Sidelink resource pool activation and deactivation for power savings

Apparatus, methods, and computer-readable media for facilitating sidelink resource pool activation and deactivation for sidelink communication are disclosed herein. An example method for wireless communication at a first sidelink device includes identifying a configuration of a bandwidth part (BWP) for sidelink communication. In some examples, the BWP may comprise at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources. The example method also includes receiving an activation indication activating the second subset of frequency resources of the second resource pool. Additionally, the example method includes activating the second subset of frequency resources of the second resource pool based on the activation indication.

BACKGROUND

Technical Field

The present disclosure relates generally to communication systems, and more particularly, to sidelink communication.

Introduction

SUMMARY

In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided for wireless communication of a first sidelink device. An example apparatus identifies a configuration of a bandwidth part (BWP) for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources. The example apparatus also receives an activation indication activating the second subset of frequency resources of the second resource pool. Additionally, the example apparatus activates the second subset of frequency resources of the second resource pool based on the activation indication.

In another aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided for wireless communication of a first sidelink device. An example apparatus identifies a configuration of a bandwidth part (BWP) for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources. The example apparatus also transmits an activation indication to a second sidelink device, the activation indication activating the second subset of frequency resources of the second resource pool. Additionally, the example apparatus transmits a sidelink transmission to the second sidelink device in the second subset of frequency resources of the second resource pool.

In another aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided for wireless communication of a base station. An example apparatus identifies identifying a configuration of a bandwidth part (BWP) for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources. The example apparatus also transmits an activation indication activating the second subset of frequency resources of the second resource pool.

DETAILED DESCRIPTION

The use of a bandwidth part (BWP) that includes a subset of contiguous resource blocks within a frequency range of a carrier may enable a user equipment (UE) to achieve power savings. Sidelink communication that occurs directly between UEs may include unique challenges to avoid interference that are different than communication between a UE and a base station. Sidelink communication may include a single BWP for a sidelink carrier. The use of a single BWP for a sidelink carrier may help to avoid interference among sidelink transmissions. However, a single BWP constrains an ability to provide power savings through communication when there are changes in instantaneous traffic. For example, a receiving sidelink UE may scan all resources/subchannels in a frequency domain corresponding to the BWP to receive a packet, regardless of the amount of traffic the receiving sidelink UE expects. Aspects presented herein provide for the configuration of multiple resource pools at the BWP in a sidelink carrier. Bandwidth adaptation may be performed to achieve power saving over sidelink by activating and/or deactivating one or more resource pools based on, for example, changes in instantaneous traffic needs.

Some examples of sidelink communication may include vehicle-based communication devices that can communicate from vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I) (e.g., from the vehicle-based communication device to road infrastructure nodes such as a Road Side Unit (RSU)), vehicle-to-network (V2N) (e.g., from the vehicle-based communication device to one or more network nodes, such as a base station), vehicle-to-pedestrian (V2P), cellular vehicle-to-everything (C-V2X), and/or a combination thereof and/or with other devices, which can be collectively referred to as vehicle-to-anything (V2X) communications. Sidelink communication may be based on V2X or other D2D communication, such as Proximity Services (ProSe), etc. In addition to UEs, sidelink communication may also be transmitted and received by other transmitting and receiving devices, such as Road Side Unit (RSU)107, etc. Sidelink communication may be exchanged using a PC5 interface, such as described in connection with the example inFIG.2. Although the following description, including the example slot structure ofFIG.2, may provide examples for sidelink communication in connection with 5G NR, the concepts described herein may be applicable to other similar areas, such as LTE, LTE-A, CDMA, GSM, and other wireless technologies.

In some examples, a wireless communication device, such as a UE104or other device communicating based on sidelink, may be configured to manage one or more aspects of wireless communication by facilitating activating and deactivating resources pools in a bandwidth part of a sidelink carrier based on a received indication. As an example, inFIG.1, the UE104may include a sidelink resource pool component198configured to identify a configuration of a bandwidth part (BWP) for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources. The example sidelink resource pool component198may also be configured to receive an activation indication activating the second subset of frequency resources of the second resource pool. Additionally, the example sidelink resource pool component198may be configured to activate the second subset of frequency resources of the second resource pool based on the activation indication.

In some examples, the wireless communication, such as the UE104or other device communicating based on sidelink, may be configured to manage one or more aspects of wireless communication by facilitating activating and deactivating resources pools in a bandwidth part of a sidelink carrier at a receiving sidelink device. As an example, inFIG.1, the UE104may include the sidelink resource pool component198configured to identify a configuration of a BWP for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources. The example sidelink resource pool component198may also be configured to transmit an activation indication to a second sidelink device, the activation indication activating the second subset of frequency resources of the second resource pool. Additionally, the example sidelink resource pool component198may be configured to transmit a sidelink transmission to the second sidelink device in the second subset of frequency resources of the second resource pool.

Still referring toFIG.1, in some examples, a communication device, such as a base station102/180, may be configured to manage one or more aspects of wireless communication by facilitating activating and deactivating resources pools in a bandwidth part of a sidelink carrier at a sidelink device. As an example, inFIG.1, the base station102/180may include a sidelink resource pool configuration component199configured to identify a configuration of a BWP for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources. The example sidelink resource pool configuration component199may also be configured to transmit an activation indication activating the second subset of frequency resources of the second resource pool.

FIG.2includes diagrams200and210illustrating example aspects of slot structures that may be used for sidelink communication (e.g., between UEs104, RSU107, etc.). The slot structure may be within a 5G/NR frame structure in some examples. In other examples, the slot structure may be within an LTE frame structure. Although the following description may be focused on 5G NR, the concepts described herein may be applicable to other similar areas, such as LTE, LTE-A, CDMA, GSM, and other wireless technologies. The example slot structure inFIG.2is merely one example, and other sidelink communication may have a different frame structure and/or different channels for sidelink communication. A frame (10 ms) may be divided into 10 equally sized subframes (1 ms). Each subframe may include one or more time slots. Subframes may also include mini-slots, which may include 7, 4, or 2 symbols. Each slot may include 7 or 14 symbols, depending on the slot configuration. For slot configuration 0, each slot may include 14 symbols, and for slot configuration 1, each slot may include 7 symbols. Diagram200illustrates a single resource block of a single slot transmission, e.g., which may correspond to a 0.5 ms transmission time interval (TTI). A physical sidelink control channel may be configured to occupy multiple physical resource blocks (PRBs), e.g., 10, 12, 15, 20, or 25 PRBs. The PSCCH may be limited to a single sub-channel. A PSCCH duration may be configured to be 2 symbols or 3 symbols, for example. A sub-channel may comprise 10, 15, 20, 25, 50, 75, or 100 PRBs, for example. The resources for a sidelink transmission may be selected from a resource pool including one or more subchannels. As a non-limiting example, the resource pool may include between 1-27 subchannels. A PSCCH size may be established for a resource pool, e.g., as between 10-100% of one subchannel for a duration of 2 symbols or 3 symbols. The diagram210inFIG.2illustrates an example in which the PSCCH occupies about 50% of a subchannel, as one example to illustrate the concept of PSCCH occupying a portion of a subchannel. The physical sidelink shared channel (PSSCH) occupies at least one subchannel. The PSCCH may include a first portion of sidelink control information (SCI), and the PSSCH may include a second portion of SCI in some examples.

A resource grid may be used to represent the frame structure. Each time slot may include a resource block (RB) (also referred to as physical RBs (PRBs)) that extends12consecutive subcarriers. The resource grid is divided into multiple resource elements (REs). The number of bits carried by each RE depends on the modulation scheme. As illustrated inFIG.2, some of the REs may comprise control information in PSCCH and some Res may comprise demodulation RS (DMRS). At least one symbol may be used for feedback.FIG.2illustrates examples with two symbols for a physical sidelink feedback channel (PSFCH) with adjacent gap symbols. A symbol prior to and/or after the feedback may be used for turnaround between reception of data and transmission of the feedback. The gap enables a device to switch from operating as a transmitting device to prepare to operate as a receiving device, e.g., in the following slot. Data may be transmitted in the remaining REs, as illustrated. The data may comprise the data message described herein. The position of any of the data, DMRS, SCI, feedback, gap symbols, and/or LBT symbols may be different than the example illustrated inFIG.2. Multiple slots may be aggregated together in some examples.

FIG.3is a block diagram300of a first wireless communication device310in communication with a second wireless communication device350based on sidelink. In some examples, the wireless communication devices310,350may communicate based on V2X or other D2D communication. The communication may be based on sidelink using a PC5 interface. The wireless communication devices310,350may comprise a UE, an RSU, a base station, etc. Packets may be provided to a controller/processor375that implements layer 3 and layer 2 functionality. Layer 3 includes a radio resource control (RRC) layer, and layer 2 includes a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer.

The controller/processor359can be associated with a memory360that stores program codes and data. The memory360may be referred to as a computer-readable medium. The controller/processor359may provide demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing. The controller/processor359is also responsible for error detection using an acknowledgement (ACK) and/or negative acknowledgement (NACK) protocol to support HARQ operations.

The transmission is processed at the first wireless communication device310in a manner similar to that described in connection with the receiver function atthe second wireless communication device350. Each receiver318RX receives a signal through its respective antenna320. Each receiver318RX recovers information modulated onto an RF carrier and provides the information to an RX processor370.

The controller/processor375can be associated with a memory376that stores program codes and data. The memory376may be referred to as a computer-readable medium. The controller/processor375provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing. The controller/processor375is also responsible for error detection using an acknowledgement (ACK) and/or negative acknowledgement (NACK) protocol to support HARQ operations.

At least one of the TX processor368, the RX processor356, and the controller/processor359may be configured to perform aspects in connection with the sidelink resource pool component198ofFIG.1.

At least one of the TX processor316, the RX processor370, and the controller/processor375may be configured to perform aspects in connection with the sidelink resource pool configuration component199ofFIG.1.

FIG.4illustrates an example400of wireless communication between devices based on sidelink communication. The communication may be based on a slot structure comprising aspects described in connection withFIG.2. For example, a first UE402may transmit a transmission414, e.g., comprising a control channel (e.g., a PSCCH) and/or a corresponding data channel (e.g., a PSSCH), that may be received by a second UE404, a third UE406, and/or a fourth UE408directly from the first UE402, e.g., without being transmitted through a base station. The UEs402,404,406,408may each be capable of operating as a transmitting device in addition to operating as a receiving device. Thus, the third UE406is illustrated as transmitting a transmission416and the fourth UE408is illustrated as transmitting a transmission420. The transmissions414,416,420may be broadcast or multicast to nearby devices. For example, the first UE402may transmit communication intended for receipt by other UEs within a range401of the first UE402. Additionally, or alternatively, an RSU407may receive communication from and/or transmit communication418to the UEs402,404,406,408.

The first UE402may provide sidelink control information (SCI) with information for decoding the corresponding data channel. The SCI may also include information that a receiving device may use to avoid interference. For example, the SCI may indicate time and frequency resources that will be occupied by the data transmission, and may be indicated in a control message from the transmitting device.

In some examples, a base station430may communicate with one or more communication devices within a range432of the base station430. For example, the base station430may communicate with the first UE402, the second UE404, the fourth UE408, and the RSU407. Although the third UE406is not within the range432of the base station430, in some examples, the first UE402may be configured to operate as a relay that helps to connect the third UE406to the base station430by relaying traffic between the third UE406and the base station430. For example, the base station430may transmit a message via a transmission434that is received by the first UE402, and the first UE402may transmit (or forward) the message to the third UE406via sidelink. In another example, the third UE406may transmit a message via sidelink that is received by the first UE402, and the first UE402may transmit (or forward) the message to the base station430via an uplink transmission. In some such examples, the first UE402may be referred to as a “relay” device and the third UE406may be referred to as a “remote” device.

In examples disclosed herein, when a UE transmits a transmission for sidelink communication, the transmitting UE may be referred to as a “sidelink transmitting UE” or a “sidelink transmitting device.” When a UE receives a transmission via sidelink the receiving UE may be referred to as a “sidelink receiving UE” or a “sidelink receiving device.” For example, in the example ofFIG.4, the first UE402(e.g., a sidelink transmitting UE) may transmit the transmission414via sidelink. The second UE404(e.g., a sidelink receiving UE) may receive, via sidelink, a transmission422corresponding to the transmission414.

