This document relates to systems, devices and techniques for wireless communications.
Wireless communication technologies are moving the world toward an increasingly connected and networked society. The rapid growth of wireless communications and advances in technology has led to greater demand for capacity and connectivity. Other aspects, such as energy consumption, device cost, spectral efficiency, and latency are also important to meeting the needs of various communication scenarios. In comparison with the existing wireless networks, next generation systems and wireless communication techniques need to provide support for an increased number of users and devices, as well as support an increasingly mobile society.
Various methods and apparatus for providing resource allocation schemes for sidelink communications are provided.
In one example aspect, a method of wireless communication is disclosed. The method includes receiving, by a first device, based on a receiving beam information, a first sidelink transmission; selecting, based on selection information, a resource set for a second sidelink transmission; and sending, to a second device, the second sidelink transmission based on transmitting beam information.
In yet another example aspect, a wireless communications apparatus comprising a processor is disclosed. The processor is configured to implement methods described herein.
In another example aspect, the various techniques described herein may be embodied as processor-executable code and stored on a computer-readable program medium.
The details of one or more implementations are set forth in the accompanying drawings, and the description below. Other features will be apparent from the description and drawings, and from the claims.
The disclosed technology provides implementations and examples of resource allocation schemes for sidelink transmissions.
The technologies related to sidelink transmissions are developing fast. Based on the latest discussion progress, FR2 (Frequency Range 2) is a hot topic for sidelink transmissions and how to improve the SL (sidelink)-PRS (positioning reference signal) and other signal/channel transmission and reception for sidelink positioning in FR2 are being studied. For the resource allocation of SL-PRS in FR2, the beam management needs to be considered. In addition, the impact of the beam information for the resource allocation method (e.g., mode1 and/or mode2) needs to be considered as well.
The legacy resource allocation methods are based on the time-frequency resources in the resource pool without considering the actual beam effect. Thus, the legacy methods ignore the effect of space on the time-frequency resources. For example, in the resource allocation for mode 2 sidelink transmissions, the transmitting UE cannot judge the spatial beam information of the time-frequency domain resources sent by another UE. According to the legacy methods, there are limitations on the information that the transmitting UE receives regarding the beam information. In fact, according to the legacy methods, any beam related information is not provided to the transmitting UE and the transmitting UE selects the resource allocation independently from the beam information.
Various implementations of the disclosed technology provide resource allocation techniques for sidelink transmissions. Some implementations of the disclosed technology are related to how to perform the resource allocation under FR2 for sidelink transmissions and how to perform sensing procedures under FR2 for sidelink transmissions. The implementations resolve the currently existing problems for sidelink transmissions in FR2, for example, SL-PRS in SL positioning.
The PRS of NR position has been approved, e.g., RAN #94 for Rel-18 positioning. The sidelink of SI has been approved, e.g., RAN #94 for Rel-18 positioning as follows:
In this patent document, the higher layer corresponds to at least one of RRC layer, SL LPP, PC5-RRC, PC5-S, MAC layer or application layer, and the physical layer corresponds to 1-st SCI, 2-ed SCI, SCI for SL-PRS or MAC CE.
In some implementations, beam, beam information, or beam direction have the same or similar concept, which includes at least one of the following: QCL (quasi co-location) state, TCI (transmission configuration indication) state, spatial relationship information, reference signal information, spatial filter information, and precoding information.
In the implementations, beam/beam direction can be a resource. For example, a transmitter spatial filter, a receiver spatial filter, a transmitter precoding, a receiver precoding, an antenna port, an antenna weight vector, or an antenna weight matrix can all be used as beams.
The parameters of QCL include at least one of the following: Doppler shift, Doppler spread, average delay, delay spread, average gain, spatial parameters (spatial Rx parameter), or spatial relationship information.
The beam can support for various transmission or reception methods which include at least one of the following: space division multiplexing or frequency domain/time domain diversity. The transmitted beam or transmission method can be indicated by a reference signal resource index or a spatial relationship index.
The beam or transmission or reception method of a transmission is determined based on the reference signal resource index. Thus, the transmission or reception filter parameters of the transmission are the same as the transmission or reception filter parameters of the reference signal resource indicated by the reference signal resource index.
The spatial relationship may be indicated by reference signals. Thus, the spatial relationship index can also be a reference signal index. The transmitted beam or transmission or reception method is determined based on the reference signal resource index, which means that the demodulated reference signal of the transmission and the reference signal indicated by the reference signal resource index have the same QCL parameters.
