Systems and methods for enhancement on sidelink power control

Abstract

Systems and methods for sidelink (SL) power control within wireless communication systems are disclosed herein. A user equipment (UE) selects a parameter set to use to calculate a transmit power of one or more channels to be transmitted according to an SL session with a peer UE from a plurality of parameter sets each configured for use according to a distance between the UE and the peer UE. A UE determines whether an SL pathloss based calculation is to be used to calculate a transmit power of a channel according to an SL session with a peer UE, wherein that calculation is configured to be used depending on a distance between the UE and the peer UE. UE selection of a number of physical SL feedback channel (PSFCH) transmissions to match a UE capability and determinations regarding whether to perform PSFCH reception or PSFCH transmission are also discussed.

1 . A method of a user equipment (UE) for sidelink (SL) communication, comprising:
 establishing an SL session with a peer UE; and   selecting a parameter set to use to calculate a transmit power of one or more channels to be transmitted according to the SL session with the peer UE; wherein the parameter set is selected from a plurality of parameter sets that are each configured for use with the one or more channels according to a distance between the UE and the peer UE.   
     
     
         2 . The method of  claim 1 , further comprising:
 calculating the transmit power of the one or more channels using the selected parameter set; and   transmitting the one or more channels at the calculated power according to the SL session with the peer UE.   
     
     
         3 . The method of  claim 1 , wherein the parameter set is selected based on its association with a resource pool having resources used to transmit the one or more channels and that is configured for use with the one or more channels according to the distance between the UE and the peer UE. 
     
     
         4 . The method of  claim 1 , wherein the parameter set is selected based on a PC5 radio resource control (RRC) configuration between the UE and the peer UE that is made according to the distance between the UE and the peer UE. 
     
     
         5 . The method of  claim 1 , further comprising:
 receiving, from the peer UE, a location of the peer UE;   obtaining a location of the UE; and   calculating the distance between the UE and the peer UE based on the location of the UE and the location of the peer UE;   wherein the parameter set is selected based on the calculated distance.   
     
     
         6 . The method of  claim 5 , further comprising sending, to the peer UE, a parameter set indication indicating the selected parameter set. 
     
     
         7 . The method of  claim 1 , further comprising:
 obtaining a location of the UE;   sending, to the peer UE, the location of the UE; and   receiving a parameter set indication from the peer UE, the parameter set indication corresponding to the distance between the UE and the peer UE;   wherein the parameter set is selected using the parameter set indication.   
     
     
         8 . An apparatus of a user equipment (UE) for sidelink (SL) communication, comprising:
 a processor;   a wireless transceiver; and   a memory storing instructions that, when executed by the processor, configure the UE to:
 establish an SL session with a peer UE; and 
 determine whether an SL pathloss based calculation is to be used to calculate a transmit power of one or more channels according to the SL session with the peer UE; wherein the SL pathloss based calculation is configured to be used depending on a distance between the UE and the peer UE. 
   
     
     
         9 . The apparatus of  claim 8 , wherein the instructions, when executed by the processor, further configure the UE to:
 calculate the transmit power of the one or more channels according to the determination whether to use the SL pathloss based calculation; and   transmit the one or more channels at the calculated power according to the SL session with the peer UE.   
     
     
         10 . The apparatus of  claim 8 , wherein the SL pathloss based calculation is used along with a downlink pathloss based calculation to calculate the transmit power of the one or more channels in response to a determination that the SL pathloss based calculation is to be used. 
     
     
         11 . The apparatus of  claim 8 , wherein the instructions, when executed by the processor, further configure the UE to:
 receive, from the peer UE, a location of the peer UE;   obtain a location of the UE; and   calculate a distance between the UE and the peer UE based on the location of the UE and the location of the peer UE;   wherein the SL pathloss based calculation is determined to be used based on the calculated distance.   
     
     
         12 . The apparatus of  claim 11 , wherein the instructions, when executed by the processor, further configure the UE to send, to the peer UE, an SL pathloss based calculation indication indicating whether the SL pathloss based calculation is to be used to calculate the transmit power of the one or more channels. 
     
     
         13 . The apparatus of  claim 8 , wherein the instructions, when executed by the processor, further configure the UE to:
 obtain a location of the UE;   send, to the peer UE, the location of the UE; and   receive an SL pathloss based calculation indication from the peer UE, the SL pathloss based calculation indication corresponding to the distance between the UE and the peer UE;   wherein the SL pathloss based calculation is determined to be used using the SL pathloss based calculation indication.   
     
     
         14 . A method of a user equipment (UE) for prioritizing a subset of a plurality of pending physical sidelink (SL) feedback channel (PSFCH) transmissions, comprising:
 determining that a number of the plurality of pending PSFCH transmissions is greater than a number of PSFCH transmissions that can be sent by the UE;   determining the subset of the plurality of pending PSFCH transmissions to transmit using a plurality of rules; and   transmitting the subset of the plurality of pending PSFCH transmissions.   
     
     
         15 . The method of  claim 14 , wherein the plurality of rules comprises a distance rule that prioritizes PSFCH transmissions of the pending PSFCH transmissions for inclusion in the subset that correspond to data from a peer UE for which there is a long distance between the UE and the peer UE. 
     
     
         16 . The method of  claim 15 , wherein the plurality of rules comprises the distance rule and a second rule; and wherein determining the subset of the plurality of pending PSFCH transmissions to transmit using the plurality of rules comprises applying the distance rule prior to applying the second rule. 
     
     
         17 . The method of  claim 14 , wherein the plurality of rules comprises a data priority rule that prioritizes PSFCH transmissions of the pending PSFCH transmissions for inclusion in the subset according to a priority of data to which the PSFCH transmissions correspond. 
     
     
         18 . The method of  claim 17 , wherein the plurality of rules comprises the data priority rule and a second rule, and wherein determining the subset of the plurality of pending PSFCH transmissions to transmit using one or more priority rules comprises applying the data priority rule prior to applying the second rule. 
     
     
         19 . The method of  claim 14 , wherein the plurality of rules comprises a Hybrid Automatic Repeat Request (HARQ) acknowledgement (HARQ-ACK) rule that prioritizes PSFCH transmissions of the pending PSFCH transmissions for inclusion in the subset that contain HARQ-ACK messages. 
     
     
         20 . The method of  claim 19 , wherein the plurality of rules comprises the HARQ-ACK rule and a second rule, and wherein determining the subset of the plurality of pending PSFCH transmissions to transmit using one or more priority rules comprises applying the HARQ-ACK rule prior to applying the second rule.