In cellular link communication between a base station (e.g., the base station102or180) and a UE (e.g., the UE104) over a Uu link, the UE may achieve power savings through the use of a configured BWP that includes a frequency range that is a portion of a carrier bandwidth.FIG.5illustrates an example frequency diagram500showing multiple BWPs (e.g., a first BWP502and a second BWP504) within a carrier bandwidth506. Each BWP includes a set of contiguous physical RBs. The active BWP(s) of the UE may change dynamically over time, e.g., depending on a traffic pattern between the UE and the base station. The use of the BWPs may enable a UE to communicate with the base station over a narrower bandwidth, which may use less power at the UE.

FIG.6illustrates an example600of BWP switching for downlink reception by a UE of a downlink transmission from a base station. The UE may monitor a narrower BWP (e.g., a BWP 1) for a control channel transmission602from the base station. The control channel transmission602does not include a downlink grant for the UE. At a next slot (e.g., at a slot n+1), the UE may receive a downlink grant in a control channel transmission604, the downlink grant indicating BWP 1 (e.g., “BWP ID=1”). Thus, the UE continues to monitor a narrower bandwidth608of BWP 1. The UE may receive a control channel transmission606and/or data610within the frequency resources of the BWP 1.

In another slot (e.g., a slot m+1 ofFIG.6), the UE may receive a downlink grant in a control channel transmission612that indicates a different BWP, e.g., a BWP 2 (e.g., “BWP ID=2”). As illustrated at614, the UE switches to monitor the indicated BWP, as shown at616. The UE receives downlink data618on frequency resources of BWP 2. The UE may switch back to monitoring the narrower bandwidth of BWP 1. For example, if the UE has not received data and a timer expires, the UE may switch, at620, back to monitoring BWP 1.

FIG.7illustrates examples of BWP switching for downlink and uplink transmissions from a UE. In a downlink time division duplex (TDD) example700, a UE receives downlink control information (DCI)702in a first BWP with a downlink grant for the UE to receive PDSCH704in a second BWP. The UE performs a BWP switch from the first BWP to the second BWP in order to receive the PDSCH704. The UE then transmits feedback706(e.g., ACK/NACK) in the second BWP. An RF switching latency for the UE to switch from the first BWP to the second BWP may be provided for with a delay parameter (e.g., a k0 parameter) between the DCI702and the PDSCH704reception. A K1 parameter may provide a delay between the PDSCH704reception and the feedback706.

In a downlink frequency division duplex (FDD) example750, a UE receives DCI712in a first BWP of a first carrier with a downlink grant for the UE to receive PDSCH714in a second BWP of the first carrier. The UE performs a BWP switch from the first BWP to the second BWP for the first carrier in order to receive the PDSCH714. The UE then transmits feedback716in a different carrier. The RF switching latency for the UE to switch from the first BWP to the second BWP may be provided for with a delay parameter (e.g., the k0 parameter) between the DCI712and the PDSCH714reception, similar to the TDD example700. In the examples700and750, the PDSCH may be in the new BWP, e.g., involving a BWP switch from the BWP in which the DCI with the downlink grant is received. In the TDD example700, the UE may apply a new DL/UL BWP pair, e.g., transmitting the feedback706(ACK) in a new uplink BWP. In the FDD example750, the UE may receive the PDSCH714in the new BWP, and may transmit feedback716in a prior uplink BWP.

In an uplink TDD example725, the UE receives DCI708, in a first BWP, with an uplink grant for the UE to transmit PUSCH710in a second BWP. The UE performs a BWP switch from the first BWP to the second BWP in order to transmit the PUSCH710. The RF switching latency for the UE to switch from the first BWP to the second BWP may be provided for with a delay parameter (e.g., a k2 parameter) between the DCI708and the PUSCH710transmission.

In an uplink FDD example775, the UE may be configured for a first BWP for a first carrier. The UE receives DCI718, on a second carrier, with an uplink grant for the UE to transmit PUSCH720in a second BWP of the first carrier. The UE performs a BWP switch from the first BWP to the second BWP for the first carrier in order to transmit the PUSCH720. The RF switching latency for the UE to switch from the first BWP to the second BWP on the first carrier may be provided for with a delay parameter (e.g., the k2 parameter) between the DCI718and the PUSCH720transmission. In the examples725and775, the PUSCH may be transmitted in the new BWP, e.g., involving a BWP switch from the BWP in which the DCI with the uplink grant is received. As illustrated in the FDD examples750and775, the UL and DL BWP may be switched independently.

The size of the DCI in different BWPs may be different due to the different bandwidth sizes of the BWPs. In some examples, a DCI in one BWP may indicate a grant in a different BWP. For example, the DCI may provide for different bandwidths for the control channel with the grant and the data based on the grant.

In some examples, a single BWP may be configured within a sidelink carrier.FIG.8illustrates an example hierarchy for a configuration for sidelink communication800including a sidelink BWP configuration808. As illustrated inFIG.8, a sidelink configuration802may include a sidelink frequency configuration804, among other aspects. A sidelink UE may receive the sidelink configuration802(e.g., from a base station or another sidelink). In some examples, the sidelink UE may be configured with the sidelink configuration802. The sidelink frequency configuration804may have aspects that correspond to a carrier configuration in Uu-based communication (e.g., cellular communication). The sidelink frequency configuration804may include a reference point, e.g., point A806, a physical sidelink broadcast channel (PSBCH) configuration810, and/or a subcarrier spacing (SCS) specific carrier list812. The SCS specific carrier list812may include SCS specific configurations818for bandwidth, location, etc. The sidelink frequency configuration804may include the sidelink BWP configuration808. The sidelink BWP configuration808may include a generic BWP configuration814. The generic BWP configuration814may include one or more parameters820such as a bandwidth and frequency location for the generic BWP, an SCS and cyclic prefix (CP) for the generic BWP, and/or one or more time domain resources for the generic BWP. The sidelink BWP configuration808may include one or more resource pool configurations816. Each resource pool configuration816may include one or more resource pools822for sidelink communication.

A BWP may be wider in the frequency domain than a resource pool, and one BWP may include multiple receiving and transmitting resource pools. For example,FIG.8illustrates two transmission resource pools and at least one reception resource pool. As an example, different transmission pools may be configured for different modes of resource allocation. For example, at least one transmission resource pool may be configured for centralized resource allocation (e.g., mode 1 resource allocation in which a base station or other central entity allocates resources to various UEs for sidelink communication). At least one transmission resource pool may be configured for decentralized resource allocation (e.g., mode 2 resource allocation or sensing-based resource allocation in which each UE determines its own transmission resources from the resource pool). The resource pools822may further include one or more reception resource pools. Each resource pool may include a resource pool configuration824that includes a configuration of one or more of a PSSCH, PSCCH, or PSFCH. Each resource pool configuration824may include a number of subchannels, subchannel size, starting RB, a code block rate (CBR), modulation and coding scheme (MCS), sensing configuration (e.g., for mode 2 resource allocation), and/or power control configuration, among others. In some examples, each resource pool configuration may include a maximum number of reception pools and/or transmission pools. For example, a sidelink BWP may include a maximum of sixteen reception pools and a maximum of eight transmission pools. It may be appreciated that in some examples, one or more of the resource pools822may comprise a same or overlapping resource allocation.

Aspects presented herein provide for a single BWP of a sidelink carrier to be configured with a primary resource pool and one or more secondary resource pools. The primary resource pool (sometimes referred to as a “default resource pool”) may comprise a subset of frequency resources that are activated and configured to provide a minimum bandwidth that the sidelink UE manages and/or monitors. The one or more secondary resource pools may comprise respective subsets of frequency resources that are capable of being activated and deactivated. The activation and deactivation of the resource pools may improve power savings at a sidelink device while also providing different frequency resources for different traffic needs. For example, to accommodate periods with high traffic, one or more secondary resource pools may be activated, thereby increasing the resources available for sidelink communication. To accommodate periods with low or no traffic, one or more secondary resource pools may be deactivated, thereby reducing the resources the sidelink device monitors. Thus, aspects disclosed herein provide techniques for bandwidth adaptation using the activation and deactivation of one or more resource pools within a single BWP of a sidelink carrier.

FIG.9illustrates a configuration900of a single BWP902(e.g., a BWP 1) in a carrier904for sidelink communication. In some examples, a sidelink UE (e.g., the UE104and/or the UEs402,404,406,408) may receive the configuration900from a wireless communication device, such as a base station or a sidelink transmitting UE. In some examples, the sidelink UE may be configured with the configuration900. The example BWP902includes three resource pools (e.g., a resource pool 1, a resource pool 2, and a resource pool 3). Each of the resource pools may be associated with a respective subset of frequency resources. For example, in the configuration900, the resource pool 3 comprises a subset of frequency resources910.

To maintain a minimum bandwidth to enable a sidelink UE to manage and/or monitor sidelink communication, the configuration900configures (e.g., defines) a primary resource pool906of the BWP902(e.g., the resource pool 1). The primary resource pool906provides the minimum bandwidth (e.g., subset of frequency resources) to enable the sidelink UE to receive and/or transmit sidelink communication. In some examples, the primary resource pool906may be unable to be deactivated. That is, the sidelink UE may monitor at least the resources associated with the primary resource pool906when monitoring for sidelink communication, regardless of whether one or more additional resource pools are activated or deactivated.

To facilitate BWP adaptation, the configuration900of the BWP902also defines one or more secondary resource pools that may be activated and deactivated. For example, the configuration900configures (e.g., defines) a first secondary resource pool908a(e.g., the resource pool 2) and a second secondary resource pool908b(e.g., the resource pool 3). When the configuration900is initiated, the secondary resource pools908a,908bmay be deactivated. While managing sidelink communication, the secondary resource pools908a,908bmay be activated or deactivated based on instantaneous traffic needs. For example, when traffic increases, one or both of the secondary resource pools908a,908bmay be activated. When traffic decreases, one or both of the active secondary resource pools908a,908bmay be deactivated. In this manner, the sidelink UE may adapt the bandwidth being managed and/or monitored and, thus, conserve power by reducing the resources/subchannels that the sidelink UE monitors during periods of low traffic.

The secondary resource pools908a,908bmay be activated through signaling from an activating device. For example, a sidelink UE may receive an activation indication activating the first secondary resource pool908avia layer 1 signaling, such as control information or a wake-up signal. As shown inFIG.9, an activation indication activates the first secondary resource pool908a. In some examples, the sidelink UE may receive an activation indication activating the first secondary resource pool908avia layer 2 signaling, such as a medium access control (MAC) control element (MAC-CE) or RRC signaling. The sidelink UE may receive the activation indication activating the first secondary resource pool908avia a resource of the primary resource pool906. That is, since the sidelink receiving UE monitors at least the resources associated with the primary resource pool906, the sidelink receiving UE is capable of receiving an activation indication regardless of the activated/deactivated status of the secondary resource pools908a,908b. However, it may be appreciated that when at least one of the secondary resource pools908a,908bis/are activated, the sidelink receiving UE may receive the activation indication via resources associated with the primary resource pool906and/or resources associated with the activated one(s) of the secondary resource pools908a,908b.

In a first aspect, the activating device may comprise a base station, such as the base station430ofFIG.4. For example, the base station may receive information regarding upcoming traffic and signal to a sidelink device (e.g., a sidelink transmitting device and/or a sidelink receiving device) to activate one or more secondary resource pools. In some examples, the base station may signal to a sidelink receiving device to activate to one or both of the secondary resource pools908a,908bby transmitting a downlink activation indication to the sidelink receiving UE. For example, and referring to the example ofFIG.4, the base station430may signal to the second UE404to activate the first secondary resource pool908aby transmitting a downlink activation indication (e.g., the transmission434). In such examples, the layer 1 signaling comprising the downlink activation indication from the base station may include DCI or a downlink wake-up signal. Layer 2 signaling comprising the downlink activation indication from the base station may include a downlink MAC-CE or downlink RRC signaling.

