant network equipment, including E-UTRAN as well as UTRAN and/or GERAN, as the third-generation (“3G”) and second-generation (“2G”) 3GPP RANs are commonly known.

As specified by 3GPP, E-UTRAN 100 is responsible for all radio-related functions in the network, including radio bearer control, radio admission control, radio mobility control, scheduling, and dynamic allocation of resources to UEs in uplink and downlink, as well as security of the communications with the UE. These functions reside in the eNBs, such as eNBs 105, 110, and 115. Each of the eNBs can serve a geographic coverage area including one more cells, including cells 106, 111, and 115 served by eNBs 105, 110, and 115, respectively. The eNBs in the E-UTRAN communicate with each other via the X2 interface, as shown in Figure 1. The eNBs also are responsible for the E-UTRAN interface to the EPC 130, specifically the SI interface to the Mobility Management Entity (MME) and the Serving Gateway (SGW), shown collectively as MME/S-GWs 134 and 138 in Figure 1. In general, the MME/S- GW handles both the overall control of the UE and data flow between the UE and the rest of the EPC. More specifically, the MME processes the signaling ( e.g ., control plane) protocols between the UE and the EPC, which are known as the Non-Access Stratum (NAS) protocols. The S-GW handles all Internet Protocol (IP) data packets (e.g., data or user plane) between the UE and the EPC and serves as the local mobility anchor for the data bearers when the UE moves between eNBs, such as eNBs 105, 110, and 115.

EPC 130 can also include a Home Subscriber Server (HSS) 131, which manages user- and subscriber-related information. HSS 131 can also provide support functions in mobility management, call and session setup, user authentication and access authorization. The functions of HSS 131 can be related to the functions of legacy Home Location Register (HLR) and Authentication Centre (AuC) functions or operations. HSS 131 can also communicate with MMEs 134 and 138 via respective S6a interfaces.

In some embodiments, HSS 131 can communicate with a user data repository (UDR) - labelled EPC-UDR 135 in Figure 1 - via a Ud interface. EPC-UDR 135 can store user credentials after they have been encrypted by AuC algorithms. These algorithms are not standardized (i.e., vendor-specific), such that encrypted credentials stored in EPC-UDR 135 are inaccessible by any other vendor than the vendor of HSS 131.

Figure 2 illustrates a block diagram of an exemplary control plane (CP) protocol stack between a UE, an eNB, and an MME. The exemplary protocol stack includes Physical (PHY), Medium Access Control (MAC), Radio Link Control (RLC), Packet Data Convergence Protocol (PDCP), and Radio Resource Control (RRC) layers between the UE and eNB. The PHY layer is concerned with how and what characteristics are used to transfer data over transport channels on the LTE radio interface. The MAC layer provides data transfer services on logical channels, maps logical channels to PHY transport channels, and reallocates PHY resources to support these services. The RLC layer provides error detection and/or correction, concatenation, segmentation, and reassembly, reordering of data transferred to or from the upper layers. The PDCP layer provides ciphering/deciphering and integrity protection for both CP and user plane (UP), as well as other UP functions such as header compression. The exemplary protocol stack also includes non-access stratum (NAS) signaling between the UE and the MME.

The RRC layer controls communications between a UE and an eNB at the radio interface, as well as the mobility of a UE between cells in the E-UTRAN. After a UE is powered ON it will be in the RRC IDLE state until an RRC connection is established with the network, at which time the UE will transition to RRC CONNECTED state ( e.g ., where data transfer can occur). The UE returns to RRC IDLE after the connection with the network is released. In RRC_ IDLE state, the UE does not belong to any cell, no RRC context has been established for the UE (e.g., in E- UTRAN), and the UE is out of UL synchronization with the network. Even so, a UE in RRC IDLE state is known in the EPC and has an assigned IP address.

Furthermore, in RRC IDLE state, the UE’s radio is active on a discontinuous reception (DRX) schedule configured by upper layers. During DRX active periods (also referred to as “DRX On durations”), an RRC IDLE UE receives system information (SI) broadcast by a serving cell, performs measurements of neighbor cells to support cell reselection, and monitors a paging channel for pages from the EPC via an eNB serving the cell in which the UE is camping.

A UE must perform a random-access (RA) procedure to move from RRC IDLE to RRC CONNECTED state. In RRC CONNECTED state, the cell serving the UE is known and an RRC context is established for the UE in the serving eNB, such that the UE and eNB can communicate. For example, a Cell Radio Network Temporary Identifier (C-RNTI) - a UE identity used for signaling between UE and network - is configured for a UE in RRC CONNECTED state.

The multiple access scheme for the LTE PHY is based on Orthogonal Frequency Division Multiplexing (OFDM) with a cyclic prefix (CP) in the downlink, and on Single-Carrier Frequency Division Multiple Access (SC-FDMA) with a cyclic prefix in the uplink. To support transmission in paired and unpaired spectrum, the LTE PHY supports both Frequency Division Duplexing (FDD) (including both full- and half-duplex operation) and Time Division Duplexing (TDD). A combination of a particular subcarrier in a particular symbol is known as a resource element (RE). Each RE is used to transmit a particular number of bits, depending on the type of modulation and/or bit-mapping constellation used for that RE. The radio resources of the LTE PHY are also defined in terms of physical resource blocks (PRBs). Each PRB spans N^RB _SC sub-carriers over the duration of a slot (i.e., N^DL _symb or N^DL _symb symbols), where N^RB _SC is typically either 12 or 24.

In general, an LTE physical channel corresponds to a set of REs carrying information that originates from higher layers. Downlink (i.e., eNB to UE) physical channels include Physical Downlink Shared Channel (PDSCH), Physical Downlink Control Channel (PDCCH), Physical Broadcast Channel (PBCH), etc. PDSCH is the main physical channel used for unicast downlink data transmission, but also for transmission of RAR (random access response), certain SI blocks, and paging information. PBCH carries the basic system information, required by the UE to access the network. PDCCH is used for transmitting downlink control information (DCI) including scheduling information for DL transmissions on PDSCH, grants for UL transmission on PUSCH, and channel quality feedback (e.g, CSI) for the UL channel. Uplink (i.e., UE to eNB) physical channels include Physical Uplink Shared Channel (PUSCH), Physical Uplink Control Channel (PUCCH), and Physical Random -Access Channel (PRACH). PUSCH is the uplink counterpart to the PDSCH. PUCCH is used by UEs to transmit uplink control information (UCI) including HARQ feedback for eNB DL transmissions, channel quality feedback ( e.g ., CSI) for the DL channel, scheduling requests (SRs), etc. PRACH is used for random access preamble transmission.

In addition, the LTE PHY includes various DL and UL reference signals, synchronization signals, and discovery signals. For example, demodulation reference signals (DM-RS) are transmitted in the DL (UL) to aid the UE (eNB) in the reception of an associated PDCCH (PUCCH) or PDSCH (PUSCH). Channel state information reference signals (CSI-RS) are transmitted in the DL to enable channel quality feedback by a UE. Sounding reference signals (SRS) are transmitted by UEs and enable the eNB to determine UL channel quality.

UL and DL data transmissions (e.g., on PUSCH and PDSCH, respectively) can take place with or without an explicit grant or assignment of resources by the network (e.g, eNB). In general, UL transmissions are usually referred to as being “granted” by the network ( i.e ., “UL grant”), while DL transmissions are usually referred to as taking place on resources that are “assigned” by the network (i.e., “DL assignment”). For transmission based on an explicit grant/assignment, DCI informs the UE of radio resources to use for UL transmission/DL reception. In contrast, a transmission/reception without an explicit grant/assignment is typically configured to occur with a defined periodicity according to a predefined configuration. Such transmissions can be referred to as semi-persistent scheduling (SPS), configured grant (CG), or grant-free transmissions.

Fifth generation (5G) NR technology shares many similarities with fourth generation (4G) LTE. For example, NR uses CP-OFDM (Cyclic Prefix Orthogonal Frequency Division Multiplexing) in the DL and both CP-OFDM and DFT-spread OFDM (DFT-S-OFDM) in the UL. As another example, in the time domain, NR DL and UL physical resources are organized into equal-sized 1-ms subframes. A subframe is further divided into multiple slots of equal duration, with each slot including multiple OFDM-based symbols. As another example, NR RRC layer includes RRC IDLE and RRC CONNECTED states, but adds an additional state known as RRC INACTIVE that has some properties similar to a “suspended” condition for LTE.

In addition to providing coverage via cells, as in LTE, NR networks also provide coverage via “beams.” In general, a DL “beam” is a coverage area of a network-transmitted RS that may be measured or monitored by a UE. In NR, for example, such RS can include any of the following, alone or in combination: SS/PBCH block (SSB), CSI-RS, tertiary reference signals (or any other sync signal), positioning RS (PRS), DMRS, phase-tracking reference signals (PTRS), etc. In general, SSB is available to all UEs regardless of RRC state, while other RS (e.g, CSI-RS, DM- RS, PTRS) are associated with specific UEs that have a network connection, i.e., in RRC CONNECTED state.

DCI is also used in NR to schedule DL transmissions of data to specific UEs (e.g., on PDSCH) and UL transmissions of data by specific UEs (e.g., on PUSCH). In some cases, the UE may not know in advance the DCI size used by the network, such that the UE must monitor for DCIs of different sizes. Support for advanced services used in 5G and future generations (e.g., 6G) is expected to create a need for more DCI sizes than currently available in LTE and NR. This can create various problems, issues, and/or difficulties with respect to UE complexity and energy consumption.

SUMMARY

Embodiments of the present disclosure provide specific improvements to communication between user equipment (UE) and network nodes in a wireless network, such as by providing, enabling, and/or facilitating solutions to overcome exemplary problems summarized above and described in more detail below.

Embodiments include methods (e.g., procedures) for a first user equipment (UE) to receive downlink control information (DCI) from a network node serving a cell in a wireless network. These exemplary methods can include monitoring physical downlink control channel (PDCCH) transmissions by the network node for DCI intended for a plurality of UEs (within a PDCCH monitoring group, PMG) that includes the first UE and at least a second UE. In some embodiments, the first UE can be a higher-complexity UE and the second UE can be a lower- complexity UE. These exemplary methods can also include, upon detecting a DCI intended for the second UE, forwarding one of the following to the second UE via sidelink (SL) communications: decoded content of the DCI, or an indication of a location of the DCI in a PDCCH search space (SS).

In some embodiments, these exemplary methods can also include detecting the DCI intended for the second UE. This can be based on one of the following operations: descrambling a cyclic redundancy check (CRC) associated with the DCI based on a radio network temporary identifier (RNTI) associated with the second UE; or descrambling the CRC associated with the DCI based on a RNTI associated with the first UE, and detecting information associated with the second UE in the (content of the) DCI.

In some embodiments, the first UE and the second UE can be within a coverage area of a first downlink (DL) beam associated with the cell. In such embodiments, these exemplary methods can also include measuring radio quality of reference signals associated with a plurality of DL beams associated with the cell, including the first DL beam; and reporting measured radio quality for at least the first DL beam to the network node. In various embodiments, the radio quality can be measured according to one or more of the following metrics: reference signal received power (RSRP), reference signal received quality (RSRQ), signal -to-interference-plus- noise ratio (SINR), received signal strength (RSSI), channel occupancy, listen-before-talk (LBT) failures, and clear channel assessment (CCA) failures.

In some of these embodiments, these exemplary methods can also include selecting the first DL beam as a preferred beam based on one or more of the following criteria: measured radio quality above a predetermined threshold; maximum measured radio quality among the plurality of beams; and measured radio quality according to at least two different metrics.

In some embodiments, these exemplary methods can also include receiving, from the network node, a configuration of the PMG. The PMG configuration can include indication of respective portions of a PDCCH SS that are assigned to respective UEs in the PMG, and/or indication of a resource pool for SL communications among UEs in the PMG. For example, monitoring PDCCH transmissions can be performed by the first UE in the portion of the SS assigned to the first UE. In some of these embodiments, the respective portions of the PDCCH SS differ from each other in one or more of the following aspects: search regions (SRs) in time and frequency; DCI sizes; DCI types; RNTI types; and required number of blind decodings. In some of these embodiments, the SRs regions for the first UE and the second UE are non overlapping in time and frequency.

In some embodiments, the configuration can also include a value of an added delay between a received DCI and a signal or channel scheduled via the received DCI. The added delay can be related to the forwarding via SL communications.

In some embodiments, the configuration can also include identifiers of UEs assigned to the PMG. In other embodiments, these exemplary methods can also include determining identifiers for UEs assigned to the PMG and transmitting the determined identifiers to the UEs assigned to the PMG via SL communications.

In other embodiments, the configuration can also indicate that the PMG is associated with one or more of the following: the cell, a DL beam, a carrier frequency, and a bandwidth part (BWP). In such embodiments, these exemplary methods can also include receiving, from the network node, a first assignment of the first UE to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG; and determining a second assignment of the first UE to the PMG based on the first assignment and the configuration.

Other embodiments include methods ( e.g procedures) for a second UE to receive DCI from a network node serving a cell in a wireless network. These exemplary methods can include monitoring PDCCH transmissions by the network node for DCI intended for the second UE, which is part of a PDCCH monitoring group (PMG) that also includes at least the first UE. In some embodiments, the first UE can be a higher-complexity UE and the second UE can be a lower- complexity UE. These exemplary methods can also include receiving one of the following from the first UE via SL communications: decoded content of a DCI intended for the second UE that was detected by the first UE, or an indication of the detected DCFs location in a first portion of a PDCCH SS monitored by the first UE but not the second UE.

In some embodiments, the first UE and the second UE are within a coverage area of a first DL beam associated with the cell. In such embodiments, these exemplary methods can also include measuring radio quality of reference signals associated with a plurality of DL beams associated with the cell, including the first DL beam; reporting measured radio quality for at least the first DL beam to the network node. In various embodiments, the radio quality can be measured according to one or more of the following metrics: RSRP, RSRQ, SINR, RSSI, channel occupancy, LBT failures, and CCA failures.

In some embodiments, these exemplary methods can also include selecting the first DL beam as a preferred beam based on one or more of the following criteria: measured radio quality above a predetermined threshold; maximum measured radio quality among the plurality of beams; and measured radio quality according to at least two different metrics.