Spatial parameters include spatial reception parameters, such as angle of arrival, spatial correlation of received beams, average delay, and correlation of time-frequency channel responses (including phase information).
The spatial relationship for a certain CH/RS, such as SL-PRS in dedicated resource pool, can be relied on the resource pool ID, slot ID, CSI-RS ID, the PSSCH/SL-PRS resource and the pool ID or other combinations of these ID or resource(s).
The channels/reference signals (CH/RS) include at least one of the following: PSFCH, PSSCH, PSCCH, S-SSB, Physical Downlink Shared Channel (PDSCH), Physical Downlink Control Channel (PDCCH), PRS, SL-PRS, Channel State Information Reference Signal (CSI-RS), Channel State Information Interference Measurement Signal (CSI-IM), Demodulation Reference Signal (DMRS), Downlink Demodulation Reference Signal (DL-DMRS), PSCCH DMRS, PSSCH DMRS, Sidelink CSI-RS, Uplink Demodulation Reference Signal, UL DMRS, Sounding Reference Signal (SRS), Phase-Tracking Reference Signals (PTRS), Random Access Channel (RACH), Synchronization Signal (SS), Synchronization Signal Block (SSB or S-SSB), Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS, SL-PSS, or SL-SSS), or PSBCH DMRS.
The beam can be transmitted from LMF (Location Management Function) to BS, and/or BS to UE, and/or UE to BS, and/or BS to BS, and/or UE to LMF, and/or UE to UE. And the beam info can be contained in higher layer (at least one of RRC layer, SL LPP, PC5-RRC, PC5-S, MAC layer or application layer) or physical layer (1-st SCI, 2-ed SCI, SCI for SL-PRS or MAC CE).
In the description below, section headings are used in the present document only to improve readability and do not limit scope of the disclosed embodiments and techniques in each section only to that section. Furthermore, some embodiments are described with reference to Third Generation Partnership Project (3GPP) New Radio (NR) standard (“5G”) for ease of understanding and the described technology may be implemented in different wireless system that implement protocols other than the 5G protocol.
In general, two sidelink resource allocation modes are supported, i.e., Mode 1 and Mode 2. In Mode 1, a sidelink resource in time and frequency domains allocation is provided by a network (e.g., a base station).
The beam can be transmitted from LMF to the base station, and/or the base station to UE, and/or UE to the base station, and/or base station to another base station, and/or UE to LMF, and/or UE to another UE. The beam information can be contained in a higher layer (at least one of RRC layer, SL LPP, PC5-RRC, PC5-S, MAC layer or application layer) or physical layer (1-st SCI, 2-ed SCI, SCI for SL-PRS or MAC CE).
In the implementations, the UE can forward, transmit, and/or receive the beam information based on the UE capability. For example, a UE only can transmit the beam information to the base station and/or to LMF, and/or another UE or combine of them. These UE capabilities need to be indicated using an indicator.
In Mode 2, a UE decides sidelink transmission resource(s) in time and frequency domains in a resource pool.
In this implementation, the higher layer of the UE triggers the UE to perform a sensing procedure. To perform the sensing procedure, the higher layer may provide beam information at the trigger time slot n. Here, the higher layer is the higher layer applied to the UE performing the sensing procedure. The UE performs the sensing procedure based on the beam information and selects a subset of resources for the sidelink transmission. After the sensing procedure, the UE reports a subset of resource to the higher layer from which the higher layer will select resources for a the sidelink transmission. The sidelink transmission may correspond to transmissions of reference signals (RSS), channels (CHs), data etc. In the FR2, the UE transmits the sidelink transmission based on one or more beams. Thus, unlike the sensing under the legacy resource allocation schemes, the sensing procedure under resource allocation mode 2 in FR2 needs to consider the influence of the beams for the resource allocations. The one or more beams have corresponding directions and the directions of the beams may be referred to as the beam information. The beam information can be obtained in various manners. In some implementations, at the trigger time slot n, the higher layer provides the beam information for the resource allocation. In some implementations, the beam information can come from Tx UE or coordination UE (including RX UE).