In another aspect, the activating device may comprise a sidelink transmitting UE, such as the first UE402ofFIG.4. For example, and referring to the example ofFIG.4, the first UE402may transmit a sidelink activation indication (e.g., the transmission414) to the second UE404ofFIG.4to activate the first secondary resource pool908a. In such examples, the layer 1 signaling comprising the sidelink activation indication from the sidelink transmitting UE may include SCI or a sidelink wake-up signal. Layer 2 signaling comprising the sidelink activation indication from the sidelink transmitting UE may include a sidelink MAC-CE or sidelink RRC signaling.

In some examples, the sidelink transmitting UE may determine to transmit the sidelink activation indication to the sidelink receiving UE based on information regarding upcoming sidelink traffic. In some examples, the sidelink transmitting UE may transmit the sidelink activation indication to the sidelink receiving UE based on a downlink activation indication received from a base station. For example, and referring to the example ofFIG.4, the base station430may receive information regarding upcoming traffic and signal to the first UE402(e.g., via the transmission434) to activate the first secondary resource pool908a. The first UE402may activate the first secondary resource pool908abased on the signaling received from the base station430. The first UE402may also transmit the sidelink activation indication to the second UE404(e.g., via the transmission414) to cause the second UE404to activate the first secondary resource pool908abased on the signaling received by the first UE402from the base station430. The first UE402may transmit the sidelink activation indication to the second UE404via resources associated with the primary resource pool906. In some such examples, the first UE402(e.g., the sidelink transmitting UE or “relay” device) may help connect the second UE404(e.g., the sidelink receiving UE or “remote” device) to the base station430by relaying traffic between the second UE404and the base station430.

In some examples, the signaling received by the sidelink transmitting UE to activate the secondary resource pool(s) from the base station may comprise DCI. In some such examples, the DCI may schedule a sidelink grant in the secondary resource pool. For example, the base station may transmit a DCI format 3_x (e.g., DCI format 3_0 or DCI format 3_1) to indicate to the sidelink transmitting UE to activate the first secondary resource pool908afor sidelink communication. The DCI format 3_x may also schedule a sidelink grant indicating a set of frequency resources of the first secondary resource pool908afor the sidelink transmitting UE to use for transmitting sidelink communications to the sidelink receiving UE.

After the sidelink UEs activate one or more secondary resource pools (e.g., based on the downlink activation indication from the base station or the sidelink activation indication from the sidelink transmitting UE), the sidelink receiving UE may receive sidelink communication from the sidelink transmitting UE. When managing sidelink communication, the sidelink receiving UE may monitor the subset of frequency resources associated with the resource pool(s) that are activated. For example, in the example ofFIG.9, when the configuration900is initiated, the sidelink receiving UE may monitor for sidelink communication in the subset of frequency resources of the primary resource pool906, since the primary resource pool906is activated and the secondary resource pools908a,908bare deactivated. After the sidelink receiving UE activates the one or more secondary resource pools (e.g., the first secondary resource pool908ain the example ofFIG.9), the sidelink receiving UE may monitor for sidelink communication in the subset of frequency resources of the BWP902of the carrier904associated with the primary resource pool906and the first secondary resource pool908a.

The sidelink UEs may continue sidelink communication using the active secondary resource pool(s) until a deactivation event is detected. In some examples, the deactivation event may include a deactivation indication. For example, the sidelink receiving UE may receive the deactivation indication based on a decrease in sidelink traffic. In a similar manner as the activation indication, the sidelink UEs may receive a deactivation indication from a sidelink transmitting UE or the base station. For example, a sidelink UE may receive a downlink deactivation indication from the base station (e.g., DCI, a downlink wake-up signal, a downlink MAC-CE, and/or downlink RRC signaling) or from the sidelink transmitting UE (e.g., SCI, a sidelink wake-up signal, a sidelink MAC-CE, and/or sidelink RRC signaling).

In some examples, the deactivation event may be based on a timer. For example, an active secondary resource pool may be deactivated if a threshold amount of traffic is not received or transmitted on the active secondary resource pool for a period (e.g., a deactivation period). In some examples, the threshold amount of traffic may correspond to zero traffic. For example, if no traffic is transmitted or received on the active secondary resource pool for the period, then the active secondary resource pool may be deactivated. In some examples, the threshold amount of traffic may be greater than zero traffic. For example, if the amount of traffic received or transmitted for the period is greater than zero traffic and less than the threshold amount of traffic, then the active secondary resource pool may be deactivated.

In some examples, the sidelink UE may initiate a timer (e.g., a deactivation timer) when a secondary resource pool is activated. The sidelink UE may reset the deactivation timer each time traffic (e.g., the threshold amount of traffic) is received or transmit on the active resource pool. In some such examples, when the deactivation timer expires (e.g., the threshold amount of traffic is not received or transmitted while the deactivation timer is active), the sidelink UE deactivates the active resource pool.

In some examples, an activation indication may activate multiple secondary resource pools. For example, an activation indication may activate the first secondary resource pool908aand the second secondary resource pool908b. In some examples, a deactivation indication may deactivate multiple secondary resource pools. For example, a deactivation indication may deactivate the first secondary resource pool908aand the second secondary resource pool908b(e.g., when the secondary resource pools908a,908bare active). It may be beneficial to activate and/or deactivate one or more resource pools using a same signaling to reduce signaling overhead.

In some examples, an activation indication or a deactivation indication may activate one or more resource pools and deactivate one or more resource pools. For example, after the first secondary resource pool908ais activated, an activation indication (or a deactivation indication) may activate the second secondary resource pool908band deactivate the first secondary resource pool908a. For example, the first secondary resource pool908amay experience increased interference and, thus, it may be beneficial to switch to activating the second secondary resource pool908b. In some aspects, the respective secondary resource pools908a,908bmay comprise different amounts of resources. For example, the first secondary resource pool908amay comprise fewer resources than the second secondary resource pool908b. In some such examples, when an increase in traffic is upcoming, the first secondary resource pool908amay be activated, but when an additional increase in traffic is detected, it may be beneficial to switch to the second secondary resource pool908bfor the sidelink communication (e.g., by activating the second secondary resource pool908band deactivating the first secondary resource pool908a).

FIG.10illustrates an example timing1000of resource pool activation and deactivation of a secondary resource pool1004via sidelink signaling, as presented herein. The signaling (e.g., layer 1 signaling, such as SCI or a sidelink wake-up signal, or layer 2 signaling, such as a sidelink MAC-CE or sidelink RRC signaling) may comprise an activation indication and/or a deactivation indication.

As shown inFIG.10, the activating of the secondary resource pool1004occurs after SCI1010and ACK1014. For example, at time T0, a primary resource pool1002is activate and the secondary resource pool1004is deactivated. Aspects of the primary resource pool1002may be implemented by the primary resource pool906ofFIG.9. Aspects of the secondary resource pool1004may be implemented by the first secondary resource pool908aofFIG.9. At time T1, a sidelink UE receives or transmits the SCI1010activating the secondary resource pool1004. At time T3, the secondary resource pool1004is activated. At time T4, the sidelink UE receives or transmits SCI1020deactivating the secondary resource pool1004. At time T6, the secondary resource pool1004is deactivated.

In the example ofFIG.10, a sidelink UE may monitor for and/or manage sidelink communication using the frequency resources associated with active resource pools. For example, between time T0 and time T3 (e.g., a first interval1030), the sidelink transmitting UE may transmit sidelink communication to the sidelink receiving UE using the frequency resources associated with the primary resource pool1002. The receiving UE may monitor for sidelink communication from the sidelink transmitting UE using the frequency resources associated with the primary resource pool1002for the first interval1030. Between the time T3 and time T6 (e.g., a second interval1032), the sidelink transmitting UE may transmit sidelink communication to the sidelink receiving UE using the frequency resources associated with the primary resource pool1002and/or the secondary resource pool1004. The sidelink receiving UE may monitor for sidelink communication from the sidelink transmitting UE using the frequency resources associated with the primary resource pool1002and/or the secondary resource pool1004for the second interval1032. After the time T6 (e.g., a third interval1034), the sidelink transmitting UE may transmit sidelink communication to the sidelink receiving UE using the frequency resources associated with the primary resource pool1002. The sidelink receiving UE may monitor for sidelink communication from the sidelink transmitting UE using the frequency resources associated with the primary resource pool1002for the third interval1034. Thus, the sidelink receiving UE may conserve power by monitoring the frequency resources associated with the primary resource pool1002and not the frequency resources associated with the secondary resource pool1004for the first interval1030and the third interval1034. The first interval1030and the third interval1034may be associated with little or no traffic (e.g., less than a threshold amount of traffic) and the second interval1032may be associated with high traffic (e.g., greater than a threshold amount of traffic).

Activation indications and deactivation indications may be transmitted and received in active resource pools. For example, for the first interval1030, the SCI1010comprising an activation indication to activate the secondary resource pool1004is transmitted and received on resources associated with the primary resource pool1002. For the second interval1032, an activation indication (e.g., activating a different secondary resource pool) or a deactivation indication (e.g., deactivating the secondary resource pool1004) may be transmitted and received on resources associated with the primary resource pool1002or the secondary resource pool1004. For the third interval1034, an activation indication to activate the secondary resource pool1004may be transmitted and received on resources associated with the primary resource pool1002.

In some examples, the activating and/or deactivating of a secondary resource pool may occur after feedback. For example, a sidelink transmitting UE may activate the secondary resource pool1004by transmitting the SCI1010to a sidelink receiving UE (e.g., at the time T1). As shown inFIG.10, the activating of the secondary resource pool1004does not occur until after the sidelink receiving UE transmits a feedback message (e.g., the ACK1014) at the time T2. The sidelink receiving UE may transmit the ACK1014using a sidelink feedback channel (e.g., PSFCH). In a similar manner, the sidelink transmitting UE may deactivate the secondary resource pool1004by transmitting the SCI1020to the sidelink receiving UE (e.g., at the time T4). As shown inFIG.10, the deactivating of the secondary resource pool1004does not occur until after the sidelink receiving UE transmits a feedback message (e.g., ACK1024) at time T5. Thus, it may be appreciated that there may be a delay between the time at which an activation indication and/or deactivation indication is transmitted and the time at which the corresponding resource pool is activated or deactivated. In some examples, the sidelink receiving UE may transmit the feedback message using a sidelink MAC-CE. For example, the sidelink MAC-CE may be used to acknowledge the activation of a resource pool (e.g., the ACK1014acknowledging the activating of the secondary resource pool1004) and/or acknowledge the deactivation of a resource pool (e.g., the ACK1024acknowledging the deactivating of the secondary resource pool1004).

In some examples, the feedback message (e.g., the ACK1014,1024) may be based on the SCI. For example, the SCI activating and/or deactivating the secondary resource pool may or may not schedule a data transmission (e.g., PSSCH1012). If the SCI activating and/or deactivating the secondary resource pool foregoes scheduling a data transmission (e.g., the SCI1020), the feedback message (e.g., the ACK1024) may acknowledge whether the sidelink receiving UE received the SCI. If the SCI activating and/or deactivating the secondary resource pool schedules a data transmission (e.g., the SCI1010), the feedback message (e.g., the ACK1014) may be based on the decoding of the data transmission and acknowledge receipt of the SCI. When the SCI activating and/or deactivating the secondary resource pool schedules a data transmission, the sidelink receiving UE may activate and/or deactivate the secondary resource pool regardless of whether the sidelink receiving UE successfully decodes the data transmission scheduled by the SCI.

In some examples, the sidelink UEs may perform bi-directional sidelink communications. In such examples, each sidelink UE may signal to the other sidelink UE whether to activate and/or deactivate a respective secondary resource pool. For example, a first sidelink UE may transmit an activation indication to a second sidelink UE to activate a secondary resource pool. The second sidelink UE may then proceed to monitor the primary resource pool and the secondary resource pool for sidelink communications from the first sidelink UE. The second sidelink UE may also determine to transmit sidelink communications to the first sidelink UE and transmit an activation indication to the first sidelink UE to activate the secondary resource pool. In such examples, the first sidelink UE may start monitoring the primary resource pool and the secondary resource pool for sidelink communication from the second sidelink UE. In a similar manner, each of the sidelink UEs may transmit a deactivation indication to the other sidelink UE to cause the other sidelink UE to deactivate the secondary resource pool.