In some embodiments, these exemplary methods can also include receiving, from the network node, a configuration of the PMG. The PMG configuration can include indication of respective portions of a PDCCH SS that are assigned to respective UEs in the PMG, and/or indication of a resource pool for SL communications among UEs in the PMG. For example, monitoring PDCCH transmissions can be performed by the second UE in the portion of the SS assigned to the second UE.

In some embodiments, the respective portions of the PDCCH SS differ from each other in one or more of the following aspects: SRs in time and frequency; DCI sizes; DCI types; RNTI types; and required number of blind decodings. In some embodiments, the SRs for the first UE and the second UE are non-overlapping in time and frequency.

In some embodiments, the configuration can also include a value of an added delay between a received DCI and a signal or channel scheduled via the received DCI. The added delay can be related to SL communications received from the first UE.

In some embodiments, the configuration can also include identifiers of UEs assigned to the PMG. In other embodiments, these exemplary methods can also include receiving, from the first UE via SL communications, identifiers of UEs assigned to the PMG.

In other embodiments, the configuration can also indicate that the PMG is associated with one or more of the following: the cell, a DL beam, a carrier frequency, and a BWP. In such embodiments, these exemplary methods can also include receiving, from the network node, a first assignment of the second UE to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG; and determining a second assignment of the second UE to the PMG based on the first assignment and the configuration.

Other embodiments include methods ( e.g ., procedures) for transmitting DCI to a plurality of UEs operating in a cell of a wireless network, according to various exemplary embodiments of the present disclosure. These exemplary methods can be performed by a network node (e.g., base station, eNB, gNB, ng-eNB, etc., or component thereof) serving the cell in the wireless network (e.g, E-UTRAN, NG-RAN).

These exemplary methods can include transmitting a configuration for a PDCCH monitoring group (PMG) that includes at least a first UE and a second UE. These exemplary methods can also include transmitting DCI intended for the second UE in a first portion of a PDCCH SS monitored by the first UE but not the second UE, in accordance with the PMG configuration.

In some embodiments, transmitting the DCI intended for the second UE can include either of the following: scrambling a CRC associated with the DCI based on a RNTI associated with the second UE; or including information associated with the second UE (in the content) of the DCI and scrambling the CRC associated with the DCI based on a RNTI associated with the first UE.

In various embodiments, the configuration can include any of the information and/or have any of the characteristics summarized above in relation to UE embodiments. For example, in some embodiments, the configuration can indicate that the PMG is associated with one or more of the following: the cell, a DL beam, a carrier frequency, and a BWP. In such embodiments, these exemplary methods can also include transmitting, to the first and second UEs, respective assignments of the first and second UEs to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG.

In some embodiments, these exemplary methods can also include transmitting a plurality of DL beams associated with the cell, including a first DL beam; and receiving, from the first and second UEs, reports of measured radio quality for at least the first DL beam. In various embodiments, the radio quality can be measured according to one or more of the following metrics: RSRP, RSRQ, SINR, RSSI, channel occupancy, LBT failures, and CCA failures. In some of these embodiments, these exemplary methods can also include, based on the reports, determining that the first and second UEs are in a coverage area of the first DL beam and assigning the first and second UEs to the PMG based on this determination.

Other embodiments include UEs (e.g., first and second UEs) and network nodes configured to perform operations corresponding to any of the exemplary methods described herein. Other exemplary embodiments include non-transitory, computer-readable media storing program instructions that, when executed by processing circuitry, configure such UEs and network nodes to perform operations corresponding to any of the exemplary methods described herein.

These and other embodiments facilitate splitting a DCI search space such that a lower- complexity UE can be assigned only a small subset of the search space, resulting in a low DCI blind decoding complexity or load for the UE. At the same time, a higher-complexity UE (e.g., with larger battery and/or more processing capabilities) can be assigned to perform blind decoding on behalf of lower-complexity UE(s) in the same PDCCH monitoring group and to forward any decoded DCI(s) that is(are) intended for these lower-complexity UE(s). In this manner, complexity and energy consumption associated with DCI blind decoding is decreased for the lower-complexity UEs.

These and other objects, features, and advantages of embodiments of the present disclosure will become apparent upon reading the following Detailed Description in view of the Drawings briefly described below.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a high-level block diagram of an exemplary architecture of the Long-Term Evolution (LTE) Evolved UTRAN (E-UTRAN) and Evolved Packet Core (EPC) network, as standardized by 3 GPP.

Figure 2 illustrates a block diagram of an exemplary control plane (CP) protocol stack between a UE, an eNB, and an MME.

Figure 3 illustrates a high-level view of an exemplary 5G/NR network architecture.

Figure 4 shows an exemplary frequency-domain configuration for a 5G/NR UE.

Figure 5 shows an exemplary time-frequency resource grid for an NR (e.g., 5G) slot.

Figures 6A-6B show exemplary NR slot configurations.

Figure 7 shows an example of using radio network temporary identifiers (RNTIs) to distinguish between downlink control information (DCI) intended for different UEs in the same cell.

Figure 8 shows an example of cooperative PDCCH monitoring among UEs in a physical downlink control channel (PDCCH) monitoring group, according to various embodiments of the present disclosure.

Figure 9 shows an exemplary division of a DCI monitoring space into four SRs associated with respective UEs of a PMG, according to various embodiments of the present disclosure. Figures 10-11 show flow diagrams of exemplary methods for first and second UEs (e.g., wireless devices, IoT devices, etc.), respectively, according to various embodiments of the present disclosure.

Figure 12 shows a flow diagram of an exemplary method for a network node (e.g, base station, eNB, gNB, ng-eNB, etc.) in a wireless network, according to various embodiments of the present disclosure.

Figure 13 shows a block diagram of an exemplary wireless device or UE, according to various exemplary embodiments of the present disclosure.

Figure 14 shows a block diagram of an exemplary network node according to various exemplary embodiments of the present disclosure.

Figure 15 shows a block diagram of an exemplary network configured to provide over- the-top (OTT) data services between a host computer and a UE, according to various exemplary embodiments of the present disclosure.

DETAILED DESCRIPTION

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

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

Furthermore, the following terms are used throughout the description given below:

• Radio Node: As used herein, a “radio node” can be either a “radio access node” or a

“wireless device.” • Radio Access Node: As used herein, a “radio access node” (or equivalently “radio network node,” “radio access network node,” or “RAN node”) can be any node in a radio access network (RAN) of a cellular communications network that operates to wirelessly transmit and/or receive signals. Some examples of a radio access node include, but are not limited to, a base station ( e.g ., a New Radio (NR) base station (gNB) in a 3GPP Fifth Generation (5G) NR network or an enhanced or evolved Node B (eNB) in a 3GPP LTE network), base station distributed components (e.g., CU and DU), a high-power or macro base station, a low-power base station (e.g, micro, pico, femto, or home base station, or the like), an integrated access backhaul (LAB) node, a transmission point, a remote radio unit (RRU or RRH), and a relay node.

• Core Network Node: As used herein, a “core network node” is any type of node in a core network. Some examples of a core network node include, e.g, a Mobility Management Entity (MME), a serving gateway (SGW), a Packet Data Network Gateway (P-GW), an access and mobility management function (AMF), a session management function (AMF), a user plane function (UPF), a Service Capability Exposure Function (SCEF), or the like.

• Wireless Device: As used herein, a “wireless device” (or “WD” for short) is any type of device that has access to (i.e., is served by) a cellular communications network by communicate wirelessly with network nodes and/or other wireless devices. Communicating wirelessly can involve transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information through air. Some examples of a wireless device include, but are not limited to, smart phones, mobile phones, cell phones, voice over IP (VoIP) phones, wireless local loop phones, desktop computers, personal digital assistants (PDAs), wireless cameras, gaming consoles or devices, music storage devices, playback appliances, wearable devices, wireless endpoints, mobile stations, tablets, laptops, laptop- embedded equipment (LEE), laptop-mounted equipment (LME), smart devices, wireless customer-premise equipment (CPE), mobile-type communication (MTC) devices, Internet-of-Things (IoT) devices, vehicle-mounted wireless terminal devices, etc. Unless otherwise noted, the term “wireless device” is used interchangeably herein with the term “user equipment” (or “UE” for short).

• Network Node: As used herein, a “network node” is any node that is either part of the radio access network (e.g, a radio access node or equivalent name discussed above) or of the core network (e.g, a core network node discussed above) of a cellular communications network. Functionally, a network node is equipment capable, configured, arranged, and/or operable to communicate directly or indirectly with a wireless device and/or with other network nodes or equipment in the cellular communications network, to enable and/or provide wireless access to the wireless device, and/or to perform other functions ( e.g administration) in the cellular communications network.

Note that the description herein focuses on a 3 GPP cellular communications system and, as such, 3GPP terminology or terminology similar to 3GPP terminology is oftentimes used. However, the concepts disclosed herein are not limited to a 3GPP system. Furthermore, although the term “cell” is used herein, it should be understood that (particularly with respect to 5G NR) beams may be used instead of cells and, as such, concepts described herein apply equally to both cells and beams.

As briefly mentioned above, support for advanced services used in 5G and future generations (e.g., 6G) is expected to create a need for more sizes of downlink control information (DCI) used to schedule DL and UL data transmissions by UEs. This can create various problems, issues, and/or difficulties with respect to UE complexity and energy consumption. This is discussed in more detail below, after the following description of NR network architectures and radio interface.

Figure 3 illustrates a high-level view of the 5G network architecture, consisting of a Next Generation RAN (NG-RAN) 399 and a 5G Core (5GC) 398. NG-RAN 399 can include a set of gNodeB’s (gNBs) connected to the 5GC via one or more NG interfaces, such as gNBs 300, 350 connected via interfaces 302, 352, respectively. In addition, the gNBs can be connected to each other via one or more Xn interfaces, such as Xn interface 340 between gNBs 300 and 350. With respect the NR interface to UEs, each of the gNBs can support frequency division duplexing (FDD), time division duplexing (TDD), or a combination thereof.

NG-RAN 399 is layered into a Radio Network Layer (RNL) and a Transport Network Layer (TNL). The NG-RAN architecture, i.e., the NG-RAN logical nodes and interfaces between them, is defined as part of the RNL. For each NG-RAN interface (NG, Xn, FI) the related TNL protocol and the functionality are specified. The TNL provides services for user plane transport and signaling transport. In some exemplary configurations, each gNB is connected to all 5GC nodes within an “AMF Region,” which is defined in 3GPP TS 23.501. If security protection for CP and UP data on TNL of NG-RAN interfaces is supported, NDS/IP shall be applied.

The NG RAN logical nodes shown in Figure 3 (and described in 3GPP TS 38.301 and 3 GPP TR 38.801) include a central (or centralized) unit (CU or gNB-CU) and one or more distributed (or decentralized) units (DU or gNB-DU). For example, gNB 300 includes gNB-CU 310 and gNB-DUs 320 and 340. CUs (e.g., gNB-CU 310) are logical nodes that host higher-layer protocols and perform various gNB functions such controlling the operation of DUs. Each DU is a logical node that hosts lower-layer protocols and can include, depending on the functional split, various subsets of the gNB functions. As such, each of the CUs and DUs can include various circuitry needed to perform their respective functions, including processing circuitry, transceiver circuitry ( e.g ., for communication), and power supply circuitry. Moreover, the terms “central unit” and “centralized unit” are used interchangeably herein, as are the terms “distributed unit” and “decentralized unit.”

A gNB-CU connects to gNB-DUs over respective FI logical interfaces, such as interfaces 322 and 332 shown in Figure 3. The gNB-CU and connected gNB-DUs are only visible to other gNBs and the 5GC as a gNB. In other words, the FI interface is not visible beyond gNB-CU.

Figure 4 shows an exemplary frequency-domain configuration for an NR UE. In Rel-15 NR, a UE can be configured with up to four carrier bandwidth parts (BWPs) in the DL with a single DL BWP being active at a given time. A UE can be configured with up to four BWPs in the UL with a single UL BWP being active at a given time. If a UE is configured with a supplementary UL, the UE can be configured with up to four additional BWPs in the supplementary UL, with a single supplementary UL BWP being active at a given time. In the exemplary arrangement of Figure 4, the UE is configured with three DL (or UL) BWPs, labelled BWP 0-2, respectively.

Common RBs (CRBs) are numbered from 0 to the end of the carrier bandwidth. Each BWP configured for a UE has a common reference of CRBO (as shown in Figure 4), such that a configured BWP may start at a CRB greater than zero. CRBO can be identified by one of the following parameters provided by the network, as further defined in 3GPP TS 38.211 section 4.4:

• PRB-index-DL-common for DL in a primary cell (PCell, e.g., PCell or PSCell);

• PRB-index-UL-common for UL in a PCell;

• PRB-index-DL-Dedicated for DL in a secondary cell (SCell);

• PRB-index-UL-Dedicated for UL in an SCell; and

• PRB-index-SUL-common for a supplementary UL.

In this manner, a UE can be configured with a narrow BWP (e.g., 10 MHz) and a wide BWP (e.g, 100 MHz), each starting at a particular CRB, but only one BWP can be active for the UE at a given point in time. In the arrangement shown in Figure 5, BWPs 0-2 start at CRBs N°_BW_P, N^W_P, and N² _BW_P, respectively. Within a BWP, PRBs are defined and numbered in the frequency domain from 0 to ^BWP; ^_1 , where i is the index of the particular BWP for the carrier. In the arrangement shown in Figure 4, BWPs 0-2 include PRBs 0 to Nl, N2, and N3, respectively.

Similar to LTE, each NR resource element (RE) corresponds to one OFDM subcarrier during one OFDM symbol interval. NR supports various SCS values D/ = (15 X 2^m) kHz, where m e (0,1, 2, 3, 4) are referred to as “numerologies.” Numerology m = 0 (/. ., D/ = 15 kHz) provides the basic (or reference) SCS that is also used in LTE. The symbol duration, cyclic prefix (CP) duration, and slot duration are inversely related to SCS or numerology. For example, there is one (1-ms) slot per subframe for D/ = 15 kHz, two 0.5-ms slots per subframe for D/ = 30 kHz, etc. In addition, the maximum carrier bandwidth is directly related to numerology according to 2^m * 50 MHz. Table 1 below summarizes the supported NR numerologies and associated parameters. Different DL and UL numerologies can be configured by the network.