For the mode 2 resource allocation of FR2, when taking the SL-PRS resource allocation as an example, the beam information can be provided from the higher layer. The beam information includes Tx beam information (Tx beam info) and Rx beam information (Rx beam info). In some implementations, the Tx beam information refers to the beam information used by a UE for its transmitting operation. Thus, for each of the transmitting UE (TxUE) and the receiving UE (RxUE), the Tx beam information can be used for its transmitting operation. In some implementations, the Rx beam information refers to the beam information used by a UE for its receiving operation. Thus, for the transmitting UE (TxUE), the Rx beam information refers to the beam information used by the transmitting UE (TxUE) for its receiving operation. For the receiving UE (RxUE), the Rx beam information refers to the beam information used by the receiving UE (RxUE) for its receiving operation. In the examples, the transmitting and/or receiving by the transmitting UE may refer to the operation to transmit and/or receive signals, information, channels, etc. In this document, signals, information, channels, etc., may be referred to as data.
In resource allocation mode 2, the higher layer can request the UE to determine a subset of resources from which the higher layer will select resources for SL-PRS transmission. To trigger this procedure, in slot n, the higher layer provides the following parameters for this PSSCH/PSCCH transmission:
Although the table above shows that Tx beam information and Rx beam information are provided from the higher layer, other implementations are also possible such that the Tx beam information and Rx beam information are provided in various manners others than the higher layer. In some implementations, other items included in the table above can also be provided through various manners without being limited from the higher layer. Depending on from which Tx beam information and/or Rx beam information is provided, the following cases can occur.
In some implementations of the disclosed technology, the TxUE receives various message/information/channels according to some configured beam information. The TxUE performs resource selection on the message/information/channel to be transmitted based on the configured beam information and selection information. TXUE send the message and/or information and/or channel(s) based on a beam to a RxUE.
In some implementations, the TxUE is (pre-) configured with a beam direction for transmitting the message/information/channel(s) to another UE. Then, based on the beam information and the selection information, which are obtained from high-level configuration or physical layer, the TxUE performs resource selection according to various messages/information/channels received in the sensing window.
In some implementations, the TxUE receives various messages/information/channels according to some configured beam information. Further, sub-weight refinement is performed to be received in the sensing window according to the configured beam. The TxUE receives various messages/information/channels according to certain configured beam information.
The sidelink transmission includes the transmission of a signal and/or data or channel, such as PSCCH, PSSCH, PSFCH, SL-PRS, SCI to indicated SL-PRS, DMRS, CSI-RS.
For the resource allocation mode 2 of FR2, one or more sensing beams have relation(s) with the Tx beam(s). There are certain association relationships between the one or more sensing beams and the resource allocation.
The transmitting UE (TxUE) receives a message based on the sensing beams with the different directions in a sensing window, in physical layer. The set A (a subset of the resources for the sidelink transmission) is obtained based on the selection procedure and is provided to its higher layer. The selection procedure is based on the resource exclusion with the reservations of the resource obtained in the sensing window. Depending on which direction beams the UE uses to obtain the set A, following cases can occur.
In some implementations, the partial directions have some relationship with the transmission beam (Tx beam). For example, the partial directions correspond to transmission beam (Tx beam) direction(s) or the opposite beam direction(s) with the Rx Beam Group (RBG) or others. In some implementations, the partial directions correspond to directions perpendicular to propagation directions.
For Case 1, the transmitting UE (TxUE) performs the sensing procedure based on all the direction beams or wide beams. The UE performs the resource selection procedure based on the sensing results. The transmitting UE (TxUE) can detect the conflicts in the sensing window and obtain the set A. For case 2, the sensing related beam information can be also referred to as the receiving beam. The receiving beam for case 1 means all the received beams. The receiving beam for case 2 can be partial received beams.
For FR2, there are some resource transmissions with certain directions that would not be in the conflict. Examples 1-4 below discuss the sensing procedures without considering the time/frequency resources, while Examples 5 and 6 below discuss the sensing procedures based on the time/frequency resources. The sensing procedures in the Examples 1-4 involve more conflicts between beam directions, while the sensing procedures in the Examples 5 and 6 involve less conflicts between beam directions. In the examples below, the sensing by the transmitting UE (TxUE) is mainly discussed without other UE's sensing.