It may be appreciated that in some examples, each of the sidelink UEs may activate a different resource pool for the bi-directional sidelink communication. For example, the first sidelink UE may transmit an activation indication activating a first secondary resource pool and the second sidelink UE may transmit an activation indication activating a second secondary resource pool. In some such examples, the first sidelink UE may transmit a sidelink communication to the second sidelink UE using the resources associated with the primary resource pool and the first secondary resource pool, and the first sidelink UE may monitor for sidelink communication from the second sidelink UE on the resources associated with the primary resource pool and the second secondary resource pool. In a similar manner, the second sidelink UE may transmit a sidelink communication to the first sidelink UE using the resources associated with the primary resource pool and the second secondary resource pool, and the second sidelink UE may monitor for sidelink communication from the first sidelink UE on the resources associated with the primary resource pool and the first secondary resource pool.

In some examples, an activation indication activating a secondary resource pool transmit by a first sidelink UE enables bi-directional sidelink communication by both of the UEs using the resources associated with the primary resource pool and the secondary resource pool. For example, when the first sidelink UE transmits an activation indication to a second sidelink UE, the first sidelink UE may also start monitoring for sidelink communication from the second sidelink UE on the resources of the primary resource pool and the secondary resource pool. In some examples, either of the sidelink UEs may deactivate the secondary resource pool for bi-directional sidelink communication by transmitting a deactivation indication to the other sidelink UE. In some examples, each of the sidelink UEs may transmit a deactivation indication to the other sidelink UE to cause the other sidelink UE to deactivate the secondary resource pool. For example, the first sidelink UE may transmit a deactivation indication to the second sidelink UE to cause the second sidelink UE to deactivate the secondary resource pool and to cause the second sidelink UE to stop monitoring the resources associated with the secondary resource pool. In some such examples, the first sidelink UE may continue monitoring the resources associated with the secondary resource pool for sidelink communication from the second sidelink UE (e.g., until the first sidelink UE receives a deactivation indication for the secondary resource pool from the second sidelink UE).

FIG.11illustrates an example communication flow1100between abase station1102, a sidelink receiving UE1104, and a sidelink transmitting UE1106, as presented herein. In the illustrated example, the communication flow1100facilitates activating and deactivating resource pools of a single BWP of a sidelink carrier. Aspects of the base station1102may be implemented by the base station102/180ofFIG.1, the first wireless communication device310ofFIG.3, and/or the base station430ofFIG.4. Aspects of the sidelink receiving UE1104may be implemented by the UE104ofFIG.1, the wireless communication devices310,350ofFIG.3, and/or the first UE402ofFIG.4. Aspects of the sidelink transmitting UE1106may be implemented by the UE104ofFIG.1, the wireless communication devices310,350ofFIG.3, and/or the second UE404ofFIG.4. Although not shown in the illustrated example ofFIG.11, it may be appreciated that in additional or alternative examples, the base station1102may be in communication with one or more other base stations or UEs, and/or the sidelink UEs1104,1106may be in communication with one or more other base stations or UEs.

At1110, the sidelink receiving UE1104identifies a configuration of a BWP for sidelink communication. In the illustrated example, the sidelink communication may be between the sidelink receiving UE1104and the sidelink transmitting UE1106. For example, the sidelink transmitting UE1106may transmit a sidelink communication that is received by the sidelink receiving UE1104. Aspects of the configuration of the BWP may be implemented by the configuration900ofFIG.9. For example, the configuration of the BWP may include the primary resource pool906and one or more secondary resource pools (e.g., the secondary resource pools908a,908b). The primary resource pool906may comprise activated frequency resources corresponding to a minimum bandwidth to facilitate sidelink management and/or monitoring. The secondary resource pools908a,908bmay comprise frequency resources that are capable of being activated and deactivated. A secondary resource pool may be activated to increase bandwidth (e.g., to accommodate periods of increased sidelink traffic). An active secondary resource pool may be deactivated when sidelink traffic decreases. Deactivating a secondary resource pool reduces the bandwidth that the sidelink UE monitors for sidelink communication, thereby enabling power savings.

In some examples, the sidelink receiving UE1104may identify the configuration based on information provided by the base station1102and/or the sidelink transmitting UE1102. In some examples, the sidelink receiving UE1104may be configured with the configuration (e.g., pre-configured).

As described above, a secondary resource pool may be activated to increase resources available for sidelink communication. A secondary resource pool may be activated based on an indication. In one aspect, the sidelink receiving UE1104may receive an indication from the base station1102. For example, the base station1102may receive information indicating an increase in sidelink communication and, thus, may facilitate activating a secondary resource pool for sidelink communication. The base station1102may transmit a downlink activation indication1112that is received by the sidelink receiving UE1104. The base station1102may transmit the downlink activation indication1112on a frequency resource of a downlink channel, such as a downlink control channel (e.g., a PDCCH) and/or a downlink data channel (e.g., a PDSCH). In some examples, the base station1102may transmit the downlink activation indication1112on a resource of the primary resource pool. The downlink activation indication1112may comprise layer 1 signaling and/or layer 2 signaling. For example, the downlink activation indication1112may comprise DCI (e.g., DCI format 3_x), a downlink wake-up signal, a downlink MAC-CE, and/or downlink RRC signaling.

In a second aspect, the sidelink receiving UE1104may receive an indication from the sidelink transmitting UE1106. For example, the sidelink transmitting UE1106may determine an increase in sidelink communication and, thus, may facilitate activating a secondary resource pool for sidelink communication. The sidelink transmitting UE1106may transmit a sidelink activation indication1114that is received by the sidelink receiving UE1104. The sidelink transmitting UE1106may transmit the sidelink activation indication1114on a resource of an active resource pool. For example, and referring to the example ofFIG.10, for the first interval1030and/or the third interval1034, the sidelink transmitting UE1106may transmit the sidelink activation indication1114on a resource of the primary resource pool1002. For the second interval1032, the sidelink transmitting UE1106may transmit the sidelink activation indication1114on a resource of the primary resource pool1002and/or a resource of the secondary resource pool1004.

In some examples, the sidelink activation indication1114may comprise SCI that schedules the sidelink receiving UE1104to transmit a feedback message1116(e.g., an ACK or NACK) to the sidelink transmitting UE1106. Aspects of the feedback message1116may be implemented by the ACK1014,1024ofFIG.10. For example, the feedback message1116may acknowledge receipt of the sidelink activation indication1114when the corresponding SCI foregoes scheduling a data transmission (e.g., the SCI1020ofFIG.10). When the SCI schedules a data transmission (e.g., the SCI1010scheduling the PSSCH1012), the feedback message1116may acknowledge receipt of the sidelink activation indication1114and/or whether the sidelink receiving UE1104successfully received the data transmission (e.g., the PSSCH1012). The sidelink receiving UE1104may transmit the feedback message1116to the sidelink transmitting UE1106using a sidelink feedback channel (e.g., a PSFCH) and/or a sidelink MAC-CE acknowledging the activation (or deactivation) of the secondary resource pool.

In another aspect, aspects of the first aspect and the second aspect may be implemented. For example, the base station1102may transmit an activation indication1118that is received by the sidelink transmitting UE1106. The base station1102may transmit the activation indication1118to the sidelink transmitting UE1106based on information indicating an increase in sidelink communication. Similar to the downlink activation indication1112, the activation indication1118may comprise layer 1/layer 2 signaling, such as DCI, a downlink wake-up signal, a downlink MAC-CE, and/or downlink RRC signaling. In some such examples, the sidelink transmitting UE1106may transmit the sidelink activation indication1114to the sidelink receiving UE1104based on the activation indication1118.

In some examples, the activation indication1118may comprise DCI (e.g., DCI format 3_x). The base station1102may use DCI format 3_x (e.g., 3_0 or 3_1) to indicate the activation of the secondary resource pool (e.g., for the sidelink transmitting UE1106) and may schedule a SL grant indicating a set of frequency resources in the secondary resource pool for the sidelink transmitting UE1106to transmit one or more sidelink packets to the sidelink receiving UE1104.

At1120, the sidelink receiving UE1104activates the secondary resource pool based on an activation indication (e.g., the downlink activation indication1112or the sidelink activation indication1114). Aspects of activating the secondary resource pool may be implemented for the second interval1032ofFIG.10. Activating the secondary resource pool increases the resources available for receiving sidelink communication (e.g., sidelink packets) at the sidelink receiving UE1104.

For example, the sidelink transmitting UE1106may transmit a sidelink packet1122that is received by the sidelink receiving UE1104. The sidelink transmitting UE1106may transmit the sidelink packet1122on a resource of an active resource pool. For example, for the second interval1032, the sidelink transmitting UE1106may transmit sidelink communications to the sidelink receiving UE1104on resources of the primary resource pool1002and/or resources of the secondary resource pool1004. The sidelink packet1122may comprise one or more sidelink packets including control information and/or data. Although shown as a single transmission in the example ofFIG.11, it may be appreciated that the sidelink packet1122may comprise one or more transmissions.

In some examples, the sidelink receiving UE1104activates the secondary resource pool (e.g., at1120) based on the feedback message1116. For example, when the sidelink activation indication1114comprises SCI, the SCI may or may not schedule a data transmission. When the SCI does not schedule a data transmission (e.g., the SCI1020ofFIG.10), the feedback message1116may comprise an ACK when the sidelink receiving UE1104successfully decodes the SCI. The feedback message1116may comprise a NACK when the sidelink receiving UE1104is unable to decode the SCI. In such examples, the sidelink receiving UE1104may activate the secondary resource pool (e.g., at1120) when the feedback message1116comprises an ACK and may forego activating the secondary resource pool when the feedback message1116comprises a NACK.

When the SCI schedules a data transmission (e.g., the SCI1010ofFIG.10), the feedback message1116may comprise an ACK when the sidelink receiving UE1104successfully decodes the data transmission (e.g., the PSSCH1012ofFIG.10). The feedback message1116may comprise a NACK when the sidelink receiving UE1104is unable to decode the SCI. In such examples, the feedback message1116may indicate that the sidelink receiving UE1104received the sidelink activation indication1114(e.g., the SCI1010), regardless of whether the sidelink receiving UE1104successfully decoded the data transmission. Thus, the sidelink receiving UE1104may activate the secondary resource pool (e.g., at1120) regardless of whether the feedback message1116comprises an ACK or a NACK.

It may be appreciated that when the feedback message1116indicates that the sidelink receiving UE1104did not receive the sidelink activation indication1114or did not successfully decode the SCI, the sidelink transmitting UE1106may operate as if the secondary resource pool remains deactivated. For example, the sidelink transmitting UE1106may transmit the sidelink packet1122to the sidelink receiving UE1104on the resources of the primary resource pool and not on the resources of the secondary resource pool.

At1130, the sidelink receiving UE1104deactivates the secondary resource pool. Deactivating the secondary resource pool may provide power savings by reducing the bandwidth that the sidelink receiving UE1104monitors for sidelink communication. That is, the sidelink receiving UE1104monitors for sidelink communications on the resources associated with active resource pools. Thus, when a resource pools is deactivated (e.g., at1130), the sidelink receiving UE1104stops monitoring the resources associated with the deactivated resource pool for sidelink communication.

The sidelink receiving UE1104may deactivate the secondary resource pool based on an occurrence of a deactivating event. For example, at1132, the sidelink receiving UE1104may detect an occurrence of a deactivating event. In some examples, the occurrence of a deactivating event may include receiving a deactivation indication. In a first aspect, the sidelink receiving UE1104may receive a deactivation indication from the base station1102. For example, the base station1102may receive information indicating a decrease in sidelink communication and, thus, may facilitate deactivating an active secondary resource pool for sidelink communication. The base station1102may transmit a downlink deactivation indication1134that is received by the sidelink receiving UE1104. The base station1102may transmit the downlink deactivation indication1134on a frequency resource of a downlink channel, such as a downlink control channel (e.g., a PDCCH) and/or a downlink data channel (e.g., a PDSCH). In some examples, the base station1102may transmit the downlink deactivation indication1134on a resource of the primary resource pool. The downlink deactivation indication1134may comprise layer 1 signaling and/or layer 2 signaling. For example, the downlink activation indication1112may comprise DCI (e.g., DCI format 3_x), a downlink wake-up signal, a downlink MAC-CE, and/or downlink RRC signaling.