Table 1.

Figure 5 shows an exemplary time-frequency resource grid for an NR slot. As illustrated in Figure 5, a resource block (RB) consists of a group of 12 contiguous OFDM subcarriers for a duration of a 14-symbol slot. Like in LTE, a resource element (RE) consists of one subcarrier in one slot. An NR slot can include 14 OFDM symbols for normal cyclic prefix (e.g., as shown in Figure 5) and 12 symbols for extended cyclic prefix. Figure 6A shows an exemplary NR slot configuration comprising 14 symbols, where the slot and symbols durations are denoted T_s and T_symb , respectively. In addition, NR includes a Type-B scheduling, also known as “mini-slots.” These are shorter than slots, typically ranging from one symbol up to one less than the number of symbols in a slot (e.g., 13 or 11), and can start at any symbol of a slot. Figure 6B shows another exemplary NR slot structure comprising 14 symbols. In this arrangement, PDCCH is confined to a region containing a particular number of symbols and a particular number of subcarriers, referred to as the control resource set (CORESET). In the exemplary structure shown in Figure 6B, the first two symbols contain PDCCH and each of the remaining 12 symbols contains physical data channels (PDCH), i.e., either PDSCH or PUSCH. Depending on the specific CORESET configuration, however, the first two slots can also carry PDSCH or other information, as required. Nevertheless, a CORESET merely indicates where a device may receive (or monitor for) PDCCH transmissions and does not require a gNB to transmit PDCCH when there is no information to provide the UE. A CORESET includes multiple RBs (i.e., multiples of 12 REs) in the frequency domain and 1-3 OFDM symbols in the time domain, as further defined in 3GPP TS 38.211 § 7.3.2.2. CORESET resources can start at any symbol of a slot, with the arrangement shown in Figure 6B being exemplary. The smallest unit used for defining CORESET is resource element group (REG), which spans one PRB in frequency and one OFDM symbol in time. A CORESET is functionally similar to the control region in LTE subframe. In NR, however, each REG consists of all 12 REs of one OFDM symbol in an RB, whereas an LTE REG includes only four REs. Like in LTE, the CORESET time domain size can be indicated by PCFICH. In LTE, the frequency bandwidth of the control region is fixed (i.e., to the total system bandwidth), whereas in NR, the frequency bandwidth of the CORESET is variable (e.g., within a specific region of the total system bandwidth). Even so, a UE is not expected to monitor CORESET resources outside of its active BWP. CORESET resources can be indicated to a UE by RRC signaling.

In addition to PDCCH, each REG in a CORESET contains demodulation reference signals (DMRS) to aid in the estimation of the radio channel over which that REG was transmitted. When transmitting the PDCCH, a precoder can be used to apply weights at the transmit antennas based on some knowledge of the radio channel prior to transmission. It is possible to improve channel estimation performance at the UE by estimating the channel over multiple REGs that are proximate in time and frequency, if the precoder used at the transmitter for the REGs is not different. To assist the UE with channel estimation, multiple REGs can be grouped together to form a REG bundle, and the REG bundle size for a CORESET (i.e., 2, 3, or 5 REGs) can be indicated to the UE. The UE can assume that any precoder used for the transmission of the PDCCH is the same for all the REGs in a REG bundle.

An NR control channel element (CCE) consists of six REGs. These REGs may either be contiguous or distributed in frequency. When the REGs are distributed in frequency, the CORESET is said to use interleaved mapping of REGs to a CCE, while if the REGs are contiguous in frequency, a non-interleaved mapping is said to be used. Interleaving can provide frequency diversity. Not using interleaving is beneficial for cases where knowledge of the channel allows the use of a precoder in a particular part of the spectrum improve the SINR at the receiver.

Similar to LTE, NR data scheduling can be performed dynamically, e.g., on a per-slot basis. In each slot, the base station (e.g, gNB) transmits downlink control information (DCI) over PDCCH that indicates which UE is scheduled to receive data in that slot, as well as which RBs will carry that data. A UE first detects and decodes DCI and, if the DCI includes DL scheduling information for the UE, receives the corresponding PDSCH based on the DL scheduling information. DCI formats 1 0 and 1 1 are used to convey PDSCH scheduling. Likewise, DCI on PDCCH can include UL grants that indicate which UE is scheduled to transmit data on PUCCH in that slot, as well as which RBs will carry that data. A UE first detects and decodes DCI and, if the DCI includes an uplink grant for the UE, transmits the corresponding PUSCH on the resources indicated by the UL grant. DCI formats 0 0 and 0 1 are used to convey UL grants for PUSCH, while other DCI formats (2 0, 2 1, 2 2 and 2 3) are used for other purposes including transmission of slot format information, reserved resource, transmit power control information, etc.

In NR Rel-15, the DCI formats 0 0/1 0 are referred to as “fallback DCI formats,” while the DCI formats 0 1/1 1 are referred to as “non-fallback DCI formats.” The fallback DCI formats support resource allocation type 1 in which DCI size depends on the size of active BWP. As such, DCI formats 0 1/1 1 are intended for scheduling a single transport block (TB) transmission with limited flexibility. On the other hand, the non-fallback DCI formats can provide flexible TB scheduling with multi-layer transmission. As such, an NR UE needs to monitor for up to four different DCI sizes: one for fallback DCI formats, one non-fallback for DL scheduling assignments, one non-fallback for UL grants (unless size-aligned with DL), and one for a slot-format indication and/or a preemption indication.

A DCI includes a payload complemented with a Cyclic Redundancy Check (CRC) of the payload data. Since DCI is sent on PDCCH that is received by multiple UEs, an identifier of the targeted UE needs to be included. In NR, this is done by scrambling the CRC with a Radio Network Temporary Identifier (RNTI) assigned to the UE. Most commonly, the cell RNTI (C- RNTI) assigned to the targeted UE by the serving cell is used for this purpose. However, other identifiers (e.g., for paging, random access, etc.) can also be used for this purpose. DCI payload together with an identifier-scrambled CRC is encoded and transmitted on the PDCCH.

Figure 7 shows an example of using RNTIs to distinguish between DCIs intended for different UEs in the same cell. In the arrangement shown in Figure 7, a gNB serving UE1 and UE2 in a cell has assigned RNTI to LEI and RNTI2 to UE2. Subsequently, the gNB transmits a PDCCH that includes DCI1 intended for LEI and DCI2 intended for UE2. DCIl’s CRC is scrambled by RNTI1 and DCI2’s CRC is scrambled by RNTI2. Accordingly, LEI can decode DCI1 but not DCI2, while UE2 can decode DCI2 but not DCI1. From a UE point of view, however, there is no difference between a corrupt DCI (e.g., non-checking CRC) intended for the UE and a DCI intended for another UE (e.g., CRC scrambled by another RNTI).

Given previously configured search spaces, each UE tries to detect a PDCCH addressed to it according to multiple hypotheses (also referred to as “candidates”) in a process known as “blind decoding.” PDCCH candidates span 1, 2, 4, 8, or 16 CCEs, with the number of CCEs referred to as the aggregation level (AL) of the PDCCH candidate. If more than one CCE is used, the information in the first CCE is repeated in the other CCEs. By varying AL, PDCCH can be made more or less robust for a certain payload size. In other words, PDCCH link adaptation can be performed by adjusting AL. Depending on AL, PDCCH candidates can be located at various time-frequency locations in the CORESET.

A hashing function can be used to determine the CCEs corresponding to PDCCH candidates that a UE must monitor within a search space set. The hashing is done differently for different UEs. In this manner, CCEs used by the UEs are randomized and the probability of collisions between multiple UEs having messages included in a CORESET is reduced. Once a UE decodes a DCI, it de-scrambles the CRC with RNTI(s) that is(are) assigned to it and/or associated with the particular PDCCH search space. In case of a match, the UE considers the detected DCI as being addressed to it, and follows the instructions ( e.g scheduling information) in the DCI.

For example, to determine the modulation order, target code rate, and TB size(s) for a scheduled PDSCH transmission, the UE first reads the 5-bit modulation and coding scheme field (I_MCS) in the DCI (e.g., formats 1 0 or 1 1) to determine the modulation order (Q_m) and target code rate ( R ) based on the procedure defined in 3GPP TS 38.214 V15.0.0 clause 5.1.3.1. Subsequently, the UE reads the redundancy version field (rv) in the DCI to determine the redundancy version. Based on this information together with the number of layers (u) and the total number of allocated PRBs before rate matching ( npw ), the UE determines the Transport Block Size (TBS) for the PDSCH according to the procedure defined in 3GPP TS 38.214 V15.0.0 clause 5.1.3.2.

DCIs can also include information about various timing offsets (e.g., in slots or subframes) between PDCCH and PDSCH, PUSCH, HARQ, and/or CSI-RS. For example, offset K0 represents the number of slots between the UE’s PDCCH reception of a PDSCH scheduling DCI (e.g., formats 1 0 or 1 1) and the subsequent PDSCH transmission. Likewise, offset K1 represents the number of slots between this PDSCH transmission and the UE’s responsive HARQ ACK/NACK transmission on the PUSCH. Similarly, offset K3 represents the number of slots between this responsive ACK/NACK and the corresponding retransmission of data on PDSCH. In addition, offset K2 represents the number of slots between the UE’s PDCCH reception of a PUSCH grant DCI (e.g., formats 0 0 or 0 1) and the subsequent PUSCH transmission. Each of these offsets can take on values of zero and positive integers.

Offset K0 is part of a UE’s PDSCH time-domain resource allocation (TDRA) provided by the network node. Also included in the PDSCH TDRA is a slot length indicator values (SLIV), which identifies a particular combination of starting symbol (S) and length (L) of the time-domain allocation for PDSCH. In general, S can be any symbol 0-13 and L can be any number of symbols beginning with S until the end of the slot (i.e., symbol 13). The SLIV can be used as a look-up table index to find the associated (S, L) combination. Similarly, offset K2 is part of a UE’s PUSCH TDRA provided by the network node, which also includes a corresponding SLIV.

As mentioned above, the UE may not know in advance the DCI size used by the network, such that the UE must monitor for DCIs of different sizes. For example, in some scenarios, the UE must monitor for at least four different DCI sizes corresponding to different DCI formats. For each of the monitored sizes, the UE must perform blind decoding according to multiple hypotheses. This process is relatively complex and can consume a significant portion of a UE’s available energy supply (e.g., in a battery). Moreover, support for advanced services used in 5G and future generations (e.g., 6G) is expected to create a need for even more DCI sizes than currently available and/or used in LTE and NR. Using conventional blind decoding techniques for this expected greater number of DCI sizes will further increase UE complexity and energy consumption. These effects are undesirable, particularly for UEs (e.g., IoT devices) that are subject to strict complexity and/or energy consumption requirements.

Accordingly, embodiments of the present disclosure provide flexible and efficient techniques that facilitate splitting a DCI search space such that a lower-complexity UE can be assigned only a small subset of the search space that results in a low DCI blind decoding complexity or load. At the same time, a higher-complexity UE (e.g., with larger battery and/or more processing capabilities) can be assigned to perform blind decoding on behalf of lower- complexity UE(s) and can forward any decoded DCI(s) that is(are) intended for the lower- complexity UE(s). In this manner, the complexity and energy consumption associated with DCI blind decoding is decreased for the lower-complexity UEs.

At a high level, various embodiments are based on a “PDCCH monitoring group” (or PMG) that includes multiple UEs in the same beam coverage area. Put another way, the UEs in the PDCCH monitoring group can be located in the same cell and be associated with the same transmission configuration indicator (TCI) state configured by the network (e.g., gNB) within that cell. Even so, the term “PDCCH monitoring group” is merely exemplary and other terms and/or expressions can be used to refer to the same concept. Furthermore, various embodiments described herein are applicable to networks operating in licensed and/or unlicensed bands.

In various embodiments, the various UEs within a PDCCH monitoring group may have different capabilities in terms of DCI blind decoding complexity. For purposes of illustration, these will be referred to as “lower-complexity UEs” and “higher-complexity UEs.” Even so, there may be more than two levels of capability and/or complexity.

In some embodiments, a CORESET search space (SS) can be divided between UEs in a PDCCH monitoring group, such that each UE searches in a subset of the SS. Since the SS is divided into subsets, a lower-complexity UE can be assigned a small subset of the SS with reduced DCI load as compared to the total SS. In that subset, if that UE decodes a DCI intended for another UE, then the UE transmits that DCI to the other UE by device-to-device (D2D) communication.

In some embodiments, each UE in a cell can report its DCI blind decoding capability to a network node (e.g., gNB) serving the cell. The network node can then schedule the respective UEs using DCI sizes corresponding to the reported UE capabilities.

In some embodiments, the set of DCI sizes can be configured for each UE by the network, e.g., by RRC signaling. Once configured, a UE performs blind decoding based on the configured set of DCI sizes. As such, a UE may be configured to receive only a subset of the possible DCIs intended for it, with other intended DCIs being received and forwarded by other (higher complexity) UEs in the same PDCCH monitoring group.

In some embodiments, a RNTI used for receiving DCIs can be shared among UEs in a PDCCH monitoring group. The sharing may be indicated by RRC signaling from the network to the UEs in the group, and/or by signaling among the UEs via D2D communications (also referred to as sidelink, SL).

Figure 8 shows an example of cooperative PDCCH monitoring among UEs in a PDCCH monitoring group (PMG), according to various embodiments of the present disclosure. In the arrangement shown in Figure 8, UEl and UE2 are located in the same beam coverage are of a cell served by the gNB. The beam coverage area may be associated with an SSB or CSI-RS resource. Each UE in the group may be assigned with a unique ID. For example, the gNB has assigned RNTI to UEl and RNTI2 to UE2. In addition, the gNB has provided UEl with RNTI2 and UE2 with RNTI1, indicating that UEl and UE2 are in a PDCCH monitoring group. As such, UEl and UE2 are configured to monitor for both RNTI and RNTI2. In this manner, when UEl detects DCI2 scrambled with RNTI2, it then forwards DCI2 to UE2 via SL. Likewise, when UE2 detects DCI1 scrambled with RNTIl, it then forwards DCI1 to UEl via SL. In other arrangements, only one of UEl and UE2 can be configured to monitor for and forwarded detected DCIs addressed to the other UE in the PDCCH monitoring group.