In this example, the sensing beam adopts one direction and the transmitting beam adopts one direction. Thus, the sensing beam and the transmitting beam have a 1:1 relationship. In this example, the transmitting UE (TxUE) operates based on the Tx beam information and is (pre-) configured with the direction of a Tx beam to RxUE. The transmitting UE (TxUE) proceeds the sensing procedure with sensing beam. The sensing beam may have a direction that is same or opposite or in another relationship with regard to the Tx beam direction. For example, as shown in
The transmitting UE (UEA) selects the resources for SL-PRS2 with the beam 2 direction based on the received resources with the beam 1 direction in the sending window. As shown in
In this example, the sensing beam adopts multiple directions, and the transmitting beam adopts one direction. Thus, the sensing beam and the transmitting beam have a N:1 relationship. In this example, the transmitting UE (TxUE) operates based on the Tx beam information and is (pre-) configured with the direction of the Tx beam to RxUE (Beam2 direction). Then, the transmitting UE (TxUE) uses the same as and/or the opposite to beam direction and/or the one or more nearby beam directions of them to perform the sensing and/or selection procedure. Thus, in this example and other examples, the sensing beam(s) can have one or more directions, which include same or opposite direction of the configured beam direction, directions of nearby beams of the same or opposite direction of the configured beam directions, etc.
The one or more nearby Rx beams can be referred to as RBG (Rx Beam Group) which contain N Rx beams and have similar spatial relations one each other. The sensing procedure can be based on the Rx Beam Group. Since the RBG includes multiple beams, the sensing procedure can be considered as being based on the wide beams. Different and/or same wide beams can be contained in a RBG. The beams in a RBG can be overlapped in space.
The RBG can be transmitted from LMF to the base station, and/or the base station to UE, and/or UE to the base station, and/or the base station to another base station, and/or UE to LMF, and/or UE to UE. The RBG can be defined or (pre-) configured in the higher layer (at least one of RRC layer, SL LPP, PC5-RRC, PC5-S, MAC layer or application layer) or physical layer (1-st SCI, 2-ed SCI, SCI for SL-PRS or MAC CE).
For example, referring to the example shown in
The transmitting UE (UEA) selects the resources for SL-PRS2 with the beam 2 direction based on the reserved resources with the beam x+1 direction in the sending window. The beam x+1 direction is nearby the opposite direction of the beam 2. The transmitting UE (UEA) receives the signals in the sensing window with the beam x+1 and obtains the reserved resource in the selection window. When selecting resources in the selection window, the transmitting UE (UEA) makes the selections to avoid the conflict with these reserved resources for the resource selection of SL-PRS2.
In this example, the sensing beam adopts one direction and the transmitting beam adopts multiple directions. Thus, the sensing beam and the transmitting beam have a 1:M relationship. In this example, the transmitting UE (TxUE) operates based on the Tx beam information and is (pre-) configured with the direction of the Tx beam to RxUE. Then, the transmitting UE (TxUE) obtains the sensing beam direction that is same, opposite, or in another relationship with regard to the Tx beam direction. The transmitting UE (TxUE) can also obtain the one or more nearby beam directions of the Tx beam. Before sending SL-PRS1, the transmitting UE (TxUE) proceeds the sensing and selection procedure based on the sensing beams. The one or more nearby Tx beams can be named as a TBG (Tx Beam Group) which contains N Tx beams. And the beams in a TBG have similar space relations. Based on the sensing procedure, the transmitting UE (TxUE) sends the SL-PRSs to one or more RxUEs with beam(s) in the Tx Beam Group. Different and/or same wide beams can be contained in a TBG. The beams in a TBG can be overlapped in space.
The TBG can be transmitted from LMF to the base station, and/or the base station to UE, and/or UE to the base station, and/or the base station to another base station, and/or UE to LMF, and/or UE to UE. The TBG can be defined or (pre-) configured in the higher layer (at least one of RRC layer, SL LPP, PC5-RRC, PC5-S, MAC layer or application layer) or physical layer (1-st SCI, 2-ed SCI, SCI for SL-PRS or MAC CE).
For example, as shown in
For example, the TxUE sends SL-PRS with one or more beams in the Tx beam group. The TxUE can perform the resource allocation based on the opposite and/or same beam direction. For example, the TxUE sends SL-PRS1 to UEB with the beam1. The resource allocation is based on the opposite and/or same beam to or as the beam 1. The sending UE can send information to multiple UEs. In addition to sending to UEB, it can also send information to UEC on different beams or at different times. In the example, TxUE uses different transmission beams to send to UEB and UEC respectively, and then the two transmission beams are in the same group. At this time, their resource selection can use the same sensing beam. In the example, when the TxUE wants to send SL-PRS2 to UEC with one or more beams which are included in the Tx Beam Group, the resource allocation can also be performed based on the the beam that is opposite and/or same with regard to the direction of beam1. When the TxUE performs the resource allocation, the higher layer provides a Tx beam direction and/or a TBG. The actual beam used for sending the sidelink transmission to another UE is one or more of the beams in the TBG.