In a second aspect, the sidelink receiving UE1104may receive the deactivation indication from the sidelink transmitting UE1106. For example, the sidelink transmitting UE1106may determine a decrease in sidelink communication and, thus, may facilitate deactivating an active secondary resource pool for sidelink communication. The sidelink transmitting UE1106may transmit a sidelink deactivation indication1136that is received by the sidelink receiving UE1104. The sidelink transmitting UE1106may transmit the sidelink deactivation indication1136on a resource of an active resource pool. For example, and referring to the example ofFIG.10, for the first interval1030and/or the third interval1034, the sidelink transmitting UE1106may transmit the sidelink deactivation indication1136on a resource of the primary resource pool1002. For the second interval1032, the sidelink transmitting UE1106may transmit the sidelink deactivation indication1136on a resource of the primary resource pool1002and/or a resource of the secondary resource pool1004. The sidelink deactivation indication1136may comprise layer 1 signaling and/or layer 2 signaling. For example, the sidelink deactivation indication1136may comprise SCI, a sidelink wake-up signal, a sidelink MAC-CE, and/or sidelink RRC signaling.

In some examples, the sidelink transmitting UE1106may transmit the sidelink deactivation indication1136to the sidelink receiving UE1104based on a deactivation indication received by the base station1102. For example, the base station1102may transmit a deactivation indication1138that is received by the sidelink transmitting UE1106. The deactivation indication1138may indicate a decrease in sidelink communication and the sidelink transmitting UE1106may transmit the sidelink deactivation indication1136to the sidelink receiving UE1104based on the deactivation indication1138.

In some examples, the deactivation event may be based on a timer. For example, after the sidelink receiving UE1104activates the secondary resource pool (e.g., at1120), the sidelink receiving UE1104may initiate a timer (e.g., at1140). The timer may correspond to a period (e.g., a deactivation period) for which the sidelink receiving UE1104monitors for sidelink communication. When the sidelink receiving UE1104receives sidelink communication that satisfies a threshold amount of traffic, the sidelink receiving UE1104may reset the timer. For example, at1142, the sidelink receiving UE1104may reset the timer based on receipt of the sidelink packet1122. It may be appreciated that the threshold amount of traffic may correspond to receiving any traffic or an amount of traffic greater than zero.

At1144, the sidelink receiving UE1104detects the occurrence of the deactivating event (e.g., at1132) when the timer expires. For example, the sidelink receiving UE1104may not receive the threshold amount of traffic while the timer is active (e.g., for the duration of the deactivation period).

It may be appreciated that when the sidelink receiving UE1104activates the secondary resource pool (e.g., at1120), the sidelink receiving UE1104starts monitoring for sidelink communication on the resources associated with the secondary resource pool. However, the sidelink transmitting UE1106may not monitor for sidelink communication on the resources associated with the secondary resource pool. Thus, to facilitate bi-directional sidelink communication on the resources of the secondary resource pool, the sidelink receiving UE1104may perform the procedure for activating the secondary resource pool at the sidelink transmitting UE1106. For example, the sidelink receiving UE1104may transmit an activation indication to the sidelink transmitting UE1106to cause the sidelink transmitting UE1106to activate the secondary resource pool. In this manner, the sidelink transmitting UE1106and the sidelink receiving UE1104may transmit and/or receive sidelink communication on the resources of the secondary resource pool. In some examples, when the sidelink transmitting UE1106transmits the sidelink activation indication1114to the sidelink receiving UE1104, each of the sidelink UEs1104,1106may start monitoring for sidelink communication from the other sidelink UE on the resources associated with the primary resource pool and the activated secondary sidelink pool.

FIG.12is a flowchart1200of a method of wireless communication. The method may be performed by a sidelink device such as a UE (e.g., the UE104; the apparatus1302). Optional aspects are illustrated with a dashed line. The method may enable a sidelink device to more efficiently use frequency resources and to improve battery use of sidelink devices.

At1202, the first sidelink device identifies a configuration of a BWP for sidelink communication. The BWP may include aspects described in connection withFIG.9. The BWP may include at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources. The first resource pool may include a primary resource pool, and the second resource pool may include a secondary resource pool. For example, the first resource pool may include a primary resource pool with the first subset of frequency resources that are activated, and the second resource pool may include a secondary resource pool with the second subset of frequency resources that are capable of being activated and deactivated, such as described in connection withFIG.9. The identification of the BWP may be performed by the BWP component1340of the apparatus1302inFIG.13. In some aspects, the first sidelink device may receive the configuration of the BWP, e.g., in a wireless message from another wireless device. In other aspects, the first sidelink device may identify the BWP without receiving a configuration in a wireless message. In some aspects, the first sidelink device may identify a single BWP for the sidelink communication.

At1204, the first sidelink device receives an activation indication activating the second subset of frequency resources of the second resource pool. The reception of the activation indication may be performed, e.g., by the indication component1342via the reception component1330of the apparatus1302inFIG.13. In some aspects, the first sidelink device may receive the activation indication in the first subset of frequency resources of the first resource pool, e.g., and may not receive the activation indication in the second subset of frequency resources of the second resource pool. The BWP may include multiple secondary resource pools including respective subsets of frequency resources that are capable of being activated and deactivated, and the activation indication may activate and/or deactivate frequency resources of at least one of the multiple secondary resource pools.

The first sidelink device may receive the activation indication from another sidelink device. The other sidelink device may be another UE. The first sidelink device may receive the activation indication from the second sidelink device via sidelink. In some aspects, the first sidelink device may receive the activation indication in L1 or L2 signaling from the sidelink device. The activation indication may comprise, or may be comprised in, at least one of sidelink control information, a sidelink wake-up signal, a sidelink MAC-CE, or sidelink RRC signaling. The sidelink activation may be from a transmitting UE, which may have been triggered by L1 or L2 signaling from a base station, such as described in connection withFIG.11. The activation may be received in SCI. The SCI may schedule sidelink resources in the primary resource pool and/or the secondary resource pool. In some aspects, if the activation command is received in SCI, the SCI may schedule a sidelink transmission using resources in the primary (i.e., first) resource pool and not in the secondary (i.e., second) resource pool.

In some aspects, the first sidelink device may receive the activation indication from a base station via an access link. In some aspects, the first sidelink device may receive the activation indication in L1 or L2 signaling from the base station. The activation indication may comprise, or be comprised in, at least one of downlink control information, a downlink wake-up signal, a downlink MAC-CE, or downlink radio resource control signaling. In some aspects, DCI may schedule a sidelink grant in the new resource pool, e.g., the active second resource pool. The base station may use DCI format 3_x (e.g., 3_0 or 3_1) to indicate the activation of the second resource pool (e.g., for a sidelink transmitting UE) and may schedule a SL grant indicating a set of frequency resources in the second resource pool for the transmitting UE to transmit one or more sidelink packet to a sidelink receiving UE.

At1208, the first sidelink device activates the second subset of frequency resources of the second resource pool based on the activation indication. The activation may be performed, e.g., by the resource activation component1346of the apparatus1302inFIG.13.

In some aspects, as illustrated at1206, the first sidelink device may transmit a feedback message to the second sidelink device acknowledging receipt of the activation indication. The first sidelink device may activate the second subset of frequency resources of the second resource pool, at1308, after transmitting the feedback message. The transmission of the feedback may be performed, e.g., by the feedback component1344via the transmission component1334of the apparatus1302inFIG.13. The first sidelink device may transmit the feedback message using the first subset of frequency resources of the first resource pool. The activation indication may comprise SCI that does not schedule a data transmission (e.g., that foregoes scheduling a data transmission. The first wireless device may transmit the feedback message, at1206, to the second sidelink device after decoding the SCI, the feedback message acknowledging receipt of the activation indication. In other aspects, the activation indication may comprise SCI scheduling a data transmission, and the first wireless device may transmit the feedback message, at1206, to the second sidelink device after attempting to decode the data transmission. The feedback message may acknowledge receipt of the activation indication and a decoding status of the data transmission.

In some aspects, as illustrated at1210, the first sidelink device may monitor the second subset of frequency resources for a sidelink transmission from a second sidelink device based on the activating of the second subset of frequency resources of the second resource pool. The monitoring may be performed, e.g., by the monitor component1348of the apparatus1302inFIG.13. For example, the first sidelink device may monitor for the sidelink transmission in one or more active resource pools of the BWP and may forego monitoring (e.g., may skip monitoring or may not monitor) for the sidelink transmission in frequency resources outside the one or more active resources pools of the BWP.

In some aspects, as illustrated at1212, the first sidelink device may transmit a second activation indication to the second sidelink device, the second activation indication activating a third subset of frequency resources of a third resource pool of the BWP. The third subset of frequency resources may be capable of being activated and deactivated, e.g., similar to the second subset of frequency resources. The second resource pool may be the same as the third resource pool, in some aspects. In other aspects, the second resource pool may be different than the third resource pool. The transmission of the second activation indication may be performed, e.g., by the indication component1342via the transmission component1334of the apparatus1302inFIG.13.

As illustrated at1214, the first sidelink device may transmit a second sidelink transmission to the second sidelink device using the third subset of frequency resources of the third resource pool. The transmission may be performed, e.g., by the sidelink communication component1350via the transmission component1334of the apparatus1302.

In some aspects, as illustrated at1224, the first sidelink device may deactivate the second subset of frequency resources of the second resource pool based on an occurrence of a deactivation event. The deactivation, and/or the detection of the occurrence of the deactivation event, may be performed, e.g., by the deactivation component1354of the apparatus1302inFIG.13.

In some aspects, as illustrated at1216, the first sidelink device may receive a deactivation indication. The occurrence of the deactivation event, which triggers the deactivation at1224, may be based on the first sidelink device receiving the deactivation indication. The reception of the deactivation indication may be performed by the indication component1342via the reception component1330of the apparatus1302inFIG.13. The first sidelink device may receive the deactivation indication from the second sidelink device, and the deactivation indication may comprise, or be comprised in, at least one of sidelink control information, a wake-up signal, a sidelink MAC-CE, or sidelink radio resource control signaling. The first sidelink device may receive the deactivation indication from a base station, and the deactivation indication may comprise, or be comprised in, at least one of downlink control information, a downlink wake-up signal, a downlink MAC-CE, or downlink radio resource control signaling. The first sidelink device may receive the deactivation indication in the first subset of frequency resources of the first resource pool or the second subset of frequency resource of the second resource pool.

In some aspects, as illustrated at1218, the first sidelink device may transmit a feedback message to the second sidelink device acknowledging receipt of the deactivation indication. The first sidelink device may deactivate the second subset of frequency resources of the second resource pool, at1224, after transmitting the feedback message. The transmission of the feedback may be performed, e.g., by the feedback component1344via the transmission component1334of the apparatus1302inFIG.13. The first sidelink device may transmit the feedback message using the first subset of frequency resources of the first resource pool or the second subset of frequency resources of the second resource pool.

In some aspects, as illustrated at1220, the first sidelink device may initiate a timer after receiving the sidelink transmission in the second subset of frequency resources of the second resource pool. The occurrence of the deactivation event, which triggers the deactivation at1324, may be based on an expiration of the timer. As illustrated at1222, the first sidelink device may re-initiate the timer when a transmission is received in the second subset of frequency resources of the second resource pool. The initiation and/or re-initiation of the timer may be performed by the timer component1352of the apparatus1302inFIG.13.