In some embodiments, a DCI monitoring space (e.g., in CORESET time-frequency space) can be broken into multiple search regions (SRs), each associated with a different UE in a PDCCH monitoring group. The sizes and/or configurations of the respective SRs can be based on the capabilities of the respective UEs. Figure 9 shows an exemplary division of a DCI monitoring space into four SRs associated with respective UEs 1-4 of a PDCCH monitoring group. The exemplary division shown in Figure 9 is exclusive, such that there is no overlap between adjacent search regions for different UEs. In other embodiments, the SRs for different UEs may be non- exclusive such that multiple UEs may be assigned fully or partially overlapping SRs.

In some embodiments, each UE can use its assigned RNTI to receive DCIs intended for other UEs. This capability and/or requirement may be indicated in the DCI itself, e.g., by one or more bits. As such, the UE does not know that the DCI is intended for another UE until reading the DCI, e.g., after correct CRC descrambling and checking based on its own RNTI. In these embodiments, the number of extra bits needed in DCIs will vary based on the number of other UEs for which the DCI can be intended.

In some embodiments, different DCI sizes and/or PDCCH monitoring occasions (MOs) can be associated with different configured BWPs. As such, a UE can determine DCI blind decoding requirements based on which of the configured BWPs is the UE’s current active BWP.

Carrier aggregation (CA) was introduced in LTE Rel-10 to facilitate support for bandwidths larger than 20 MHz while remaining backward compatible with LTE Rel-8. In CA, a wideband LTE carrier (e.g., wider than 20 MHz) appears as multiple carriers (also referred to as “component carriers” or “CCs”) to a UE. Each CC can also be referred to as a “cell”, and the UE’s full set of CCs can be considered a “cell group”. In CA operation a UE is always assigned a primary cell (PCell, as a main serving cell) and may optionally be assigned one or more secondary cells (SCells). CA is also used in 5G/NR.

In some embodiments, different DCI sizes and/or PDCCH MOs can be associated with different configured cells and/or carriers (e.g., PCell, SCells, etc. used in CA). As such, a UE can determine DCI blind decoding requirements based on which of the configured cells and/or carriers are currently activated.

In some embodiments, a UE can continuously measure radio quality of the reference SSBs or CSI-RSs (e.g., of the corresponding beams) in the cell in which it is located. Such measurements can be based on reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference-plus-noise radio (SINR), received signal strength (RSSI), channel occupancy, listen-before-talk (LBT) and/or clear channel assessment (CCA) failures (e.g., count, ratio, etc.), or other suitable quantities. The UE provides CSI reports or handover (HO) measurement reports to the gNB indicating, e.g., the strongest beam(s). Based on the received measurement results, the gNB sends signaling to establish a PDCCH monitoring group among UEs in the coverage area of a particular beam. The signaling may be carried in broadcast system information, dedicated RRC signaling, MAC control element (CE), and/or DCI. The signaling carries configurations for the PDCCH monitoring group, which includes one or more of the following:

• UEs assigned to the PDCCH monitoring group and their associated UE IDs in the group. • Division of CORESET/PDCCH SS among UEs in the group (e.g., assignment of SRs in frequency and time domain, DCI sizes, number of blind decoding, etc.).

• Resource pool for D2D/SL communications among UEs in the group.

As an alternative, the UE IDs within a PDCCH monitoring group may be assigned by a group coordinator UE via SL communications among group members. The group coordinator UE may need to signal the UE ID assignments to the serving gNB for the group.

In some embodiments, the network can signal to UEs a list (e.g., a plurality) of PDCCH monitoring group configurations associated with a cell, a carrier, a BWP, a BWP segment, etc. The signaling may be carried in broadcast system information, dedicated RRC signaling, MAC CE, and/or DCI. Each PDCCH monitoring group configuration includes at least one of the below information or content:

• Division of CORESET/PDCCH SS among UEs in the group (e.g., SRs in frequency and time domain, DCI sizes, number of blind decoding, etc.).

• Resource pool for D2D/SL communications among UEs in the group, e.g., PSCCH or PDCCH resource for forwarding DCI over SL.

• Mapping or association of the configuration with at least one beam, e.g., an SSB or CSI- RS resource.

The UE can measure radio quality of the reference SSBs or CSI-RSs (e.g., of the corresponding beams) in the cell in which it is located. Such measurements can be based on RSRP, RSRQ, SINR, RSSI, channel occupancy, LBT/CCA failure statistics, etc. Based on the measurements, the UE may choose one or multiple preferred SSBs or CSI-RSs and select a PDCCH monitoring group configuration associated with the preferred SSB(s) or CSI-RS(s).

In some embodiments, a UE can select preferred SSBs or CSI-RSs based on one or more of the following criteria:

• Measured radio quality relative to one or more predetermined thresholds. For example, the UE can select the SSBs or CSI-RSs with measured quality (e.g., RSRP) above a first threshold, and then select any of these as the preferred SSB or CSI-RS. Alternately, the UE can select the one with the highest measured quality or select one of these based on another measurement (e.g., highest RSRQ or SINR).

• Only the SSB or CSI-RS with the strongest radio quality (e.g., RSRP). If there is no SSB or CSI-RS with the measured quality above a threshold, the UE can select any of these as the preferred SSB or CSI-RS. Alternatively, the UE can select the one with the highest measured quality or select one of these based on another measurement (e.g., highest RSRQ or SINR). • If all measured SSB or CSI-RS have quality above a threshold, the UE can select any of these as the preferred SSB or CSI-RS. Alternatively, the UE can select the one with the highest measured quality or select one of these based on another measurement (e.g., highest RSRQ or SINR).

In some embodiments, an additional delay value can be added to scheduling offsets K0, Kl, and/or K2. The additional delay value reflects the possible timing range for a SL transmission in case a DCI needs to be forwarded from a monitoring UE to another UE for which the DCI is intended. At least one of the following options may be employed:

• a fixed delay value is added to the K0, Kl, and/or K2 tables configured by RRC.

• the tables configured by RRC are not updated, but an additional delay value is added to the K0, Kl, and/or K2 values determined from parameters signaled in the DCI. The additional delay value for a group can be configured by the gNB and signaled to the UEs in the group.

As mentioned above, a higher-complexity UE can perform DCI monitoring on behalf of one or more lower-complexity UEs. In some embodiments, if the higher-complexity UE detects the DCI, it notifies a lower-complexity UE via SL about the DCFs location in the PDCCH resource grid without decoding the DCI (i.e. without determining the DCI content). Subsequently, the lower-complexity UE decodes the DCI from the indicated location rather than receiving it from the higher-complexity UE via SL, as in other embodiments.

In some embodiments, a parameter in a DCI transmission on PDCCH can indicate a DCI type and/or size to be used in a future DCI (i.e., the next one). This could be indicated by a header and/or a length field.

In some embodiments, each DCI can include or be associated with one of a plurality of mutually exclusive sequences of values, with each sequence corresponding to a type of service and/or size associated with a DCI. Example sequences include DMRS sequences, extended or modified DMRS sequences (e.g., that additionally represent UE ID and channel estimation information), or other sequences that are not jointly encoded in the DCI. As another example, the type of service can be indirectly mapped to the length, size, or type of DCI.

The embodiments described above are further illustrated by Figures 10-12, which depict exemplary methods performed by a first UE, a second UE, and a network node, respectively. In other words, various features of the operations described below, with reference to Figures 10-12, correspond to various embodiments described above. The exemplary methods illustrated by Figures 10-12 can be used cooperatively to provide various benefits, advantages, and/or solutions described herein. Although Figures 10-12 show specific blocks in particular orders, the operations of the exemplary methods can be performed in different orders than shown and can be combined and/or divided into blocks having different functionality than shown. Optional operations are indicated by dashed lines.

More specifically, Figure 10 is a flow diagram illustrating an exemplary method (e.g., procedure) for a first UE to receive DCI from a network node serving a cell in a wireless network, according to various embodiments of the present disclosure. The exemplary method shown in Figure 10 can be implemented, for example, by a UE (e.g., wireless device, IoT device, etc.) described elsewhere herein.

The exemplary method can include the operations of block 1050, where the first UE can monitor physical downlink control channel (PDCCH) transmissions by the network node for DCI intended for UEs within a PDCCH monitoring group (PMG) that includes the first UE and at least a second UE. In some embodiments, the first UE can be a higher-complexity UE and the second UE can be a lower-complexity UE. The exemplary method can also include the operations of block 1070, where the first UE can, upon detecting a DCI intended for the second UE, forward one of the following to the second UE via sidelink (SL) communications: decoded content of the detected DCI, or an indication of the detected DCFs location in a PDCCH search space (SS).

In some embodiments, the exemplary method can also include the operations of block 1060, where the first UE can detect the DCI intended for the second UE. This can be based on one of the following operations: descrambling a cyclic redundancy check (CRC) associated with the DCI based on a radio network temporary identifier (RNTI) associated with the second UE (sub-block 1061); or descrambling the CRC associated with the DCI based on a RNTI associated with the first UE, and detecting information associated with the second UE in the content of the DCI (sub-block 1062).

In some embodiments, the first UE and the second UE can be within a coverage area of a first downlink (DL) beam associated with the cell. In such embodiments, the exemplary method can also include the operations of blocks 1010-1020. In block 1010, the first UE can measure radio quality of reference signals associated with a plurality of DL beams associated with the cell, including the first DL beam. In block 1020, the first UE can report measured radio quality for at least the first DL beam to the network node. In various embodiments, the radio quality can be measured according to one or more of the following metrics: reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference-plus-noise ratio (SINR), received signal strength (RSSI), channel occupancy, listen-before-talk (LBT) failures, and clear channel assessment (CCA) failures.

In some of these embodiments, the exemplary method can also include the operations of block 1015, where the first UE can select the first DL beam as a preferred beam based on one or more of the following criteria: measured radio quality above a predetermined threshold; maximum measured radio quality among the plurality of beams; and measured radio quality according to at least two different metrics. The report of the measured radio quality for the first DL beam (e.g., in block 1020) can be based on the selection of the first DL beam as a preferred beam (e.g., in block 1015).

In some embodiments, the exemplary method can also include the operations of block 1025, where the first UE can receive, from the network node, a configuration of the PMG. The PMG configuration can include indication of respective portions of a PDCCH search space (SS) that are assigned to respective UEs in the PMG, and/or indication of a resource pool for SL communications among UEs in the PMG. For example, monitoring PDCCH transmissions can be performed by the first UE (e.g., in block 1050) in the portion of the SS assigned to the first UE.

In some of these embodiments, the respective portions of the PDCCH SS differ from each other in one or more of the following aspects: search regions (SRs) in time and frequency; DCI sizes; DCI types; radio network temporary identifier (RNTI) types; and required number of blind decodings. In some of these embodiments, the SRs regions for the first UE and the second UE are non-overlapping in time and frequency. An example is shown in Figure 9.

In some embodiments, the configuration (e.g., received in block 1025) can also include a value of an added delay between a received DCI and a signal or channel scheduled via the received DCI. The added delay can be related to the forwarding via SL communications (e.g., as performed in block 1070). For example, the added delay can be a value that is added to one or more of K0, Kl, and K2 values determined from parameters included in various DCI.

In some embodiments, the configuration (e.g., received in block 1025) can also include identifiers of UEs assigned to the PMG, e.g., by the network node. In other embodiments, the exemplary method can also include the operations of blocks 1030-1035, where the first UE can determine identifiers for UEs assigned to the PMG and transmit the determined identifiers to the UEs assigned to the PMG via SL communications.

In other embodiments, the configuration for the PMG (e.g., received in block 1025) can also indicate that the PMG is associated with one or more of the following: the cell, a downlink (DL) beam, a carrier frequency, and a bandwidth part (BWP). In such embodiments, the exemplary method can also include the operations of blocks 1040-1045. In block 1040, the first UE can receive, from the network node, a first assignment of the first UE to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG. In block 1045, the first UE can determine a second assignment of the first UE to the PMG based on the first assignment (e.g., received in block 1040) and the configuration (e.g., received in block 1025).

In addition, Figure 11 is a flow diagram illustrating an exemplary method (e.g., procedure) for a second UE to receive DCI from a network node serving a cell in a wireless network, according to various embodiments of the present disclosure. The exemplary method shown in Figure 11 can be implemented, for example, by a UE (e.g., wireless device, IoT device, etc.) described elsewhere herein.

The exemplary method can include the operations of block 1150, where the second UE can monitor PDCCH transmissions by the network node for DCI intended for the second UE, which is part of a PDCCH monitoring group (PMG) that also includes at least a first UE. In some embodiments, the first UE can be a higher-complexity UE and the second UE can be a lower- complexity UE. The exemplary method can also include the operations of block 1160, where the second UE can receive one of the following from the first UE via SL communications: decoded content of a DCI intended for the second UE that was detected by the first UE, or an indication of the detected DCFs location in a first portion of a PDCCH SS monitored by the first UE but not the second UE.

In some embodiments, the first UE and the second UE are within a coverage area of a first DL beam associated with the cell. In such embodiments, the exemplary method can also include the operations of blocks 1110-1120. In block 1110, the second UE can measure radio quality of reference signals associated with a plurality of DL beams associated with the cell, including the first DL beam. In block 1120, the second UE can report measured radio quality for at least the first DL beam to the network node. In various embodiments, the radio quality can be measured according to one or more of the following metrics: RSRP, RSRQ, SINR, RSSI, channel occupancy, LBT failures, and CCA failures.

In some of these embodiments, the exemplary method can also include the operations of block 1115, where the second UE can select the first DL beam as a preferred beam based on one or more of the following criteria: measured radio quality above a predetermined threshold; maximum measured radio quality among the plurality of beams; and measured radio quality according to at least two different metrics. The report of the measured radio quality for the first DL beam (e.g., in block 1120) can be based on the selection of the first DL beam as a preferred beam (e.g., in block 1115).