In this example, the sensing beam adopts multiple directions and the transmitting beam adopts multiple directions. Thus, the sensing beam and the transmitting beam have a N:M relationship. In this example, the transmitting UE (TxUE) operates based on the Tx beam information and is (pre-) configured with the direction of the Tx beam to RxUE. Then, the transmitting UE (TxUE) obtains the sensing beam direction that is same, opposite, or in another relationship with regard to the Tx beam direction. The transmitting UE (TxUE) can also obtain the one or more nearby beam direction of the sensing beam. Then, the transmitting UE (TxUE) proceeds the sensing and selection procedures based on one or more of these beams.
The one or more nearby Rx beams can be referred to as a RBG (Rx Beam Group) which contains N Rx beams. And the beams in a RBG have similar space relations. The sensing procedure can be based on one or more beams in the Rx Beam Group. Since the RBG includes multiple beams, the sensing procedure can be considered as being based on the wide beams. A RBG can be also seen as one or more wide beam(s) which corresponds to one or more combinations of some beams. The one or more nearby Tx beams can be referred to as a TBG (Tx Beam Group) which contains N Tx beams. The beams in the TBG have similar space relations to one another. Based on the sensing procedure, the transmitting UE (TxUE) sends the SL-PRSs to one or more RxUEs with beam(s) in the Tx Beam Group.
For example, as shown in
In some implementations of the disclosed technology, the TxUE sends SL-PRS with one or more of the Tx beam groups. The TxUE can proceed the resource allocation based on the one or more beams in RBG. The TxUE (UEA) sends SL-PRS1 to UEB with the beam1 which is a beam in a TBG. The resource allocation is based on one or more beams in RBG. When the TxUE sends SL-PRS2 to UEC with one or more beams which are included in the Tx Beam Group, the resource allocation can also be performed based on the one or more beams in RBG. When the TxUE performs the resource allocation, the higher layer provides Tx beam information and/or a Tx beam direction and/or a TBG. The Tx beam information from the higher layer includes at least one of the Tx associated beams (one or more beams in one or more TBGs). The actual beam used for sending the sidelink transmission to another UE is one or more of the beams in the TBGs. In the example, the sensing which is performed based on the RBG is also associated with a TBG. The resource allocation based on the RBG can be used for one or more beams transmission in the TBG.
In some implementations of the disclosed technology, the Tx beam information and/or the Rx beam information and/or the selection information is obtained from physical layer, and the physical layer is at least one of 1-st SCI, 2-ed SCI, SCI for SL-PRS or MAC CE. In the example, a TxUE sends SL-PRS1 to RxUE with beam 1 in slot n−3, and the TxUE sends SL-PRS2 to the RxUE at slot n+3. Before sending the SL-PRS2, the TxUE receives a SCI or another notice message which notify the beam information and/or the changes of beam information. In some examples, TxUE sends SL-PRS2 with a new beam based on the SCI or another notice message. In some examples, the new beam may be not same as the beam1.
In some implementations of the disclosed technology, the TxUE sends SL-PRS as indicated in the SCI. The SCI contains the notice message such as the beam information (such as beam direction(s)) of transmission resource. The transmission beam may refer to the beam used for the present transmission, next transmission, or any other transmission.
For example, the TxUE sends SL-PRS as indicated in the SCI. One bit in SCI indicates whether the beam direction changes or not for the next transmission. When the bit is 1, it indicates that the beam direction has been changed. When the bit is 0, it indicates that the beam has not been changed and that the next transmission would be performed based on the same beam direction as this time. In this patent document, the beam direction can be referred to as beam or beam information.
In the example, the beam direction is represented using the 1-bit indicator in the SCI sent by UEA. In this case, UEB is periodically sending SL-PRS to UEA. When UEB receives the 1-bit indicator with 1, then the UEB can do one of the following procedures:
For example, UEB will resend and modify the sensing and transmitted beam directions accordingly to the adjacent beam directions of the original beam direction.
For example, a UE sends SL-PRS with SCI indicated. One bit in SCI to indicate the beam sweeping for another UE. For example, the UE sends SL-PRS to another UE always with beam1, and at the slot n, the UE uses the bit to notify the change of the transmission beam. Then, the RxUE can perform the beam sweeping, and find a new beam to receive the SL-PRS which is transmitted from the TxUE.