FIG.13is a diagram1300illustrating an example of a hardware implementation for an apparatus1302. The apparatus1302is a sidelink device, such as a UE, and includes a baseband processor1304(also referred to as a modem) coupled to a RF transceiver1322and one or more subscriber identity modules (SIM) cards1320, an application processor1306coupled to a secure digital (SD) card1308and a screen1310, a Bluetooth module1312, a wireless local area network (WLAN) module1314, a Global Positioning System (GPS) module1316, and a power supply1318. The baseband processor1304communicates through the RF transceiver1322with the UE104and/or BS102/180. The baseband processor1304may include a computer-readable medium/memory. The computer-readable medium/memory may be non-transitory. The baseband processor1304is responsible for general processing, including the execution of software stored on the computer-readable medium/memory. The software, when executed by the baseband processor1304, causes the baseband processor1304to perform the various functions described supra. The computer-readable medium/memory may also be used for storing data that is manipulated by the baseband processor1304when executing software. The baseband processor1304further includes a reception component1330, a communication manager1332, and a transmission component1334. The communication manager1332includes the one or more illustrated components. The components within the communication manager1332may be stored in the computer-readable medium/memory and/or configured as hardware within the baseband processor1304. The baseband processor1304may be a component of the device350and may include the memory360and/or at least one of the TX processor368, the RX processor356, and the controller/processor359. In one configuration, the apparatus1302may be a modem chip and include just the baseband processor1304, and in another configuration, the apparatus1302may be the entire wireless device (e.g., see350ofFIG.3) and include the additional modules of the apparatus1302.

The communication manager1332includes a BWP component1340that is configured to identify a configuration of a BWP for sidelink communication, e.g., as described in connection with1202. The communication manager1332further includes an indication component1342that is configured to receive and/or transmit an indication to activate or deactivate a subset of frequency resources of a secondary resource pool, e.g., as described in connection with any of1204,1212, and/or1216inFIG.12. The communication manager1332further includes a feedback component1344that is configured to transmit feedback, e.g., as described in connection with1206and/or1218inFIG.12. The communication manager1332further includes a resource activation component1346that is configured to activate the second subset of frequency resources based on the activation indication, e.g., as described in connection with1208inFIG.12. The communication manager1332further includes a monitor component1348that is configured to monitor the second subset of frequency resources for a sidelink transmission from a second sidelink device based on the activating of the second resource pool, e.g., as described in connection with1210inFIG.12. The communication manager1332further includes a sidelink communication component1350that is configured to transmit a second sidelink transmission to the second sidelink device using the third subset of frequency resources of the third resource pool, e.g., as described in connection with1214inFIG.12. The communication manager1332further includes a timer component1352that is configured to initiate and/or re-initiate a timer, e.g., as described in connection with1220and/or1222inFIG.12. The communication manager1332further includes a deactivation component1354that is configured to deactivate the second subset of frequency resources of the second resource pool based on the occurrence of the deactivation event, e.g., as described in connection with1224inFIG.12.

In one configuration, the apparatus1302, and in particular the baseband processor1304, includes means for identifying a configuration of a bandwidth part (BWP) for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources; means for receiving an activation indication activating the second subset of frequency resources of the second resource pool; and means for activating the second subset of frequency resources of the second resource pool based on the activation indication. The apparatus1302may further include means for monitoring the second subset of frequency resources for a sidelink transmission from a second sidelink device based on the activating of the second resource pool. The apparatus1302may further include means for transmitting a feedback message to the second sidelink device acknowledging receipt of the activation indication. The means for transmitting the feedback message may be configured to transmit the feedback message to the second sidelink device after decoding the SCI, the feedback message acknowledging receipt of the activation indication. The means for transmitting the feedback message may be configured to transmit feedback message to the second sidelink device after attempting to decode the data transmission, the feedback message acknowledging receipt of the activation indication and a decoding status of the data transmission. The apparatus1302may further include means for deactivating the second subset of frequency resources of the second resource pool based on an occurrence of a deactivation event. The apparatus1302may further include means for receiving a deactivation indication, wherein the occurrence of the deactivation event comprises the first sidelink device receiving the deactivation indication. The apparatus1302may further include means for transmitting a feedback message to the second sidelink device acknowledging receipt of the deactivation indication. The apparatus1302may further include means for initiating a timer after receiving the sidelink transmission in the second subset of frequency resources of the second resource pool, wherein the occurrence of the deactivation event comprises an expiration of the timer. The apparatus1302may further include means for re-initiating the timer when a transmission is received in the second subset of frequency resources of the second resource pool. The apparatus1302may further include means for transmitting a second activation indication to the second sidelink device, the second activation indication activating a third subset of frequency resources of a third resource pool of the BWP, the third subset of frequency resources capable of being activated and deactivated; and means for transmitting a second sidelink transmission to the second sidelink device using the third subset of frequency resources of the third resource pool.

The aforementioned means may be one or more of the aforementioned components of the apparatus1302configured to perform the functions recited by the aforementioned means. As described supra, the apparatus1302may include the TX Processor368, the RX Processor356, and the controller/processor359. As such, in one configuration, the aforementioned means may be the TX Processor368, the RX Processor356, and the controller/processor359configured to perform the functions recited by the aforementioned means.

FIG.14is a flowchart1400of a method of wireless communication. The method may be performed by a base station (e.g., the base station102,180, the first wireless communication device310; the apparatus1502). Optional aspects are illustrated with a dashed line. The method may enable the base station to assist a sidelink device in more efficient use of frequency resources and reduced battery use.

At1402, the base station identifies a configuration of a BWP for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources. The BWP may include aspects described in connection withFIG.9. The BWP may include at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources. The first resource pool may include a primary resource pool, and the second resource pool may include a secondary resource pool. For example, the first resource pool may include a primary resource pool with the first subset of frequency resources that are activated, and the second resource pool may include a secondary resource pool with the second subset of frequency resources that are capable of being activated and deactivated, such as described in connection withFIG.9. The identification of the BWP may be performed by the sidelink BWP component1540of the apparatus1502inFIG.15. In some aspects, the base station may transmit the configuration of the BWP, e.g., in a wireless message from a sidelink device. In other aspects, the base station may identify the BWP without transmitting a configuration in a wireless message. In some aspects, the base station may identify a single BWP for the sidelink communication.

At1404, the base station transmits an activation indication activating the second subset of frequency resources of the secondary resource pool. The transmission of the activation indication may be performed, e.g., by the activation component1542via the transmission component1534of the apparatus1502inFIG.15. The base station may transmit the activation indication to the sidelink device via an access link. The activation indication may comprise, or be comprised in, at least one of downlink control information, a downlink wake-up signal, a downlink MAC-CE, or downlink radio resource control signaling. The BWP may include multiple secondary resource pools, and the activation indication may activate, and/or deactivate, resources at least one of the second secondary resource pools.

In some aspects, as illustrated at1406, the base station may receive a feedback message from the sidelink device acknowledging receipt of the activation indication. The reception of the feedback may be performed, e.g., by the feedback component1546via the reception component1530of the apparatus1502inFIG.15. The base station may receive the feedback message using the first subset of frequency resources of the first resource pool.

In some aspects, as illustrated at1408, the base station may transmit a deactivation indication to the sidelink device, the deactivation indication deactivating the second subset of frequency resources of the second resource pool. The transmission of the deactivation indication may be performed, e.g., by the deactivation component1544via the transmission component1534of the apparatus1502inFIG.15. The base station may transmit the deactivation indication in at least one of downlink control information, a downlink wake-up signal, a downlink MAC-CE, or downlink RRC signaling. The base station may transmit the deactivation indication in the first subset of frequency resources of the first resource pool or the second subset of frequency resource of the second resource pool.

In some aspects, as illustrated at1410, the base station may receive a feedback message acknowledging receipt of the deactivation indication. The reception of the feedback may be performed, e.g., by the feedback component1546via the reception component1530of the apparatus1502inFIG.15. The base station may receive the feedback message using the first subset of frequency resources of the first resource pool or the second subset of frequency resources of the second resource pool.

FIG.15is a diagram1500illustrating an example of a hardware implementation for an apparatus1502. The apparatus1502is a BS and includes a baseband unit1504. The baseband unit1504may communicate through a cellular RF transceiver1522with the UE104. The baseband unit1504may include a computer-readable medium/memory. The baseband unit1504is responsible for general processing, including the execution of software stored on the computer-readable medium/memory. The software, when executed by the baseband unit1504, causes the baseband unit1504to perform the various functions described supra. The computer-readable medium/memory may also be used for storing data that is manipulated by the baseband unit1504when executing software. The baseband unit1504further includes a reception component1530, a communication manager1532, and a transmission component1534. The communication manager1532includes the one or more illustrated components. The components within the communication manager1532may be stored in the computer-readable medium/memory and/or configured as hardware within the baseband unit1504. The baseband unit1504may be a component of the first wireless communication device310and may include the memory376and/or at least one of the TX processor316, the RX processor370, and the controller/processor375.

The communication manager1532includes a sidelink BWP component1540that is configured to identify a configuration of a BWP for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources, e.g., as described in connection with1402inFIG.14. The communication manager1532further includes an activation component1542that is configured to transmit an activation indication activating the second subset of frequency resources of the secondary resource pool, e.g., as described in connection with1404inFIG.14. The communication manager1532further includes a deactivation component1544that is configured to transmit a deactivation indication to the sidelink device, the deactivation indication deactivating the second subset of frequency resources of the second resource pool, e.g., as described in connection with1408inFIG.14. The communication manager1532further includes a feedback component1546that is configured to receive a feedback message acknowledging receipt of the activation and/or deactivation indication, e.g., as described in connection with1406and/or1410inFIG.14.

In one configuration, the apparatus1502, and in particular the baseband unit1504, includes means for identifying identifies a configuration of a BWP for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources; and means for transmitting an activation indication activating the second subset of frequency resources of the secondary resource pool. The apparatus1502may further include means for receiving a feedback message from the sidelink device acknowledging receipt of the activation indication. The apparatus1502may further include means for a deactivation indication to the sidelink device, the deactivation indication deactivating the second subset of frequency resources of the second resource pool. The apparatus1502may further include means for receiving a feedback message from the sidelink device acknowledging receipt of the deactivation indication.

The aforementioned means may be one or more of the aforementioned components of the apparatus1502configured to perform the functions recited by the aforementioned means. As described supra, the apparatus1502may include the TX Processor316, the RX Processor370, and the controller/processor375. As such, in one configuration, the aforementioned means may be the TX Processor316, the RX Processor370, and the controller/processor375configured to perform the functions recited by the aforementioned means.

FIG.16is a flowchart1600of a method of wireless communication. The method may be performed by a sidelink device such as a UE (e.g., the UE104; the apparatus1302). Optional aspects are illustrated with a dashed line. The method may enable a sidelink device to more efficiently use frequency resources and to improve battery use of sidelink devices.

At1604, the first sidelink device identifies a configuration of a BWP for sidelink communication. The BWP may include aspects described in connection withFIG.9. The BWP may include at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources. The first resource pool may include a primary resource pool, and the second resource pool may include a secondary resource pool. For example, the first resource pool may include a primary resource pool with the first subset of frequency resources that are activated, and the second resource pool may include a secondary resource pool with the second subset of frequency resources that are capable of being activated and deactivated, such as described in connection withFIG.9. The identification of the BWP may be performed by the BWP component1740of the apparatus1702inFIG.17. In some aspects, the first sidelink device may receive the configuration of the BWP, e.g., in a wireless message from another wireless device. In other aspects, the first sidelink device may identify the BWP without receiving a configuration in a wireless message. In some aspects, the first sidelink device may identify a single BWP for the sidelink communication.

At1606, the first sidelink device transmits an activation indication to a second sidelink device, the activation indication activating the second subset of frequency resources of the second resource pool. The reception of the activation indication may be performed, e.g., by the indication component1742via the reception component1730of the apparatus1702inFIG.17. In some aspects, the first sidelink device may transmit the activation indication in the first subset of frequency resources of the first resource pool, e.g., and may not transmit the activation indication in the second subset of frequency resources of the second resource pool. The BWP may include multiple secondary resource pools including respective subsets of frequency resources that are capable of being activated and deactivated, and the activation indication may activate and/or deactivate frequency resources of at least one of the multiple secondary resource pools.

The first sidelink device may transmit the activation indication to the second sidelink device via sidelink. In some aspects, the first sidelink device may transmit the activation indication in L1 or L2 signaling to the second sidelink device. The activation indication may comprise, or may be comprised in, at least one of sidelink control information, a sidelink wake-up signal, a sidelink MAC-CE, or sidelink RRC signaling. The activation may be transmitted in SCI. The SCI may schedule sidelink resources in the primary resource pool and/or the secondary resource pool. In some aspects, if the activation command is transmitted in SCI, the SCI may schedule a sidelink transmission using resources in the primary (i.e., first) resource pool and not in the secondary (i.e., second) resource pool.