In some embodiments, the exemplary method can also include the operations of block 1125, where the second UE can receive, from the network node, a configuration of the PMG. The PMG configuration can include indication of respective portions of a PDCCH SS that are assigned to respective UEs in the PMG, and/or indication of a resource pool for SL communications among UEs in the PMG. For example, monitoring PDCCH transmissions can be performed by the second UE (e.g., in block 1150) in the portion of the SS assigned to the second UE.

In some of these embodiments, the respective portions of the PDCCH SS differ from each other in one or more of the following aspects: search regions (SRs) in time and frequency; DCI sizes; DCI types; RNTI types; and required number of blind decodings. In some of these embodiments, the SRs for the first UE and the second UE are non-overlapping in time and frequency. An example is shown in Figure 9.

In some embodiments, the configuration (e.g., received in block 1125) can also include a value of an added delay between a received DCI and a signal or channel scheduled via the received DCI. The added delay can be related to SL communications (e.g., as performed in block 1160). For example, the added delay can be a value that is added to one or more of K0, Kl, and K2 values determined from parameters included in various DCI.

In some embodiments, the configuration (e.g., received in block 1125) can also include identifiers of UEs assigned to the PMG, e.g., by the network node. In other embodiments, the exemplary method can also include the operations of block 1130, where the second UE can receive, from the first UE via SL communications, identifiers of UEs assigned to the PMG.

In other embodiments, the configuration for the PMG (e.g., received in block 1125) can also indicate that the PMG is associated with one or more of the following: the cell, a DL beam, a carrier frequency, and a BWP. In such embodiments, the exemplary method can also include the operations of blocks 1140-1145. In block 1140, the second UE can receive, from the network node, a first assignment of the second UE to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG. In block 1145, the second UE can determine a second assignment of the second UE to the PMG based on the first assignment (e.g., received in block 1140) and the configuration (e.g., received in block 1125).

In addition, Figure 12 shows an exemplary method (e.g., procedure) for transmitting DCI to a plurality of UEs operating in a cell of a wireless network, according to various embodiments of the present disclosure. The exemplary method can be performed by a network node (e.g, base station, eNB, gNB, ng-eNB, etc., or component thereof) serving the cell in the wireless network (e.g, E-UTRAN, NG-RAN), such as network nodes described elsewhere herein.

The exemplary method can include the operations of block 1230, where the network node can transmit a configuration for a PDCCH monitoring group (PMG) that includes at least a first UE and a second UE. For example, the configuration can be broadcast in the cell such that it can be received by all UEs comprising the PMG, or it can be transmitted individually (e.g., by unicast signaling) to respective UEs comprising the PMG. The exemplary method can also include the operations of block 1250, where the network node can transmit DCI intended for the second UE in a first portion of a PDCCH SS monitored by the first UE but not the second UE, in accordance with the PMG configuration (e.g., transmitted in block 1230).

In some embodiments, transmitting the DCI in block 1250 can include the operations of either sub-block 1251 or sub-block 1252. In sub-block 1251, the network node can scramble a CRC associated with the DCI based on an RNTI associated with the second UE. In sub-block 1252, the network node can include information associated with the second UE comprised in the DCI (and thus forming content of the DCI), and scramble the CRC associated with the DCI based on a RNTI associated with the first UE.

In some embodiments, the configuration (e.g., transmitted in block 1230) can include indication of respective portions of a PDCCH SS that are assigned to respective UEs in the PMG, and/or indication of a resource pool for SL communications among UEs in the PMG. In some of these embodiments, the respective portions of the PDCCH SS differ from each other in one or more of the following aspects: SRs in time and frequency; DCI sizes; DCI types; RNTI types; and required number of blind decodings. In some of these embodiments, the SRs regions for the first UE and the second UE are non-overlapping in time and frequency.

In some embodiments, the configuration (e.g., transmitted in block 1230) can also include a value of an added delay between a received DCI and a signal or channel scheduled via the received DCI. The added delay can be related to the UE forwarding of DCI via SL communications (e.g., as discussed above in relation to Figures 10-11). For example, the added delay can be a value that is added to one or more of K0, Kl, and K2 values determined from parameters included in various DCI.

In some embodiments, the configuration (e.g., transmitted in block 1230) can also include identifiers of UEs assigned to the PMG. In other embodiments, the configuration can also indicate that the PMG is associated with one or more of the following: the cell, a DL beam, a carrier frequency, and a BWP. In such embodiments, the exemplary method can also include the operations of block 1240, the network node can transmit, to the first and second UEs, respective assignments of the first and second UEs to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG. In this manner, the first and second UEs can determine their respective assignments to the PMG based on the assignments transmitted in block 1240 and the configuration transmitted in block 1230.

In some embodiments, the exemplary method can also include the operations of blocks 1210-1225. In block 1210, the network node can transmit a plurality of DL beams associated with the cell, including a first DL beam. In block 1215, the network node can receive, from the first and second UEs, reports of measured radio quality for at least the first DL beam. In various embodiments, the radio quality can be measured according to one or more of the following metrics: RSRP, RSRQ, SINR, RSSI, channel occupancy, LBT failures, and CCA failures. The inclusion of the reports for the first DL beam can indicate that beam is preferred by the first and second UEs according to some criteria.

In block 1220, the network node can, based on the reports, determine that the first and second UEs are in a coverage area of the first DL beam. In block 1225, the network node can assign the first and second UEs to the PMG based on the determination in block 1220. Furthermore, the PMG configuration transmitted to the UEs in block 1230 and/or the respective assignments to the PMG transmitted to the UEs in block 1240 can be based on the assignments made in block 1225.

Although various embodiments are described above in terms of methods, techniques, and/or procedures, the person of ordinary skill will readily comprehend that such methods, techniques, and/or procedures can be embodied by various combinations of hardware and software in various systems, communication devices, computing devices, control devices, apparatuses, non-transitory computer-readable media, computer program products, etc.

Figure 13 shows a block diagram of an exemplary wireless device or user equipment (UE) 1300 (hereinafter referred to as “UE 1300”) according to various embodiments of the present disclosure, including those described above with reference to other figures. For example, UE 1300 can be configured by execution of instructions, stored on a computer-readable medium, to perform operations corresponding to one or more of the exemplary methods described herein.

UE 1300 can include a processor 1310 (also referred to as “processing circuitry”) that can be operably connected to a program memory 1320 and/or a data memory 1330 via a bus 1370 that can comprise parallel address and data buses, serial ports, or other methods and/or structures known to those of ordinary skill in the art. Program memory 1320 can store software code, programs, and/or instructions (collectively shown as computer program product 1321 in Figure 13) that, when executed by processor 1310, can configure and/or facilitate UE 1300 to perform various operations, including operations corresponding to various exemplary methods described herein. As part of or in addition to such operations, execution of such instructions can configure and/or facilitate UE 1300 to communicate using one or more wired or wireless communication protocols, including one or more wireless communication protocols standardized by 3GPP, 3GPP2, or IEEE, such as those commonly known as 5G/NR, LTE, LTE-A, UMTS, HSPA, GSM, GPRS, EDGE, lxRTT, CDMA2000, 802.11 WiFi, HDMI, USB, Firewire, etc., or any other current or future protocols that can be utilized in conjunction with radio transceiver 1340, user interface 1350, and/or control interface 1360.

As another example, processor 1310 can execute program code stored in program memory 1320 that corresponds to MAC, RLC, PDCP, and RRC layer protocols standardized by 3GPP ( e.g for NR and/or LTE). As a further example, processor 1310 can execute program code stored in program memory 1320 that, together with radio transceiver 1340, implements corresponding PHY layer protocols, such as Orthogonal Frequency Division Multiplexing (OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), and Single-Carrier Frequency Division Multiple Access (SC-FDMA). As another example, processor 1310 can execute program code stored in program memory 1320 that, together with radio transceiver 1340, implements device-to-device (D2D) communications with other compatible devices and/or UEs.

Program memory 1320 can also include software code executed by processor 1310 to control the functions of UE 1300, including configuring and controlling various components such as radio transceiver 1340, user interface 1350, and/or control interface 1360. Program memory 1320 can also comprise one or more application programs and/or modules comprising computer- executable instructions embodying any of the exemplary methods described herein. Such software code can be specified or written using any known or future developed programming language, such as e.g., Java, C++, C, Objective C, HTML, XHTML, machine code, and Assembler, as long as the desired functionality, e.g, as defined by the implemented method steps, is preserved. In addition, or as an alternative, program memory 1320 can comprise an external storage arrangement (not shown) remote from UE 1300, from which the instructions can be downloaded into program memory 1320 located within or removably coupled to UE 1300, so as to enable execution of such instructions.

Data memory 1330 can include memory area for processor 1310 to store variables used in protocols, configuration, control, and other functions of UE 1300, including operations corresponding to, or comprising, any of the exemplary methods described herein. Moreover, program memory 1320 and/or data memory 1330 can include non-volatile memory (e.g, flash memory), volatile memory (e.g, static or dynamic RAM), or a combination thereof. Furthermore, data memory 1330 can comprise a memory slot by which removable memory cards in one or more formats (e.g, SD Card, Memory Stick, Compact Flash, etc.) can be inserted and removed.

Persons of ordinary skill will recognize that processor 1310 can include multiple individual processors (including, e.g, multi-core processors), each of which implements a portion of the functionality described above. In such cases, multiple individual processors can be commonly connected to program memory 1320 and data memory 1330 or individually connected to multiple individual program memories and or data memories. More generally, persons of ordinary skill in the art will recognize that various protocols and other functions of UE 1300 can be implemented in many different computer arrangements comprising different combinations of hardware and software including, but not limited to, application processors, signal processors, general-purpose processors, multi-core processors, ASICs, fixed and/or programmable digital circuitry, analog baseband circuitry, radio-frequency circuitry, software, firmware, and middleware.

Radio transceiver 1340 can include radio-frequency transmitter and/or receiver functionality that facilitates the UE 1300 to communicate with other equipment supporting like wireless communication standards and/or protocols. In some exemplary embodiments, the radio transceiver 1340 includes one or more transmitters and one or more receivers that enable UE 1300 to communicate according to various protocols and/or methods proposed for standardization by 3GPP and/or other standards bodies. For example, such functionality can operate cooperatively with processor 1310 to implement a PHY layer based on OFDM, OFDMA, and/or SC-FDMA technologies, such as described herein with respect to other figures.

In some exemplary embodiments, radio transceiver 1340 includes one or more transmitters and one or more receivers that can facilitate the UE 1300 to communicate with various LTE, LTE- Advanced (LTE- A), and/or NR networks according to standards promulgated by 3 GPP. In some exemplary embodiments of the present disclosure, the radio transceiver 1340 includes circuitry, firmware, etc. necessary for the UE 1300 to communicate with various NR, NR-U, LTE, LTE- A, LTE-LAA, UMTS, and/or GSM/EDGE networks, also according to 3GPP standards. In some embodiments, radio transceiver 1340 can include circuitry supporting D2D communications between UE 1300 and other compatible devices.

In some embodiments, radio transceiver 1340 includes circuitry, firmware, etc. necessary for the UE 1300 to communicate with various CDMA2000 networks, according to 3GPP2 standards. In some embodiments, the radio transceiver 1340 can be capable of communicating using radio technologies that operate in unlicensed frequency bands, such as IEEE 802.11 WiFi that operates using frequencies in the regions of 2.4, 5.6, and/or 60 GHz. In some embodiments, radio transceiver 1340 can include a transceiver that is capable of wired communication, such as by using IEEE 802.3 Ethernet technology. The functionality particular to each of these embodiments can be coupled with and/or controlled by other circuitry in the UE 1300, such as the processor 1310 executing program code stored in program memory 1320 in conjunction with, and/or supported by, data memory 1330.

User interface 1350 can take various forms depending on the particular embodiment of UE 1300, or can be absent from UE 1300 entirely. In some embodiments, user interface 1350 can comprise a microphone, a loudspeaker, slidable buttons, depressible buttons, a display, a touchscreen display, a mechanical or virtual keypad, a mechanical or virtual keyboard, and/or any other user-interface features commonly found on mobile phones. In other embodiments, the UE 1300 can comprise a tablet computing device including a larger touchscreen display. In such embodiments, one or more of the mechanical features of the user interface 1350 can be replaced by comparable or functionally equivalent virtual user interface features ( e.g ., virtual keypad, virtual buttons, etc.) implemented using the touchscreen display, as familiar to persons of ordinary skill in the art. In other embodiments, the UE 1300 can be a digital computing device, such as a laptop computer, desktop computer, workstation, etc. that comprises a mechanical keyboard that can be integrated, detached, or detachable depending on the particular exemplary embodiment. Such a digital computing device can also comprise a touch screen display. Many exemplary embodiments of the UE 1300 having a touch screen display are capable of receiving user inputs, such as inputs related to exemplary methods described herein or otherwise known to persons of ordinary skill.

In some embodiments, UE 1300 can include an orientation sensor, which can be used in various ways by features and functions of UE 1300. For example, the UE 1300 can use outputs of the orientation sensor to determine when a user has changed the physical orientation of the UE 1300’s touch screen display. An indication signal from the orientation sensor can be available to any application program executing on the UE 1300, such that an application program can change the orientation of a screen display ( e.g from portrait to landscape) automatically when the indication signal indicates an approximate 130-degree change in physical orientation of the device. In this exemplary manner, the application program can maintain the screen display in a manner that is readable by the user, regardless of the physical orientation of the device. In addition, the output of the orientation sensor can be used in conjunction with various exemplary embodiments of the present disclosure.

A control interface 1360 of the UE 1300 can take various forms depending on the particular exemplary embodiment of UE 1300 and of the particular interface requirements of other devices that the UE 1300 is intended to communicate with and/or control. For example, the control interface 1360 can comprise an RS-232 interface, aUSB interface, an HDMI interface, a Bluetooth interface, an IEEE (“Firewire”) interface, an I²C interface, a PCMCIA interface, or the like. In some exemplary embodiments of the present disclosure, control interface 1360 can comprise an IEEE 802.3 Ethernet interface such as described above. In some exemplary embodiments of the present disclosure, the control interface 1360 can comprise analog interface circuitry including, for example, one or more digital-to-analog converters (DACs) and/or analog-to-digital converters (ADCs).