In some implementations, after performing the sensing procedure, the resource set to be used for the sidelink transmission to the RxUE is selected by the TxUE. In some implementations, the resource set is selected by a selecting beam which is unrelated with a transmitting beam obtained from the transmitting beam information. In some implementations, the selecting beam has a spatial relationship that is orthogonal or approximately orthogonal with regard to a Tx beam. In some implementations, the resource set is selected without considering the conflicts in time-frequency domain. In some implementations, the resource set is selected by selecting beams which are related with a transmitting beam. In some implementations, the selecting beam has a spatial relationship that is same as, opposite to, approximately same as, or approximately opposite to a transmitting beam. In some implementations, the resource set is selected by considering conflicts in time-frequency domain.
In this example, as shown in
In this example, as shown in
In this example of
For the legacy Sidelink Channel Busy Ratio (SL CBR) and Sidelink Channel Occupancy Ratio (SL CR) definition, there is no consideration about the beam information. For FR2 SL, there are two methods to define the CR/CBR. For the first method, all the beam directions are used to measure CR/CBR. For the second method, only some related beam directions are used to measure CR/CBR. Thus, there are more than one CR/CBR for a resource pool, which is different from the legacy scheme.
In some implementations, Channel Occupancy Ratio (CR) and the Channel Busy Ratio (CBR) are received from the higher layer. In some implementations, CR and CBR are measured by a UE. When CR and CBR are measured by the UE, the measurement procedure needs some parameters from the higher layer.
The modifications of CR/CBR definitions are suggested as follows:
SL Channel Busy Ratio (SL CBR) measured in slot n is defined as the portion of sub-channels in the resource pool whose SL RSSI measured by the UE exceed a (pre-) configured threshold sensed over a CBR measurement window [n−a, n−1], wherein a is equal to 100 or 100·2μ slots, according to higher layer parameter sl-Time WindowSizeCBR.
When UE is configured to perform partial sensing by higher layers (including when SL DRX is configured), SL RSSI is measured in slots where the UE performs partial sensing and where the UE performs PSCCH/PSSCH/SL-PRS reception within the CBR measurement window. The calculation of SL CBR is limited within the slots for which the SL RSSI is measured.
When UE is configured to receive based on FR2 beams by higher layers or physical layer, SL RSSI is measured in slots where the UE received based on a certain direction FR2 beam or where the UE received based on a certain RBG/wide direction of FR2 beams or where the UE received based on all the FR2 beam directions within the CBR measurement window.
If the number of SL RSSI measurement slots within the CBR measurement window is below a (pre-) configured threshold, a (pre-) configured SL CBR value is used.
The above modification is applicable for: RRC_IDLE intra-frequency, RRC_IDLE inter-frequency, RRC_CONNECTED intra-frequency, RRC_CONNECTED inter-frequency.
In the modification above, the slot index is based on physical slot index.
Sidelink Channel Occupancy Ratio (SL CR) evaluated at slot n is defined as the total number of sub-channels used for its transmissions in slots [n−a, n−1] and granted in slots [n, n+b] divided by the total number of configured sub-channels in the transmission pool over [n−a, n+b].
When UE is configured to receive based on FR2 beams by higher layers or physical layer, the total number of sub-channels/frequency granularity for SL-PRS used for its transmissions in slots [n−a, n−1] and granted in slots [n, n+b] should be based on a certain direction FR2 beam or a certain RBG direction of FR2 beams or all the FR2 beam directions. Then the total number divided by the total number of configured sub-channels in the transmission pool over [n−a, n+b].
The modification is applicable for: RRC_IDLE intra-frequency, RRC_IDLE inter-frequency, RRC_CONNECTED intra-frequency, RRC_CONNECTED inter-frequency.
In the example above, the CR/CBR is defined per beam or per beam group (TBG and/or RBG) or per wide beam/all beams.
For FR2 SL CBR, the CBR is defined per beam. The CBR measurement window is [n−a, n−1], wherein a is equal to m*100 or m*100·2μ slots or other value, according to higher layer parameter sl-Time WindowSizeCBR-FR2, wherein m is the max numbers of UE Tx and/or Rx beams.
For example, for the UE, there are 8 beams at the maximum from the UE capability, which means that m is 8. The higher layer parameter could be as follows:
Based on the longer CBR measurement window length, the measurement accuracy and the original probability of RSSI measurement slot within a certain beam direction can be guaranteed. If not, there may be more RSSI measurement slots number below the (pre-) configured threshold, then the CBR will be meaningless.
If the number of SL RSSI measurement slots within the CBR measurement window is below a (pre-) configured threshold, a (pre-) configured SL CBR value is used. The configured threshold should be modified.