The sidelink activation may be from a transmitting UE, which may have been triggered by L1 or L2 signaling from a base station, such as described in connection withFIG.11. As illustrated at1602, the first sidelink device may receive a second activation indication from a base station via an access link, the second activation indication activating the second subset of frequency resources of the second resource pool, where the first sidelink device transmits the activation indication to the second sidelink device, at1606, after receiving the second activation indication from the base station. The second activation indication may comprise, or be comprised in, at least one of downlink control information, a downlink wake-up signal, a downlink MAC-CE, or downlink RRC signaling.

In some aspects, as illustrated at1608, the first sidelink device may receive a feedback message from the second sidelink device acknowledging receipt of the activation indication. The first sidelink device may transmit the sidelink transmission in the second subset of frequency resources of the second resource pool, at1610, after receiving the feedback message. The reception of the feedback may be performed, e.g., by the feedback component1744via the reception component1730of the apparatus1702inFIG.17. The first sidelink device may receive the feedback message using the first subset of frequency resources of the first resource pool. The first sidelink device may activate the second subset of frequency resources of the second resource pool after an interval of time after transmitting the activation indication to the second sidelink device.

The activation indication, transmitted at1606, may comprise SCI that does not schedule (e.g., that foregoes scheduling) a data transmission, and the first sidelink device may receive the feedback message, at1608, acknowledging receipt of the activation indication from the second sidelink device.

The activation indication, transmitted at1606, may comprise SCI scheduling a data transmission, and the first sidelink device may receive the feedback message, at1608, based on an attempt to decode the data transmission.

At1610, the first sidelink device transmits a sidelink transmission to the second sidelink device in the second subset of frequency resources of the second resource pool. The transmission may be performed, e.g., by the sidelink communication component1750via the transmission component1734of the apparatus1702inFIG.17. The second activation indication, received at1602, may comprise DCI scheduling a sidelink grant in the second resource pool, and the first sidelink device may transmit the sidelink transmission, at1610, to the second sidelink device based on the sidelink grant.

In some aspects, as illustrated at1626, the first sidelink device may deactivate the second subset of frequency resources of the second resource pool based on an occurrence of a deactivation event. For example, as illustrated at1624, the first sidelink device may transmit a deactivation indication to the second sidelink device based on the occurrence of the deactivation event, the deactivation indication deactivating the second subset of frequency resources of the second resource pool. The deactivation may be performed by the deactivation component1754of the apparatus1702, and the transmission of the deactivation indication may be performed by the indication component1742via the transmission component1734of the apparatus1702inFIG.17. The deactivation indication may comprise at least one of sidelink control information, a sidelink wake-up signal, a sidelink MAC-CE, or sidelink radio resource control signaling. The first sidelink UE may transmit the deactivation indication to the second sidelink UE in the first subset of frequency resources of the first resource pool or the second subset of frequency resources of the second resource pool.

In some aspects, as illustrated at1628, the first sidelink device may receive a feedback message from the second sidelink device acknowledging receipt of the deactivation indication, and the first sidelink device may receive the feedback message in the first subset of frequency resources of the first resource pool or the second subset of frequency resources of the second resource pool. The reception of the feedback may be performed, e.g., by the feedback component1744via the reception component1730of the apparatus1702inFIG.17.

In some aspects, as illustrated at1616, the first sidelink device may receive a second deactivation indication from a base station, where the occurrence of the deactivation event comprises the first sidelink device receiving the second deactivation indication. The reception of the indication may be performed, e.g., by the indication component1742of the apparatus1702inFIG.17. The second deactivation indication may comprise at least one of downlink control information, a downlink wake-up signal, a downlink MAC-CE, and downlink radio resource control signaling. The first sidelink device may transmit feedback acknowledging the deactivation indication, at1618.

In some aspects, as illustrated at1620, the first sidelink device may initiating a timer after transmitting the sidelink transmission in the second subset of frequency resources of the second resource pool, and the occurrence of the deactivation event may comprise an expiration of the timer. As illustrated at1622, the first sidelink device may reinitiate the timer when a transmission is transmitted in the second subset of frequency resources of the second resource pool. The initiation and re-initiation of the timer may be performed, e.g., by the timer component1752of the apparatus1702inFIG.17.

In some aspects, as illustrated at1612, the first sidelink device may receive a second activation indication from the second sidelink device, the second activation indication activating a third resource pool of the BWP, the third resource pool comprising a third subset of frequency resources capable of being activated and deactivated. The reception of the indication may be performed, e.g., by the indication component1742of the apparatus1702inFIG.17. In some examples, the third subset of frequency resources may be the same as the second subset of frequency resources and/or the third resource pool may be the same as the second resource pool. In other examples, the third subset of frequency resources may be different than the second subset of frequency resources and/or the third resource pool may be different than the second resource pool.

As illustrated at1614, the first sidelink device may receive a second sidelink transmission from the second sidelink device using the third subset of frequency resources of the third resource pool. For example, based on the second activation indication from the second sidelink device, the first sidelink device may monitor the third subset of frequency resources. The reception of the second sidelink transmission may be performed, e.g., by the sidelink communication component1750via the reception component1730of the apparatus1702.

FIG.17is a diagram1700illustrating an example of a hardware implementation for an apparatus1702. The apparatus1702is a sidelink device, such as a UE, and includes a cellular baseband processor1704(also referred to as a modem) coupled to a cellular RF transceiver1722and one or more subscriber identity modules (SIM) cards1720, an application processor1706coupled to a secure digital (SD) card1708and a screen1710, a Bluetooth module1712, a wireless local area network (WLAN) module1714, a Global Positioning System (GPS) module1716, and a power supply1718. The baseband processor1704communicates through the RF transceiver1722with the UE104and/or BS102/180. The baseband processor1704may include a computer-readable medium/memory. The computer-readable medium/memory may be non-transitory. The baseband processor1704is responsible for general processing, including the execution of software stored on the computer-readable medium/memory. The software, when executed by the baseband processor1704, causes the baseband processor1704to perform the various functions described supra. The computer-readable medium/memory may also be used for storing data that is manipulated by the baseband processor1704when executing software. The baseband processor1704further includes a reception component1730, a communication manager1732, and a transmission component1734. The communication manager1732includes the one or more illustrated components. The components within the communication manager1732may be stored in the computer-readable medium/memory and/or configured as hardware within the baseband processor1704. The baseband processor1704may be a component of the device350and may include the memory360and/or at least one of the TX processor368, the RX processor356, and the controller/processor359. In one configuration, the apparatus1702may be a modem chip and include just the baseband processor1704, and in another configuration, the apparatus1702may be the entire wireless device (e.g., see350ofFIG.3) and include the additional modules of the apparatus1702.

The communication manager1732includes a BWP component1740that is configured to identify a configuration of a BWP for sidelink communication, e.g., as described in connection with1604. The communication manager1732further includes an indication component1742that is configured to receive and/or transmit an indication to activate or deactivate a subset of frequency resources of a secondary resource pool, e.g., as described in connection with any of1602,1606,1612,1616and/or1624inFIG.16. The communication manager1732further includes a feedback component1744that is configured to receive or transmit feedback, e.g., as described in connection with1608,1618, and/or1628inFIG.16. The communication manager1732further includes an activation component1746that is configured to activate the second subset of frequency resources based on the activation indication, e.g., in response to the activation indication at1602and/or1612inFIG.16. The communication manager1732further includes a monitor component1748that is configured to monitor the third subset of frequency resources for a sidelink transmission based on the activating of the third resource pool, e.g., as described in connection with1610and1612inFIG.16. The communication manager1732further includes a sidelink communication component1750that is configured to transmit a sidelink transmission to the second sidelink device using the second subset of frequency resources and/or to receive the second sidelink transmission using the third subset of frequency resources of the third resource pool, e.g., as described in connection with1610and/or1614inFIG.16. The communication manager1732further includes a timer component1752that is configured to initiate and/or re-initiate a timer, e.g., as described in connection with1620and/or1622inFIG.16. The communication manager1732further includes a deactivation component1754that is configured to transmit a deactivation indication and/or to deactivate the second subset of frequency resources of the second resource pool based on the occurrence of the deactivation event, e.g., as described in connection with1624and/or1626inFIG.16.

In one configuration, the apparatus1702, and in particular the cellular baseband processor1704, includes means for identifying a configuration of a BWP for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources; means for transmitting an activation indication to a second sidelink device, the activation indication activating the second subset of frequency resources of the second resource pool; and means for transmitting a sidelink transmission to the second sidelink device in the second subset of frequency resources of the second resource pool. The apparatus1702may further include means for receiving a feedback message from the second sidelink device after transmitting the activation indication, and where the first sidelink device transmits the sidelink transmission in the second subset of frequency resources of the second resource pool after receiving the feedback message. The apparatus1702may further include means for receiving a second activation indication from a base station via an access link, the second activation indication activating the second subset of frequency resources of the second resource pool, where the first sidelink device transmits the activation indication to the second sidelink device after receiving the second activation indication from the base station. The apparatus1702may further include means for deactivating the second subset of frequency resources of the second resource pool based on an occurrence of a deactivation event. The apparatus1702may further include means for transmitting a deactivation indication to the second sidelink device based on the occurrence of the deactivation event, the deactivation indication deactivating the second subset of frequency resources of the second resource pool. The apparatus1702may further include means for receiving a feedback message from the second sidelink device acknowledging receipt of the deactivation indication, where the first sidelink device receives the feedback message in the first subset of frequency resources of the first resource pool or the second subset of frequency resources of the second resource pool. The apparatus1702may further include means for receiving a second deactivation indication from a base station, wherein the occurrence of the deactivation event comprises the first sidelink device receiving the second deactivation indication. The apparatus1702may further include means for initiating a timer after transmitting the sidelink transmission in the second subset of frequency resources of the second resource pool, wherein the occurrence of the deactivation event comprises an expiration of the timer. The apparatus1702may further include means for re-initiating the timer when a transmission is transmitted in the second subset of frequency resources of the second resource pool. The apparatus1702may further include means for receiving a second activation indication from the second sidelink device, the second activation indication activating a third resource pool of the BWP, the third resource pool comprising a third subset of frequency resources capable of being activated and deactivated; and means for receiving a second sidelink transmission from the second sidelink device using the third subset of frequency resources of the third resource pool.

The aforementioned means may be one or more of the aforementioned components of the apparatus1702configured to perform the functions recited by the aforementioned means. As described supra, the apparatus1702may include the TX Processor368, the RX Processor356, and the controller/processor359. As such, in one configuration, the aforementioned means may be the TX Processor368, the RX Processor356, and the controller/processor359configured to perform the functions recited by the aforementioned means.

Aspect 1 is a method of wireless communication of a first sidelink device, comprising: identifying a configuration of a BWP for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources; receiving an activation indication activating the second subset of frequency resources of the second resource pool; and activating the second subset of frequency resources of the second resource pool based on the activation indication.

Aspect 2 is the method of aspect 1, further including that the first resource pool comprises a primary resource pool including the first subset of frequency resources that are activated, and the second resource pool comprises a secondary resource pool including the second subset of frequency resources that are capable of being activated and deactivated.

Aspect 3 is the method of any of aspect 1 or aspect 2, further including: monitoring the second subset of frequency resources for a sidelink transmission from a second sidelink device based on the activating of the second subset of frequency resources of the second resource pool.

Aspect 4 is the method of any of aspects 1 to 3, further including that the first sidelink device monitors for the sidelink transmission in one or more active resource pools of the BWP and skips monitoring for the sidelink transmission in frequency resources outside active resources pools of the BWP.

Aspect 5 is the method of any of aspects 1 to 4, further including that the first sidelink device receives the activation indication in the first subset of frequency resources of the first resource pool.

Aspect 6 is the method of any of aspects 1 to 5, further including that the first sidelink device receives the activation indication from a second sidelink device via sidelink.

Aspect 7 is the method of any of aspects 1 to 6, further including that the activation indication comprises at least one of sidelink control information, a sidelink wake-up signal, a sidelink MAC-CE, or sidelink radio resource control signaling.