Persons of ordinary skill in the art can recognize the above list of features, interfaces, and radio-frequency communication standards is merely exemplary, and not limiting to the scope of the present disclosure. In other words, the UE 1300 can comprise more functionality than is shown in Figure 13 including, for example, a video and/or still-image camera, microphone, media player and/or recorder, etc. Moreover, radio transceiver 1340 can include circuitry necessary to communicate using additional radio-frequency communication standards including Bluetooth, GPS, and/or others. Moreover, the processor 1310 can execute software code stored in the program memory 1320 to control such additional functionality. For example, directional velocity and/or position estimates output from a GPS receiver can be available to any application program executing on the UE 1300, including any program code corresponding to and/or embodying any exemplary embodiments ( e.g ., of methods) described herein.

Figure 14 shows a block diagram of an exemplary network node 1400 according to various embodiments of the present disclosure, including those described above with reference to other figures. For example, exemplary network node 1400 can be configured by execution of instructions, stored on a computer-readable medium, to perform operations corresponding to one or more of the exemplary methods described herein. In some exemplary embodiments, network node 1400 can comprise a base station, eNB, gNB, or one or more components thereof. For example, network node 1400 can be configured as a central unit (CU) and one or more distributed units (DUs) according to NR gNB architectures specified by 3GPP. More generally, the functionally of network node 1400 can be distributed across various physical devices and/or functional units, modules, etc.

Network node 1400 can include processor 1410 (also referred to as “processing circuitry”) that is operably connected to program memory 1420 and data memory 1430 via bus 1470, which can include parallel address and data buses, serial ports, or other methods and/or structures known to those of ordinary skill in the art.

Program memory 1420 can store software code, programs, and/or instructions (collectively shown as computer program product 1421 in Figure 14) that, when executed by processor 1410, can configure and/or facilitate network node 1400 to perform various operations, including operations corresponding to various exemplary methods described herein. As part of and/or in addition to such operations, program memory 1420 can also include software code executed by processor 1410 that can configure and/or facilitate network node 1400 to communicate with one or more other UEs or network nodes using other protocols or protocol layers, such as one or more of the PHY, MAC, RLC, PDCP, and RRC layer protocols standardized by 3GPP for LTE, LTE- A, and/or NR, or any other higher-layer (e.g., NAS) protocols utilized in conjunction with radio network interface 1440 and/or core network interface 1450. By way of example, core network interface 1450 can comprise the SI or NG interface and radio network interface 1440 can comprise the Uu interface, as standardized by 3 GPP. Program memory 1420 can also comprise software code executed by processor 1410 to control the functions of network node 1400, including configuring and controlling various components such as radio network interface 1440 and core network interface 1450.

Data memory 1430 can comprise memory area for processor 1410 to store variables used in protocols, configuration, control, and other functions of network node 1400. As such, program memory 1420 and data memory 1430 can comprise non-volatile memory (e.g, flash memory, hard disk, etc.), volatile memory (e.g, static or dynamic RAM), network-based (e.g, “cloud”) storage, or a combination thereof. Persons of ordinary skill in the art will recognize that processor 1410 can include multiple individual processors (not shown), each of which implements a portion of the functionality described above. In such case, multiple individual processors may be commonly connected to program memory 1420 and data memory 1430 or individually connected to multiple individual program memories and/or data memories. More generally, persons of ordinary skill will recognize that various protocols and other functions of network node 1400 may be implemented in many different combinations of hardware and software including, but not limited to, application processors, signal processors, general-purpose processors, multi-core processors, ASICs, fixed digital circuitry, programmable digital circuitry, analog baseband circuitry, radio-frequency circuitry, software, firmware, and middleware.

Radio network interface 1440 can comprise transmitters, receivers, signal processors, ASICs, antennas, beamforming units, and other circuitry that enables network node 1400 to communicate with other equipment such as, in some embodiments, a plurality of compatible user equipment (UE). In some embodiments, interface 1440 can also enable network node 1400 to communicate with compatible satellites of a satellite communication network. In some exemplary embodiments, radio network interface 1440 can comprise various protocols or protocol layers, such as the PHY, MAC, RLC, PDCP, and/or RRC layer protocols standardized by 3GPP for LTE, LTE-A, LTE-LAA, NR, NR-U, etc. ; improvements thereto such as described herein above; or any other higher-layer protocols utilized in conjunction with radio network interface 1440. According to further exemplary embodiments of the present disclosure, the radio network interface 1440 can comprise a PHY layer based on OFDM, OFDMA, and/or SC-FDMA technologies. In some embodiments, the functionality of such a PHY layer can be provided cooperatively by radio network interface 1440 and processor 1410 (including program code in memory 1420).

Core network interface 1450 can comprise transmitters, receivers, and other circuitry that enables network node 1400 to communicate with other equipment in a core network such as, in some embodiments, circuit-switched (CS) and/or packet-switched Core (PS) networks. In some embodiments, core network interface 1450 can comprise the SI interface standardized by 3GPP. In some embodiments, core network interface 1450 can comprise the NG interface standardized by 3GPP. In some exemplary embodiments, core network interface 1450 can comprise one or more interfaces to one or more AMFs, SMFs, SGWs, MMEs, SGSNs, GGSNs, and other physical devices that comprise functionality found in GERAN, UTRAN, EPC, 5GC, and CDMA2000 core networks that are known to persons of ordinary skill in the art. In some embodiments, these one or more interfaces may be multiplexed together on a single physical interface. In some embodiments, lower layers of core network interface 1450 can comprise one or more of asynchronous transfer mode (ATM), Internet Protocol (IP)-over-Ethemet, SDH over optical fiber, T1/E1/PDH over a copper wire, microwave radio, or other wired or wireless transmission technologies known to those of ordinary skill in the art.

In some embodiments, network node 1400 can include hardware and/or software that configures and/or facilitates network node 1400 to communicate with other network nodes in a RAN, such as with other eNBs, gNBs, ng-eNBs, en-gNBs, I B nodes, etc. Such hardware and/or software can be part of radio network interface 1440 and/or core network interface 1450, or it can be a separate functional unit (not shown). For example, such hardware and/or software can configure and/or facilitate network node 1400 to communicate with other RAN nodes via the X2 or Xn interfaces, as standardized by 3 GPP.

OA&M interface 1460 can comprise transmitters, receivers, and other circuitry that enables network node 1400 to communicate with external networks, computers, databases, and the like for purposes of operations, administration, and maintenance of network node 1400 or other network equipment operably connected thereto. Lower layers of OA&M interface 1460 can comprise one or more of asynchronous transfer mode (ATM), Internet Protocol (IP)-over- Ethemet, SDH over optical fiber, T1/E1/PDH over a copper wire, microwave radio, or other wired or wireless transmission technologies known to those of ordinary skill in the art. Moreover, in some embodiments, one or more of radio network interface 1440, core network interface 1450, and OA&M interface 1460 may be multiplexed together on a single physical interface, such as the examples listed above.

Figure 15 is a block diagram of an exemplary communication network configured to provide over-the-top (OTT) data services between a host computer and a user equipment (UE), according to one or more exemplary embodiments of the present disclosure. UE 1510 can communicate with radio access network (RAN) 1530 over radio interface 1520, which can be based on protocols described above including, e.g., LTE, LTE-A, and 5G/NR. For example, UE 1510 can be configured and/or arranged as shown in other figures discussed above.

RAN 1530 can include one or more terrestrial network nodes (e.g, base stations, eNBs, gNBs, controllers, etc.) operable in licensed spectrum bands, as well one or more network nodes operable in unlicensed spectrum (using, e.g, LAA or NR-U technology), such as a 2.4-GHz band and/or a 5-GHz band. In such cases, the network nodes comprising RAN 1530 can cooperatively operate using licensed and unlicensed spectrum. In some embodiments, RAN 1530 can include, or be capable of communication with, one or more satellites comprising a satellite access network.

RAN 1530 can further communicate with core network 1540 according to various protocols and interfaces described above. For example, one or more apparatus (e.g, base stations, eNBs, gNBs, etc.) comprising RAN 1530 can communicate to core network 1540 via core network interface 1550 described above. In some exemplary embodiments, RAN 1530 and core network 1540 can be configured and/or arranged as shown in other figures discussed above. For example, eNBs comprising an E-UTRAN 1530 can communicate with an EPC core network 1540 via an SI interface. As another example, gNBs and ng-eNBs comprising an NG-RAN 1530 can communicate with a 5GC core network 1530 via an NG interface.

Core network 1540 can further communicate with an external packet data network, illustrated in Figure 15 as Internet 1550, according to various protocols and interfaces known to persons of ordinary skill in the art. Many other devices and/or networks can also connect to and communicate via Internet 1550, such as exemplary host computer 1560. In some exemplary embodiments, host computer 1560 can communicate with UE 1510 using Internet 1550, core network 1540, and RAN 1530 as intermediaries. Host computer 1560 can be a server ( e.g ., an application server) under ownership and/or control of a service provider. Host computer 1560 can be operated by the OTT service provider or by another entity on the service provider’s behalf.

For example, host computer 1560 can provide an over-the-top (OTT) packet data service to UE 1510 using facilities of core network 1540 and RAN 1530, which can be unaware of the routing of an outgoing/incoming communication to/from host computer 1560. Similarly, host computer 1560 can be unaware of routing of a transmission from the host computer to the UE, e.g., the routing of the transmission through RAN 1530. Various OTT services can be provided using the exemplary configuration shown in Figure 15 including, e.g, streaming (unidirectional) audio and/or video from host computer to UE, interactive (bidirectional) audio and/or video between host computer and UE, interactive messaging or social communication, interactive virtual or augmented reality, etc.

The exemplary network shown in Figure 15 can also include measurement procedures and/or sensors that monitor network performance metrics including data rate, latency and other factors that are improved by exemplary embodiments disclosed herein. The exemplary network can also include functionality for reconfiguring the link between the endpoints (e.g, host computer and UE) in response to variations in the measurement results. Such procedures and functionalities are known and practiced; if the network hides or abstracts the radio interface from the OTT service provider, measurements can be facilitated by proprietary signaling between the UE and the host computer.

The exemplary embodiments described herein provide a flexible mechanism to facilitate splitting a DCI search space such that a lower-complexity UE can be assigned only a small subset of the search space that results in a low DCI blind decoding complexity or load. At the same time, a higher-complexity UE (e.g., with larger battery and/or more processing capabilities) can be assigned to perform blind decoding on behalf of lower-complexity UE(s) in the same PDCCH monitoring group and can forward any decoded DCI(s) that is(are) intended for these lower-complexity UE(s). In this manner, the complexity and energy consumption associated with DCI blind decoding is decreased for the lower-complexity UEs. When used in NRUEs ( e.g ., UE 1510) and gNBs ( e.g ., gNBs comprising RAN 1530), exemplary embodiments described herein can provide various improvements, benefits, and/or advantages in terms of reduced UE energy consumption. This reduction can increase the use of data services by allowing the UE to allocate a greater portion of its stored energy for data services (e.g., eMBB) while in connected state. Consequently, this increases the benefits and/or value of such data services to end users and OTT service providers.

The foregoing merely illustrates the principles of the disclosure. Various modifications and alterations to the described embodiments will be apparent to those skilled in the art in view of the teachings herein. It will thus be appreciated that those skilled in the art will be able to devise numerous systems, arrangements, and procedures that, although not explicitly shown or described herein, embody the principles of the disclosure and can be thus within the spirit and scope of the disclosure. Various exemplary embodiments can be used together with one another, as well as interchangeably therewith, as should be understood by those having ordinary skill in the art.

The term unit, as used herein, can have conventional meaning in the field of electronics, electrical devices and/or electronic devices and can include, for example, electrical and/or electronic circuitry, devices, modules, processors, memories, logic solid state and/or discrete devices, computer programs or instructions for carrying out respective tasks, procedures, computations, outputs, and/or displaying functions, and so on, as such as those that are described herein.

Any appropriate steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more virtual apparatuses. Each virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include Digital Signal Processor (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as Read Only Memory (ROM), Random Access Memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions according one or more embodiments of the present disclosure. As described herein, device and/or apparatus can be represented by a semiconductor chip, a chipset, or a (hardware) module comprising such chip or chipset; this, however, does not exclude the possibility that a functionality of a device or apparatus, instead of being hardware implemented, be implemented as a software module such as a computer program or a computer program product comprising executable software code portions for execution or being run on a processor. Furthermore, functionality of a device or apparatus can be implemented by any combination of hardware and software. A device or apparatus can also be regarded as an assembly of multiple devices and/or apparatuses, whether functionally in cooperation with or independently of each other. Moreover, devices and apparatuses can be implemented in a distributed fashion throughout a system, so long as the functionality of the device or apparatus is preserved. Such and similar principles are considered as known to a skilled person.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms used herein should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

In addition, certain terms used in the present disclosure, including the specification and drawings, can be used synonymously in certain instances ( e.g “data” and “information”). It should be understood, that although these terms (and/or other terms that can be synonymous to one another) can be used synonymously herein, there can be instances when such words can be intended to not be used synonymously. Further, to the extent that the prior art knowledge has not been explicitly incorporated by reference herein above, it is explicitly incorporated herein in its entirety. All publications referenced are incorporated herein by reference in their entireties.

Embodiments of the techniques and apparatus described herein also include, but are not limited to, the following enumerated examples:

A1. A method for a first user equipment (UE) to receive downlink control information (DCI) from a network node serving a cell in a wireless network, the method comprising: monitoring physical downlink control channel (PDCCH) transmissions by the network node for DCI intended for UEs within a PDCCH monitoring group (PMG) that includes the first UE and at least a second UE; and upon detecting a DCI intended for the second UE, forwarding one of the following to the second UE via sidelink (SL) communications: decoded contents of the detected DCI, or an indication of the detected DCFs location in a PDCCH search space (SS).

A2. The method of embodiment Al, further comprising detecting the DCI intended for the second UE based on one of the following: descrambling a cyclic redundancy check (CRC) associated with the DCI based on a radio network temporary identifier (RNTI) associated with the second UE; or descrambling the CRC associated with the DCI based on a RNTI associated with the first

UE, and detecting information associated with the second UE in the contents of the DCI.

A3. The method of any of embodiments A1-A2, further comprising receiving, from the network node, a configuration of the PMG, wherein the configuration includes one or more of the following: indication of respective portions of a PDCCH search space (SS) that are assigned to respective UEs in the PMG; and indication of a resource pool for SL communications among UEs in the PMG.