For FR2 SL CR, the CR is defined per beam.
For a certain beam, the total number of sub-channels/frequency granularity of SL-PRS used for its transmissions in slots [n−a, n−1] and granted in slots [n, n+b] divided by the total number of configured sub-channels/frequency granularity of SL-PRS in the transmission pool over [n−a, n+b].
Note: a is a positive integer and b is 0 or a positive integer; a and b are determined by UE implementation with a+b+1=c*1000 or c*1000·2μ slots or other value, according to higher layer parameter sl-TimeWindowSizeCR-FR2, b< (a+b+1)/2, and n+b shall not exceed the last transmission opportunity of the grant for the current transmission, wherein c is the max numbers of UE Tx and/or Rx beams.
For example, for the UE, there are 8 beams at the maximum from the UE capability. That means the m is 8. So the higher layer parameter could be the flowing:
Based on the longer length TimeWindowSizeCR, the measurement accuracy and the original probability of measurement slot within a certain beam direction can be guaranteed. If not, the CR will be meaningless.
FR2 SL CR and/or CRlimit have relation with the priority of PSCCH/PSSCH/SL-PRS/other RS/CH and/or the beam (or TBG) direction(s).
For example, if a UE is configured with higher layer parameter sl-CR-Limit and transmits PSSCH/SL-PRS in slot n with a certain beam (or TBG) direction, the UE shall ensure the following limits for any priority value k;
For different priority value or different beam (or TBG) directions, there are also different SL CR.
The following two cases can be suggested depending on whether CRlimit has a relation with the beam direction(s).
For different beam (or TBG) directions, the nearby beams (or TBG) may be overlapped. Thus, the time-frequency resources of some nearby beams (or TBG) can be seen as having some conflicts, and the same time-frequency resources with different beams cannot be transmitted without conflicts. The legacy CRlimit value is not useful for each beam (or TBG) directions and some beams having relations (“related beams”) need to share the legacy CRlimit value. Thus, for some related beams instead of all the beams using the legacy CR limit value, the CR needs to be measured and compared with the CRlimit. One of the beams' CRlimit would be smaller than the legacy CRlimit value.
For different beam (or TBG) directions, the time-frequency resources may be seen as having no conflicts. Thus, the same time-frequency resources with different beams can be transmitted without conflicts. Thus, the legacy CRlimit value is also useful for each beam (or TBG) directions.
According to the FR2 SL CBR and SL CR definitions, there could be more than one CR/CBR for a UE. So CBR list and/or CR list can be introduced to contain the CR/CBR measurements.
Based on a UE's antenna configuration, the maximum number of beams is fixed, but the UE can transmit or receive the message with a wide beam which is composed of or includes a set of narrow beams. For a wide beam transmission and/or reception, the CR/CBR could be different from the legacy schemes.
For example, in the example as shown in
If UE A transmits SL-PRS1 based on a narrow beam 1, the CR measurement is based on the beam 1 which is included in the CR list and compared with CRlimit 20%.
If UE A transmits SL-PRS2 based on a wide beam A (TBG1 including beam 1, beam 2 and beam 3), the scheme of CR measurement is based on the beam 1, beam 2 and beam 3 respectively, it can get the CR list and then use the total measurement results compared with CRlimit 20%. For this case, if UEA has transmit SL-PRS1 over the 10%, based on the scheme the beam A could cover the SL-PRS1 and only less than by 10% to 20% of CRlimit for beam A.
If UE A transmits SL-PRS3 based on a wide beam B (TBG2 including beam 3 and beam 4), the scheme of CR measurement is based on the beam 3 and beam 4, respectively, and also compared with CRlimit 20%.
For example, in the example of
For the dedicated resource pool of SL-PRS, the CR and/or CBR can be introduced. For the quality of service (QOS), the congestion control for SL only PSSCH were considered. But now for SL-PRS dedicated resource pool, there is no PSSCH and to do CR/CBR measurement should be based on the SL-PRS. Thus, a series of IEs about SL-PRS can be introduced for CR/CBR.
The modifications of IEs are suggested as follows:
Indicates the PSSCH/SL-PRS/RS or CH transmission parameters to be used by the UEs which do not have available CBR measurement results, by means of an index to the corresponding entry in sl-Tx-ConfigIndexList. Value 0 indicates the first entry in sl-Tx-ConfigIndexList. The field is ignored if the UE has available CBR measurement results.
