Spectrum efficiency in configured grant
The invention refers to a method ( 400 ) performed by a secondary user equipment, UE, the method comprising determining (s 402 ) a transmission activity of a primary UE on a configured grant, CG, resource that is shared by the primary UE and the secondary UE; and transmitting data (s 404 ) on the CG resource after determining that the primary UE will not transmit or is not transmitting data on the CG; the invention further refers to a corresponding user equipment.
1 . A method performed by a secondary user equipment (UE), the method comprising:
determining a transmission activity of a primary UE on a configured grant (CG) resource that is shared by the primary UE and the secondary UE; and
transmitting data on the CG resource after determining that the primary UE will not transmit or is not transmitting data on the CG resource, wherein determining that the primary UE will not transmit data on the CG resource comprises:
monitoring a physical uplink control channel (PUCCH) resource configured for scheduling request (SR) transmission;
determining that the primary UE has not transmitted an SR;
determining if no further secondary UE having a priority higher than the priority of the secondary UE has transmitted an SR; and
transmitting data on the CG resource in the affirmative.
2 . The method of claim 1 , wherein determining that the primary UE will not transmit data on the CG resource comprises receiving a communication from the primary UE.
3 . The method of claim 1 , wherein determining that the primary UE will not transmit data on the CG resource comprises performing handshaking and/or negotiations with the primary UE.
4 . The method of claim 1 , wherein determining that the primary UE will not transmit data on the CG resource comprises receiving from the primary UE a permission to transmit data on the CG resource in the next transmission occasion (TO).
5 . The method of claim 1 , wherein determining that the primary UE will not transmit data on the CG resource comprises receiving from the primary UE an indication that the primary UE will not transmit data on the CG resource in the next TO.
6 . The method of claim 5 , wherein the indication that the primary UE will not transmit data on the CG resource in the next TO is being determined from a buffer status report (BSR) of the primary UE being received as part of a broadcast or a multicast from the primary UE.
7 . The method of claim 5 , wherein the indication that the primary UE will not transmit data on the CG resource in the next TO indicates that the CG resource will not be occupied by the primary UE for a certain time.
8 . The method of claim 1 , further comprising transmitting an SR prior to transmitting data on the CG resource.
9 . The method of claim 1 , wherein determining that the primary UE is not transmitting data on the CG resource comprises performing a sensing of a transmission activity of the primary UE on the CG resource.
10 . The method of claim 9 , wherein performing the sensing comprises performing a listen before transmission (LBT) procedure or clear channel assessment (CCA).
11 . The method of claim 9 , wherein in case that the secondary UE detects that the primary UE is not transmitting data on the CG, the secondary UE transmits data on the CG resource after a certain offset with respect to a beginning of a TO.
12 . The method of claim 11 , wherein the CG resource is shared by the primary UE, the secondary UE, and a further secondary UE, wherein the secondary UE and the further secondary UE have different priorities, and wherein the certain offset for each of the secondary and the further secondary UE is dependent on the associated priority.
13 . The method of claim 11 , wherein the secondary UE performs a rate matching a transport block to be transmitted on the CG resource in order to compensate for symbols lost for the sensing process.
14 . A secondary user equipment (UE), adapted to:
determine a transmission activity of a primary UE on a configured grant (CG) resource that is shared by the primary UE and the secondary UE; and
transmit data on the CG after determining that the primary UE will not transmit or is not transmitting data on the CG resource, wherein determining that the primary UE will not transmit data on the CG resource comprises:
monitor a physical uplink control channel (PUCCH) resource configured for scheduling request (SR) transmission;
determine that the primary UE has not transmitted an SR;
determine if no further secondary UE having a priority higher than the priority of the secondary UE has transmitted an SR; and
transmit data on the CG resource in the affirmative.