A4. The method of embodiment A3, wherein: the configuration also includes a value of an added delay between a received DCI and a signal or channel scheduled via the received DCI; and the added delay is related to the forwarding via SL communications.

A5. The method of any of embodiments A3-A4, wherein the respective portions of the PDCCH SS differ from each other in one or more of the following aspects: search regions (SRs) in time and frequency; DCI sizes; DCI types; radio network temporary identifier (RNTI) types; and required number of blind decodings.

A6. The method of embodiment A5, wherein the SRs regions for the first UE and the second UE are non-overlapping in time and frequency.

A7. The method of any of embodiments A3-A6, wherein the configuration also includes identifiers of UEs assigned to the PMG.

A8. The method of any of embodiments A3-A6, further comprising: determining identifiers for UEs assigned to the PMG; and transmitting the determined identifiers to the UEs assigned to the PMG via SL communications.

A9. The method of any of embodiments A3-A6, wherein: the configuration for the PMG also indicates that the PMG is associated with one or more of the following: the cell, a downlink (DL) beam, a carrier frequency, and a bandwidth part (BWP); and the method further comprises: receiving, from the network node, a first assignment of the first UE to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG; and determining a second assignment of the first UE to the PMG based on the first assignment and the configuration.

A10. The method of any of embodiments A3-A9, wherein monitoring PDCCH transmissions is performed in the portion of the SS assigned to the first UE.

A11. The method of any of embodiments A1-A10, wherein the first UE and the second UE are within a coverage area of a first downlink (DL) beam associated with the cell.

A12. The method of embodiment All, further comprising: measuring radio quality of reference signals associated with a plurality of DL beams associated with the cell, including the first DL beam; and reporting measured radio quality for at least the first DL beam to the network node.

A13. The method of embodiment A12, wherein the radio quality is measured according to one or more of the following metrics: reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference-plus-noise ratio (SINR), received signal strength (RSSI), channel occupancy, listen-before-talk (LBT) failures, and clear channel assessment (CCA) failures.

A14. The method of any of embodiments A12-A13, further comprising selecting the first DL beam as a preferred beam based on one or more of the following criteria: measured radio quality above a predetermined threshold; maximum measured radio quality among the plurality of beams; and measured radio quality according to at least two different metrics.

A15. The method of any of embodiments A1-A14, wherein the first UE is a higher-complexity UE and the second EE is a lower-complexity UE

Bl. A method for a second user equipment (UE) to receive downlink control information (DCI) from a network node serving a cell in a wireless network, the method comprising: monitoring physical downlink control channel (PDCCH) transmissions by the network node for DCI intended for the second UE, wherein the second UE is part of a PDCCH monitoring group (PMG) that includes at least a first UE; and receiving one of the following from the first UE via sidelink (SL) communications: decoded contents of a DCI intended for the second UE that was detected by the first UE, or an indication of the detected DCFs location in a first portion of a PDCCH search space (SS) monitored by the first UE but not the second UE.

B2. The method of embodiment Bl, further comprising receiving, from the network node, a configuration of the PMG, wherein the configuration includes one or more of the following: indication of respective portions of a PDCCH SS that are assigned to respective UEs in the PMG; and indication of a resource pool for SL communications among UEs in the PMG.

B3. The method of embodiment B2, wherein: the configuration also includes a value of an added delay between a received DCI and a signal or channel scheduled via the received DCI; and the added delay is related to the receiving via SL communications.

B4. The method of any of embodiments B2-B3, wherein the respective portions of the PDCCH SS differ from each other in one or more of the following aspects: search regions (SRs) in time and frequency; DCI sizes; DCI types; radio network temporary identifier (RNTI) types; and required number of blind decodings.

B5. The method of embodiment B4, wherein the SRs for the first UE and the second UE are non-overlapping in time and frequency. B6. The method of any of embodiments B2-B5, wherein the configuration also includes identifiers of UEs assigned to the PMG.

B7. The method of any of embodiments B2-B5, further comprising receiving, from the first UE via SL communications, identifiers of UEs assigned to the PMG.

B8. The method of any of embodiments B2-B5, wherein: the configuration for the PMG also indicates that the PMG is associated with one or more of the following: the cell, a downlink (DL) beam, a carrier frequency, and a bandwidth part (BWP); and the method further comprises: receiving, from the network node, a first assignment of the second UE to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG; and determining a second assignment of the second UE to the PMG based on the first assignment and the configuration.

B9. The method of any of embodiments B2-B8, wherein monitoring PDCCH transmissions is performed in the portion of the SS assigned to the second UE.

BIO. The method of any of embodiments B1-B9, wherein the first UE and the second UE are within a coverage area of a first downlink (DL) beam associated with the cell.

B11. The method of embodiment BIO, further comprising: measuring radio quality of reference signals associated with a plurality of DL beams associated with the cell, including the first DL beam; and reporting measured radio quality for at least the first DL beam to the network node.

B12. The method of embodiment B11, wherein the radio quality is measured according to one or more of the following metrics: reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference-plus-noise ratio (SINR), received signal strength (RSSI), channel occupancy, listen-before-talk (LBT) failures, and clear channel assessment (CCA) failures. B13. The method of any of embodiments B11-B12, further comprising selecting the first DL beam as a preferred beam based on one or more of the following criteria: measured radio quality above a predetermined threshold; maximum measured radio quality among the plurality of beams; and measured radio quality according to at least two different metrics.

B14. The method of any of embodiments B1-B13, wherein the second UE is a lower- complexity UE and the first EE is a higher-complexity UE

Cl . A method for a network node, in a wireless network, to transmit downlink control information (DCI) to a plurality of UEs operating in a cell served by the network node, the method comprising: transmitting a configuration for a physical downlink control channel (PDCCH) monitoring group (PMG) that includes at least a first UE and a second UE; and transmitting DCI intended for the second UE in a first portion of a PDCCH search space (SS) monitored by the first UE but not the second UE, in accordance with the PMG configuration.

C2. The method of embodiment Cl, wherein transmitting the DCI intended for the second comprises one of the following: scrambling a cyclic redundancy check (CRC) associated with the DCI based on a radio network temporary identifier (RNTI) associated with the second UE; or including information associated with the second UE in the contents of the DCI, and scrambling the CRC associated with the DCI based on a RNTI associated with the first UE.

C3. The method of any of embodiments C1-C2, wherein the configuration includes one or more of the following: indication of respective portions of a PDCCH search space (SS) that are assigned to respective UEs in the PMG; and indication of a resource pool for SL communications among UEs in the PMG.

C4. The method of embodiment C3, wherein: the configuration also includes a value of an added delay between a received DCI and a signal or channel scheduled via the received DCI; and the added delay is related to UE forwarding of DCI via SL communications.

C5. The method of any of embodiments C3-C4, wherein the respective portions of the PDCCH SS differ from each other in one or more of the following aspects: search regions (SRs) in time and frequency; DCI sizes; DCI types; radio network temporary identifier (RNTI) types; and required number of blind decodings.

C6. The method of embodiment A5, wherein the SRs for the first UE and the second UE are non-overlapping in time and frequency.

C7. The method of any of embodiments C3-C6, wherein the configuration also includes identifiers of UEs assigned to the PMG.

C8. The method of any of embodiments C3-C6, wherein: the configuration for the PMG also indicates that the PMG is associated with one or more of the following: the cell, a downlink (DL) beam, a carrier frequency, and a bandwidth part (BWP); and the method further comprises transmitting, to the first and second UEs, respective assignments of the first and second UEs to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG.

C9. The method of any of embodiments C1-C8, further comprising: transmitting a plurality of downlink (DL) beams associated with the cell, including a first DL beam; receiving, from the first and second UEs, reports of measured radio quality for at least the first DL beam; based on the reports, determining that the first and second UEs are in a coverage area of the first DL beam; and assigning the first and second UEs to the PMG based on the determination.

CIO. The method of embodiment C9, wherein the radio quality is measured according to one or more of the following metrics: reference signal received power (RSRP), reference signal received quality (RSRQ), signal-to-interference-plus-noise ratio (SINR), received signal strength (RSSI), channel occupancy, listen-before-talk (LBT) failures, and clear channel assessment (CCA) failures. Cl 1. The method of any of embodiments Cl -CIO, wherein the second UE is a lower- complexity UE and the first UE is a higher-complexity UE.

D1. A first user equipment (UE) configured to receive downlink control information (DCI) from a network node serving a cell in a wireless network, the first UE comprising: radio transceiver circuitry configured to communicate with the network node and at least a second UE; and processing circuitry operably coupled to the radio transceiver circuitry, whereby the processing circuitry and the radio transceiver circuitry are configured to perform operations corresponding to the methods of any of embodiments A1-A14.

D2. A first user equipment (UE) configured to receive downlink control information (DCI) from a network node serving a cell in a wireless network, the first UE being arranged to perform operations corresponding to the methods of any of embodiments A1-A14.

D3. A non-transitory, computer-readable medium storing computer-executable instructions that, when executed by processing circuitry of a first user equipment (UE) configured to receive downlink control information (DCI) from a network node serving a cell in a wireless network, configure the first UE to perform operations corresponding to any of the methods of embodiments A1-A14.

D4. A computer program product comprising computer-executable instructions that, when executed by processing circuitry of a first user equipment (UE) configured to receive downlink control information (DCI) from a network node serving a cell in a wireless network, configure the first UE to perform operations corresponding to any of the methods of embodiments Al- A14.

El . A second user equipment (UE) configured to receive downlink control information (DCI) from a network node serving a cell in a wireless network, the second UE comprising: radio transceiver circuitry configured to communicate with the network node and at least a second UE; and processing circuitry operably coupled to the radio transceiver circuitry, whereby the processing circuitry and the radio transceiver circuitry are configured to perform operations corresponding to the methods of any of embodiments B1-B14. E2. A second user equipment (UE) configured to receive downlink control information (DCI) from a network node serving a cell in a wireless network, the second UE being arranged to perform operations corresponding to the methods of any of embodiments B1-B14.

E3. A non-transitory, computer-readable medium storing computer-executable instructions that, when executed by processing circuitry of a second user equipment (UE) configured to receive downlink control information (DCI) from a network node serving a cell in a wireless network, configure the second UE to perform operations corresponding to any of the methods of embodiments B1-B14.

E4. A computer program product comprising computer-executable instructions that, when executed by processing circuitry of a second user equipment (UE) configured to receive downlink control information (DCI) from a network node serving a cell in a wireless network, configure the second UE to perform operations corresponding to any of the methods of embodiments B1-B14.

FI. A network node configured to transmit downlink control information (DCI) to a plurality of UEs operating in a cell served by the network node in a wireless network, the network node comprising: radio network interface circuitry configured to communicate with the UEs; and processing circuitry operatively coupled to the radio network interface circuitry, whereby the processing circuitry and the radio network interface circuitry are configured to perform operations corresponding to any of the methods of embodiments Cl- C l l .

F2. A network node configured to transmit downlink control information (DCI) to a plurality of UEs operating in a cell served by the network node in a wireless network, the network node being arranged to perform operations corresponding to any of the methods of embodiments Cl- C l l .

F3. A non-transitory, computer-readable medium storing computer-executable instructions that, when executed by processing circuitry of a network node configured to transmit downlink control information (DCI) to a plurality of UEs operating in a cell served by the network node in a wireless network, configure the network node to perform operations corresponding to any of the methods of embodiments Cl -Cl 1.

F4. A computer program product comprising computer-executable instructions that, when executed by processing circuitry of a network node configured to transmit downlink control information (DCI) to a plurality of UEs operating in a cell served by the network node in a wireless network, configure the network node to perform operations corresponding to any of the methods of embodiments Cl-Cll.

Claims

1. A method for a first user equipment, UE, to receive downlink control information, DCI, from a network node serving a cell in a wireless network, the method comprising: monitoring (1050) physical downlink control channel, PDCCH, transmissions by the network node for DCI intended for UEs within a PDCCH monitoring group, PMG, that includes the first UE and at least a second UE; and upon detecting a DCI intended for the second UE, forwarding (1070) one of the following to the second UE via sidelink, SL, communications: decoded content of the detected DCI, or an indication of the detected DCFs location in a PDCCH search space, SS.

2. The method of claim 1, further comprising detecting (1060) the DCI intended for the second UE based on one of the following: descrambling (1061) a cyclic redundancy check, CRC, associated with the DCI based on a radio network temporary identifier, RNTI, associated with the second UE; or descrambling (1062) the CRC associated with the DCI based on a RNTI associated with the first UE, and detecting information associated with the second UE in the content of the DCI.

3. The method of any of claims 1-2, further comprising receiving (1025), from the network node, a configuration of the PMG, wherein the configuration includes one or more of the following: indication of respective portions of a PDCCH SS that are assigned to respective UEs in the PMG; and indication of a resource pool for SL communications among UEs in the PMG.

4. The method of claim 3, wherein: the configuration also includes a value of an added delay between a received DCI and a signal or channel scheduled via the received DCI; and the added delay is related to the forwarding via SL communications.

5. The method of any of claims 3-4, wherein the respective portions of the PDCCH SS differ from each other in one or more of the following aspects: search regions, SRs, in time and frequency; DCI sizes; DCI types; radio network temporary identifier, RNTI, types; and required number of blind decodings.

6. The method of claim 5, wherein the SRs for the first UE and the second UE are non overlapping in time and frequency.

7. The method of any of claims 3-6, wherein one of the following applies: the configuration also includes identifiers of EEs assigned to the PMG; or the method further comprises: determining (1030) identifiers for EEs assigned to the PMG; and transmitting (1035) the determined identifiers to the EEs assigned to the PMG via SL communications.

8. The method of any of claims 3-6, wherein: the configuration for the PMG also indicates that the PMG is associated with one or more of the following: the cell; a downlink, DL, beam; a carrier frequency; and a bandwidth part, BWP; and the method further comprises: receiving (1040), from the network node, a first assignment of the first EE to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG; and determining (1045) a second assignment of the first EE to the PMG based on the first assignment and the configuration.

9. The method of any of claims 3-8, wherein monitoring (1050) PDCCH transmissions is performed in the portion of the SS assigned to the first EE.