Aspect 8 is the method of any of aspects 1 to 7, further including: transmitting a feedback message to the second sidelink device acknowledging receipt of the activation indication, wherein the first sidelink device activates the second subset of frequency resources of the second resource pool after transmitting the feedback message.

Aspect 9 is the method of any of aspects 1 to 8, further including that the first sidelink device transmits the feedback message using the first subset of frequency resources of the first resource pool.

Aspect 10 is the method of any of aspects 1 to 9, further including that the activation indication comprises SCI and the SCI does not schedule a data transmission, the method further comprising: transmitting a feedback message to the second sidelink device after decoding the SCI, the feedback message acknowledging receipt of the activation indication.

Aspect 11 is the method of any of aspects 1 to 10, further including that the activation indication comprises SCI scheduling a data transmission, the method further comprising: transmitting a feedback message to the second sidelink device after attempting to decode the data transmission, the feedback message acknowledging receipt of the activation indication and a decoding status of the data transmission.

Aspect 12 is the method of any of aspects 1 to 11, further including that the first sidelink device receives the activation indication from a base station via an access link.

Aspect 13 is the method of any of aspects 1 to 12, further including that the activation indication comprises at least one of downlink control information, a downlink wake-up signal, a downlink MAC-CE, or downlink radio resource control signaling.

Aspect 14 is the method of any of aspects 1 to 13, further including: deactivating the second subset of frequency resources of the second resource pool based on an occurrence of a deactivation event.

Aspect 15 is the method of any of aspects 1 to 14, further including: receiving a deactivation indication, wherein the occurrence of the deactivation event comprises the first sidelink device receiving the deactivation indication.

Aspect 16 is the method of any of aspects 1 to 15, further including that the first sidelink device receives the deactivation indication from a second sidelink device, and wherein the deactivation indication comprises at least one of sidelink control information, a wake-up signal, a sidelink MAC-CE, and sidelink radio resource control signaling.

Aspect 17 is the method of any of aspects 1 to 16, further including that the first sidelink device receives the deactivation indication from a base station, and wherein the deactivation indication comprises at least one of downlink control information, a downlink wake-up signal, a downlink MAC-CE, or downlink radio resource control signaling.

Aspect 18 is the method of any of aspects 1 to 17, further including that the first sidelink device receives the deactivation indication in the first subset of frequency resources of the first resource pool or the second subset of frequency resource of the second resource pool.

Aspect 19 is the method of any of aspects 1 to 18, further including: transmitting a feedback message to a second sidelink device acknowledging receipt of the deactivation indication, wherein the first sidelink device deactivates the second subset of frequency resources of the second resource pool after transmitting the feedback message.

Aspect 20 is the method of any of aspects 1 to 19, further including that the first sidelink device transmits the feedback message using the first subset of frequency resources of the first resource pool or the second subset of frequency resources of the second resource pool.

Aspect 21 is the method of any of aspects 1 to 20, further including: initiating a timer after receiving a sidelink transmission in the second subset of frequency resources of the second resource pool, wherein the occurrence of the deactivation event comprises an expiration of the timer.

Aspect 22 is the method of any of aspects 1 to 21, further including: re-initiating the timer when a transmission is received in the second subset of frequency resources of the second resource pool.

Aspect 23 is the method of any of aspects 1 to 22, further including that the BWP comprises multiple secondary resource pools including respective subsets of frequency resources that are capable of being activated and deactivated, and the activation indication activates or deactivates frequency resources of at least one of the multiple secondary resource pools.

Aspect 24 is the method of any of aspects 1 to 23, further including: transmitting a second activation indication to a second sidelink device, the second activation indication activating a third subset of frequency resources of a third resource pool of the BWP, the third subset of frequency resources capable of being activated and deactivated; and transmitting a second sidelink transmission to the second sidelink device using the third subset of frequency resources of the third resource pool.

Aspect 25 is an apparatus for wireless communication including at least one processor coupled to a memory and configured to implement a method as in any of aspects 1 to 24.

Aspect 26 is an apparatus for wireless communication including means for implementing a method as in any of aspects 1 to 24.

Aspect 27 is a computer-readable medium storing computer executable code, where the code, when executed, causes a processor to implement a method as in any of aspects 1 to 24.

Aspect 28 is a method of wireless communication of a first sidelink device, comprising: identifying a configuration of a BWP for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources; transmitting an activation indication to a second sidelink device, the activation indication activating the second subset of frequency resources of the second resource pool; and transmitting a sidelink transmission to the second sidelink device in the second subset of frequency resources of the second resource pool.

Aspect 29 is the method of aspect 28, further including that the first resource pool comprises a primary resource pool including the first subset of frequency resources that are activated, and the second resource pool comprises a secondary resource pool including the second subset of frequency resources that are capable of being activated and deactivated.

Aspect 30 is the method of any of aspect 28 or aspect 29, further including that the first sidelink device transmits the activation indication in the first subset of frequency resources of the first resource pool.

Aspect 31 is the method of any of aspects 28 to 30, further including that the activation indication comprises at least one of sidelink control information, a sidelink wake-up signal, a sidelink MAC-CE, or sidelink radio resource control signaling.

Aspect 32 is the method of any of aspects 28 to 31, further including: receiving a feedback message from the second sidelink device after transmitting the activation indication, and wherein the first sidelink device transmits the sidelink transmission in the second subset of frequency resources of the second resource pool after receiving the feedback message.

Aspect 33 is the method of any of aspects 28 to 32, further including that the first sidelink device activates the second subset of frequency resources of the second resource pool after an interval of time after transmitting the activation indication to the second sidelink device.

Aspect 34 is the method of any of aspects 28 to 33, further including that the first sidelink device receives the feedback message in the first subset of frequency resources of the first resource pool.

Aspect 35 is the method of any of aspects 28 to 34, further including that the activation indication comprises SCI and the SCI does not schedule a data transmission, and the first sidelink device receives the feedback message acknowledging receipt of the activation indication from the second sidelink device.

Aspect 36 is the method of any of aspects 28 to 35, further including that the activation indication comprises SCI scheduling a data transmission, and the first sidelink device receives the feedback message based on an attempt to decode the data transmission.

Aspect 37 is the method of any of aspects 28 to 36, further including: receiving a second activation indication from a base station via an access link, the second activation indication activating the second subset of frequency resources of the second resource pool, wherein the first sidelink device transmits the activation indication to the second sidelink device after receiving the second activation indication from the base station.

Aspect 38 is the method of any of aspects 28 to 37, further including that the second activation indication comprises at least one of downlink control information, a downlink wake-up signal, a downlink MAC-CE, or downlink radio resource control signaling.

Aspect 39 is the method of any of aspects 28 to 38, further including that the second activation indication comprises downlink control information scheduling a sidelink grant in the second resource pool, and wherein the first sidelink device transmits the sidelink transmission to the second sidelink device based on the sidelink grant.

Aspect 40 is the method of any of aspects 28 to 39, further including: deactivating the second subset of frequency resources of the second resource pool based on an occurrence of a deactivation event.

Aspect 41 is the method of any of aspects 28 to 40, further including: transmitting a deactivation indication to the second sidelink device based on the occurrence of the deactivation event, the deactivation indication deactivating the second subset of frequency resources of the second resource pool.

Aspect 42 is the method of any of aspects 28 to 41, further including that the deactivation indication comprises at least one of sidelink control information, a sidelink wake-up signal, a sidelink MAC-CE, or sidelink radio resource control signaling.

Aspect 43 is the method of any of aspects 28 to 42, further including that the first sidelink UE transmits the deactivation indication to the second sidelink UE in the first subset of frequency resources of the first resource pool or the second subset of frequency resources of the second resource pool.

Aspect 44 is the method of any of aspects 28 to 43, further including: receiving a feedback message from the second sidelink device acknowledging receipt of the deactivation indication, and wherein the first sidelink device receives the feedback message in the first subset of frequency resources of the first resource pool or the second subset of frequency resources of the second resource pool.

Aspect 45 is the method of any of aspects 28 to 44, further including: receiving a second deactivation indication from a base station, wherein the occurrence of the deactivation event comprises the first sidelink device receiving the second deactivation indication.

Aspect 46 is the method of any of aspects 28 to 45, further including that the second deactivation indication comprises at least one of downlink control information, a downlink wake-up signal, a downlink MAC-CE, or downlink radio resource control signaling.

Aspect 47 is the method of any of aspects 28 to 46, further including: initiating a timer after transmitting the sidelink transmission in the second subset of frequency resources of the second resource pool, wherein the occurrence of the deactivation event comprises an expiration of the timer.

Aspect 48 is the method of any of aspects 28 to 47, further including: re-initiating the timer when a transmission is transmitted in the second subset of frequency resources of the second resource pool.

Aspect 49 is the method of any of aspects 28 to 48, further including that the BWP comprises multiple secondary resource pools including respective subsets of frequency resources that are capable of being activated and deactivated, and the activation indication activates or deactivates frequency resources at least one of the multiple secondary resource pools.

Aspect 50 is the method of any of aspects 28 to 49, further including: receiving a second activation indication from the second sidelink device, the second activation indication activating a third resource pool of the BWP, the third resource pool comprising a third subset of frequency resources capable of being activated and deactivated; and receiving a second sidelink transmission from the second sidelink device using the third subset of frequency resources of the third resource pool.

Aspect 51 is an apparatus for wireless communication including at least one processor coupled to a memory and configured to implement a method as in any of aspects 28 to 50.

Aspect 52 is an apparatus for wireless communication including means for implementing a method as in any of aspects 28 to 50.

Aspect 53 is a computer-readable medium storing computer executable code, where the code, when executed, causes a processor to implement a method as in any of aspects 28 to 50.

Aspect 54 is a method of wireless communication of a base station, comprising: identifying a configuration of a BWP for sidelink communication, the BWP comprising at least a first resource pool including a first subset of frequency resources and a second resource pool including a second subset of frequency resources; and transmitting an activation indication to a sidelink UE, the activation indication activating the second subset of frequency resources of the second resource pool.

Aspect 55 is the method of aspect 54, further including that the first resource pool comprises a primary resource pool including the first subset of frequency resources that are activated, and the second resource pool comprises a secondary resource pool including the second subset of frequency resources that are capable of being activated and deactivated.

Aspect 56 is the method of any of aspect 54 or aspect 55, further including that the base station transmits the activation indication to a sidelink device via an access link.

Aspect 57 is the method of any of aspects 54 to 56, further including that the activation indication comprises at least one of downlink control information, a downlink wake-up signal, a downlink MAC-CE, or downlink radio resource control signaling.

Aspect 58 is the method of any of aspects 54 to 57, further including: transmitting a deactivation indication to a sidelink device, the deactivation indication deactivating the second subset of frequency resources of the second resource pool.

Aspect 59 is the method of any of aspects 54 to 58, further including that the base station transmits the deactivation indication in at least one of downlink control information, a downlink wake-up signal, a MAC-CE, and downlink radio resource control signaling.

Aspect 60 is the method of any of aspects 54 to 59, further including that the base station transmits the deactivation indication in the first subset of frequency resources of the first resource pool or the second subset of frequency resource of the second resource pool.

Aspect 61 is the method of any of aspects 54 to 60, further including: receiving a feedback message acknowledging receipt of the deactivation indication.

Aspect 62 is the method of any of aspects 54 to 61, further including that the base station receives the feedback message using the first subset of frequency resources of the first resource pool or the second subset of frequency resources of the second resource pool.

Aspect 63 is the method of any of aspects 54 to 62, further including that the BWP comprises multiple secondary resource pools including respective subsets of frequency resources that are capable of being activated and deactivated, and the activation indication activates or deactivates frequency resources at least one of the multiple secondary resource pools.

Aspect 64 is an apparatus for wireless communication including at least one processor coupled to a memory and configured to implement a method as in any of aspects 54 to 63.

Aspect 65 is an apparatus for wireless communication including means for implementing a method as in any of aspects 54 to 63.

Aspect 66 is a computer-readable medium storing computer executable code, where the code, when executed, causes a processor to implement a method as in any of aspects 54 to 63.