Indicates the CBR ranges to be used by an index to the entry of the CBR range configuration in sl-CBR-RangeConfigList.
Indicates the minimum MCS value and maximum MCS value for the associated MCS table(s). UE shall ignore the minimum MCS value and maximum MCS value used for table of 64QAM indicated in SL-CBR-PriorityTxConfigList-r16 if SL-CBR-PriorityTxConfigList-v1650 is present.
Indicates the upper bound of priority range which is associated with the configurations in sl-CBR-ConfigIndex and in sl-Tx-ConfigIndexList. The upper bounds of the priority ranges are configured in ascending order for consecutive entries of SL-PriorityTxConfigIndex in SL-CBR-PriorityTxConfigList. For the first entry of SL-PriorityTxConfigIndex, the lower bound of the priority range is 1.
If included, it includes the same number of entries, and listed in the same order, as in SL-CBR-PriorityTxConfigList-r16.
Indicates the list of CBR ranges. Each entry of the list indicates in SL-CBR-LevelsConfig the upper bound of the CBR range for the respective entry. The upper bounds of the CBR ranges are configured in ascending order for consecutive entries of sl-CBR-RangeConfigList. For the first entry of sl-CBR-RangeConfigList the lower bound of the CBR range is 0. Value 0 corresponds to 0, value 1 to 0.01, value 2 to 0.02, and so on.
Indicates the maximum limit on the occupancy ratio. Value 0 corresponds to 0, value 1 to 0.0001, value 2 to 0.0002, and so on (i.e. in steps of 0.0001) until value 10000, which corresponds to 1.
Indicates the list of available PSSCH/SL-PRS transmission parameters (such as MCS, sub-channel number, retransmission number and CR limit) configurations.
Indicates PSSCH/SL-PRS transmission parameters.
Indicates the list of available SL-PRS transmission parameters (such as MCS, sub-channel number, retransmission number and CR limit) configurations.
If a UE is configured with higher layer parameter sl-CR-Limit and transmits PSSCH/SL-PRS in slot n, the UE shall ensure the following limits for any priority value k;
where CR (i) is the CR evaluated in slot n-N for the PSSCH/SL-PRS transmissions with ‘Priority’ field in the SCI set to i, and CRLimit(k) corresponds to the high layer parameter sl-CR-Limit that is associated with the priority value k and the CBR range which includes the CBR measured in slot n-N, where N is the congestion control processing time.
Some preferred embodiments may include the following solutions.
The example embodiments above are performed by a first device which sends a sidelink transmission to a second device. Those skilled in the art can understand that the suggested embodiments can be modified and applied to the second device that receives the sidelink transmission from the first device. For example, the suggested embodiments can include a method of wireless communication comprising receiving, by the second device, from the first device, the second sidelink transmission using the selected resource set that is selected as described in this patent document.
The disclosed and other embodiments, modules and the functional operations described in this document can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this document and their structural equivalents, or in combinations of one or more of them. The disclosed and other embodiments can be implemented as one or more computer program products, i.e., one or more modules of computer program instructions encoded on a computer readable medium for execution by, or to control the operation of, data processing apparatus. The computer readable medium can be a machine-readable storage device, a machine-readable storage substrate, a memory device, a composition of matter effecting a machine-readable propagated signal, or a combination of one or more them. The term “data processing apparatus” encompasses all apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, or multiple processors or computers. The apparatus can include, in addition to hardware, code that creates an execution environment for the computer program in question, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them. A propagated signal is an artificially generated signal, e.g., a machine-generated electrical, optical, or electromagnetic signal, that is generated to encode information for transmission to suitable receiver apparatus.
A computer program (also known as a program, software, software application, script, or code) can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a standalone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file in a file system. A program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code). A computer program can be deployed to be executed on one computer or on multiple computers that are located at one site or distributed across multiple sites and interconnected by a communication network.
The processes and logic flows described in this document can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).
Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read only memory or a random access memory or both. The essential elements of a computer are a processor for performing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto optical disks, or optical disks. However, a computer need not have such devices. Computer readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media and memory devices, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto optical disks; and CD ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.
While this document contains many specifics, these should not be construed as limitations on the scope of an invention that is claimed or of what may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this document in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or a variation of a sub-combination. Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results.
Only a few examples and implementations are disclosed. Variations, modifications, and enhancements to the described examples and implementations and other implementations can be made based on what is disclosed.
Number | Date | Country | |
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Parent | PCT/CN2023/090118 | Apr 2023 | WO |
Child | 18767731 | US |