10. The method of any of claims 1-9, wherein the first EE and the second EE are within a coverage area of a first downlink, DL, beam associated with the cell.

11. The method of claim 10, further comprising: measuring (1010) radio quality of reference signals associated with a plurality of DL beams associated with the cell, including the first DL beam; and reporting (1020) measured radio quality for at least the first DL beam to the network node.

12. The method of claim 11, wherein the radio quality is measured according to one or more of the following metrics: reference signal received power, RSRP; reference signal received quality, RSRQ; signal-to-interference-plus-noise ratio, SINR; received signal strength, RSSI; channel occupancy; listen-before-talk, LBT, failures; and clear channel assessment, CCA, failures.

13. The method of any of claims 11-12, further comprising selecting (1015) the first DL beam as a preferred beam based on one or more of the following criteria: measured radio quality above a predetermined threshold; maximum measured radio quality among the plurality of beams; and measured radio quality according to at least two different metrics.

14. The method of any of claims 1-13, wherein the first UE is a higher-complexity UE and the second UE is a lower-complexity UE.

15. A method for a second user equipment, UE, to receive downlink control information, DCI, from a network node serving a cell in a wireless network, the method comprising: monitoring (1150) physical downlink control channel, PDCCH, transmissions by the network node for DCI intended for the second UE, wherein the second UE is part of a PDCCH monitoring group, PMG, that includes at least a first UE; and receiving (1160) one of the following from the first UE via sidelink, SL, communications: decoded content of a DCI intended for the second UE that was detected by the first UE, or an indication of the detected DCFs location in a first portion of a PDCCH search space, SS, monitored by the first UE.

16. The method of claim 15, further comprising receiving (1125), from the network node, a configuration of the PMG, wherein the configuration includes one or more of the following: indication of respective portions of a PDCCH SS that are assigned to respective UEs in the PMG; and indication of a resource pool for SL communications among UEs in the PMG.

17. The method of claim 16, wherein: the configuration also includes a value of an added delay between a received DCI and a signal or channel scheduled via the received DCI; and the added delay is related to the receiving via SL communications.

18. The method of any of claims 16-17, wherein the respective portions of the PDCCH SS differ from each other in one or more of the following aspects: search regions, SRs, in time and frequency; DCI sizes; DCI types; radio network temporary identifier, RNTI, types; and required number of blind decodings.

19. The method of claim 18, wherein the SRs for the first UE and the second UE are non overlapping in time and frequency.

20. The method of any of claims 16-19, wherein one of the following applies: the configuration also includes identifiers of UEs assigned to the PMG; or the method further comprises receiving (1135), from the first UE via SL communications, identifiers of UEs assigned to the PMG.

21. The method of any of claims 16-19, wherein: the configuration for the PMG also indicates that the PMG is associated with one or more of the following: the cell; a downlink, DL, beam; a carrier frequency; and a bandwidth part, BWP; and the method further comprises: receiving (1140), from the network node, a first assignment of the second UE to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG; and determining (1145) a second assignment of the second UE to the PMG based on the first assignment and the configuration.

22. The method of any of claims 16-21, wherein monitoring (1150) PDCCH transmissions is performed in the portion of the SS assigned to the second UE.

23. The method of any of claims 15-22, wherein the first UE and the second UE are within a coverage area of a first downlink, DL, beam associated with the cell.

24. The method of claim 23, further comprising: measuring (1110) radio quality of reference signals associated with a plurality of DL beams associated with the cell, including the first DL beam; and reporting (1120) measured radio quality for at least the first DL beam to the network node.

25. The method of claim 24, wherein the radio quality is measured according to one or more of the following metrics: reference signal received power, RSRP; reference signal received quality, RSRQ; signal-to-interference-plus-noise ratio, SINR; received signal strength, RSSI; channel occupancy; listen-before-talk, LBT, failures; and clear channel assessment, CCA, failures.

26. The method of any of claims 24-25, further comprising selecting (1115) the first DL beam as a preferred beam based on one or more of the following criteria: measured radio quality above a predetermined threshold; maximum measured radio quality among the plurality of beams; and measured radio quality according to at least two different metrics.

27. The method of any of claims 15-26, wherein the second UE is a lower-complexity UE and the first UE is a higher-complexity UE.

28. A method for a network node, in a wireless network, to transmit downlink control information, DCI, to a plurality of user equipment, UEs, operating in a cell served by the network node, the method comprising: transmitting (1230) a configuration for a physical downlink control channel, PDCCH, monitoring group, PMG, that includes at least a first UE and a second UE; and transmitting (1250) DCI intended for the second UE in a first portion of a PDCCH search space, SS, monitored by the first UE but not the second UE, in accordance with the PMG configuration.

29. The method of claim 28, wherein transmitting (1250) the DCI intended for the second comprises one of the following: scrambling (1251) a cyclic redundancy check, CRC, associated with the DCI based on a radio network temporary identifier, RNTI, associated with the second UE; or including (1252) information associated with the second UE in the content of the DCI, and scrambling the CRC associated with the DCI based on a RNTI associated with the first UE.

30. The method of any of claims 28-29, wherein the configuration includes one or more of the following: indication of respective portions of a PDCCH SS that are assigned to respective UEs in the PMG; and indication of a resource pool for SL communications among UEs in the PMG.

31. The method of claim 30, wherein: the configuration also includes a value of an added delay between a received DCI and a signal or channel scheduled via the received DCI; and the added delay is related to UE forwarding of DCI via SL communications.

32. The method of any of claims 30-31, wherein the respective portions of the PDCCH SS differ from each other in one or more of the following aspects: search regions, SRs, in time and frequency; DCI sizes; DCI types; radio network temporary identifier, RNTI, types; and required number of blind decodings.

33. The method of claim 32, wherein the SRs for the first UE and the second UE are non overlapping in time and frequency.

34. The method of any of claims 30-33, wherein the configuration also includes identifiers of UEs assigned to the PMG.

35. The method of any of claims 30-33, wherein: the configuration for the PMG also indicates that the PMG is associated with one or more of the following: the cell; a downlink, DL, beam; a carrier frequency; and a bandwidth part, BWP; and the method further comprises transmitting (1240), to the first and second UEs, respective assignments of the first and second UEs to one or more of the cell, the DL beam, the carrier frequency, and the BWP associated with the PMG.

36. The method of any of claims 28-35, further comprising: transmitting (1210) a plurality of downlink, DL, beams associated with the cell, including a first DL beam; receiving (1215), from the first and second UEs, reports of measured radio quality for at least the first DL beam; based on the reports, determining (1220) that the first and second UEs are in a coverage area of the first DL beam; and assigning (1225) the first and second UEs to the PMG based on the determination.

37. The method of claim 36, wherein the radio quality is measured according to one or more of the following metrics: reference signal received power, RSRP; reference signal received quality, RSRQ; signal-to-interference-plus-noise ratio, SINR; received signal strength, RSSI; channel occupancy; listen-before-talk, LBT, failures; and clear channel assessment, CCA, failures.

38. The method of any of claims 28-37, wherein the second UE is a lower-complexity UE and the first UE is a higher-complexity UE.

39. A first user equipment, UE (710, 810, 1300, 1510) configured to receive downlink control information, DCI, from a network node (300, 350, 730, 830, 1400) serving a cell (740, 840) in a wireless network (399, 1530), the first UE comprising: transceiver circuitry (1340) configured to communicate with the network node and at least a second UE; and processing circuitry (1310) operably coupled to the transceiver circuitry, whereby the processing circuitry and the radio transceiver circuitry are configured to: monitor physical downlink control channel, PDCCH, transmissions by the network node for DCI intended for UEs within a PDCCH monitoring group, PMG, that includes the first UE and at least a second UE; and upon detecting a DCI intended for the second UE, forward one of the following to the second UE via sidelink, SL, communications: decoded content of the detected DCI, or an indication of the detected DCFs location in a PDCCH search space,

SS.

40. The first UE of claim 39, wherein the processing circuitry and the radio transceiver circuitry are further configured to perform operations corresponding to any of the methods of claims 2-14.

41. A first user equipment, UE (710, 810, 1300, 1510) configured to receive downlink control information, DCI, from a network node (300, 350, 730, 830, 1400) serving a cell (740, 840) in a wireless network (399, 1530), the first UE being further configured to: monitor physical downlink control channel, PDCCH, transmissions by the network node for DCI intended for UEs within a PDCCH monitoring group, PMG, that includes the first UE and at least a second UE; and upon detecting a DCI intended for the second UE, forward one of the following to the second UE via sidelink, SL, communications: decoded content of the detected DCI, or an indication of the detected DCFs location in a PDCCH search space, SS.

42. The first UE of claim 41, being further configured to perform operations corresponding to any of the methods of claims 2-14.

43. A non-transitory, computer-readable medium (1320) storing computer-executable instructions that, when executed by processing circuitry (1310) of a first user equipment, UE (710, 810, 1300, 1510) configured to receive downlink control information, DCI, from a network node (300, 350, 730, 830, 1400) serving a cell (740, 840) in a wireless network (399, 1530), configure the first UE to perform operations corresponding to any of the methods of claims 1-14.

44. A computer program product (1321) comprising computer-executable instructions that, when executed by processing circuitry (1310) of a first user equipment, UE (710, 810, 1300, 1510) configured to receive downlink control information, DCI, from a network node (300, 350, 730, 830, 1400) serving a cell (740, 840) in a wireless network (399, 1530), configure the first UE to perform operations corresponding to any of the methods of claims 1-14.

45. A second user equipment, UE (720, 820, 1300, 1510) configured to receive downlink control information, DCI, from a network node (300, 350, 730, 830, 1400) serving a cell (740, 840) in a wireless network (399, 1530), the second UE comprising: transceiver circuitry (1340) configured to communicate with the network node and at least a second UE; and processing circuitry (1310) operably coupled to the transceiver circuitry, whereby the processing circuitry and the radio transceiver circuitry are configured to: monitor physical downlink control channel, PDCCH, transmissions by the network node for DCI intended for the second UE, wherein the second UE is part of a PDCCH monitoring group, PMG, that includes at least a first UE; and receive one of the following from the first UE via sidelink, SL, communications: decoded content of a DCI intended for the second UE that was detected by the first UE, or an indication of the detected DCFs location in a first portion of a PDCCH search space, SS, monitored by the first UE but not the second UE.

46. The second UE of claim 46, wherein the processing circuitry and the radio transceiver circuitry are further configured to perform operations corresponding to any of the methods of claims 16-27.

47. A second user equipment, UE (720, 820, 1300, 1510) configured to receive downlink control information, DCI, from a network node (300, 350, 730, 830, 1400) serving a cell (740, 840) in a wireless network (399, 1530), the second UE being further configured to: monitor physical downlink control channel, PDCCH, transmissions by the network node for DCI intended for the second UE, wherein the second UE is part of a PDCCH monitoring group, PMG, that includes at least a first UE; and receive one of the following from the first UE via sidelink, SL, communications: decoded content of a DCI intended for the second UE that was detected by the first UE, or an indication of the detected DCFs location in a first portion of a PDCCH search space, SS, monitored by the first UE but not the second UE.

48. The second UE of claim 47, being further configured to perform operations corresponding to any of the methods of claims 16-27.

49. A non-transitory, computer-readable medium (1320) storing computer-executable instructions that, when executed by processing circuitry (1310) of a second user equipment, UE (720, 820, 1300, 1510) configured to receive downlink control information, DCI, from a network node (300, 350, 730, 830, 1400) serving a cell (740, 840) in a wireless network (399, 1530), configure the second UE to perform operations corresponding to any of the methods of claims 15-27.

50. A computer program product (1321) comprising computer-executable instructions that, when executed by processing circuitry (1310) of a second user equipment, UE (720, 820, 1300, 1510) configured to receive downlink control information, DCI, from a network node (300, 350, 730, 830, 1400) serving a cell (740, 840) in a wireless network (399, 1530), configure the second UE to perform operations corresponding to any of the methods of claims 15-27.

51. A network node (300, 350, 730, 830, 1400) configured to transmit downlink control information, DCI, to user equipment, UEs (710, 720, 810, 820, 1300, 1510) in a cell (740, 840) served by the network node in a wireless network (399, 1530), the network node comprising: radio network interface circuitry (1440) configured to communicate with the UEs; and processing circuitry (1410) operatively coupled to the radio network interface circuitry, whereby the processing circuitry and the radio network interface circuitry are configured to: transmit a configuration for a physical downlink control channel, PDCCH, monitoring group, PMG, that includes at least a first UE and a second UE; and transmit DCI intended for the second UE in a first portion of a PDCCH search space, SS, monitored by the first UE but not the second UE, in accordance with the PMG configuration.

52. The network node of claim 51, wherein the processing circuitry and the radio network interface circuitry are further configured to perform operations corresponding to any of the methods of claims 29-38.

53. A network node (300, 350, 730, 830, 1400) configured to transmit downlink control information, DCI, to user equipment, UEs (710, 720, 810, 820, 1300, 1510) in a cell (740, 840) served by the network node in a wireless network (399, 1530), the network node being further configured to: transmit a configuration for a physical downlink control channel, PDCCH, monitoring group, PMG, that includes at least a first UE and a second UE; and transmit DCI intended for the second UE in a first portion of a PDCCH search space, SS, monitored by the first UE but not the second UE, in accordance with the PMG configuration.

54. The network node of claim 53, being further configured to perform operations corresponding to any of the methods of claims 29-38.

55. A non-transitory, computer-readable medium (1420) storing computer-executable instructions that, when executed by processing circuitry (1410) of a network node (300, 350, 730, 830, 1400) configured to transmit downlink control information, DCI, to user equipment,

UEs (710, 720, 810, 820, 1300, 1510) in a cell (740, 840) served by the network node in a wireless network (399, 1530), configure the network node to perform operations corresponding to any of the methods of claims 28-38.

56. A computer program product (1421) comprising computer-executable instructions that, when executed by processing circuitry (1410) of a network node (300, 350, 730, 830, 1400) configured to transmit downlink control information, DCI, to user equipment, UEs (710, 720, 810, 820, 1300, 1510) in a cell (740, 840) served by the network node in a wireless network (399, 1530), configure the network node to perform operations corresponding to any of the methods of claims 28-38.