Systems and methods for semi-persistent scheduling of wireless communications
Methods, systems, and devices for transmission and reception of SPS communications are disclosed herein. User equipment (UE) is configured to receive, in a first subframe, a physical downlink control channel or enhanced physical downlink control channel (PDCCH/EPDCCH) corresponding to semi-persistent scheduling (SPS) activation. The PDCCH/EPDCCH conveys a value of nSCID. The UE configures, based on the SPS activation, a downlink (DL) assignment in a second subframe for receiving an SPS physical downlink shared channel (PDSCH) without a corresponding PDCCH/EPDCCH. The UE determines a reference signal sequence corresponding to the SPS PDSCH using n SCID derived from the PDCCH/EPDCCH corresponding to the associated SPS activation. The UE receives the SPS PDSCH in a second subframe. The UE processes the SPS PDSCH based on the reference signal sequence for the SPS PDSCH in the second subframe using the n SCID derived from the PDCCH/EPDCCH corresponding to the associated SPS activation. The UE is configured for transmission mode 10 (TM 10 ).
1. An apparatus for a user equipment (UE) comprising:
a memory configured to store a value of n SCID ; and
logic, at least a portion of which comprises circuitry, to:
decode a physical downlink control channel or enhanced physical downlink control channel (PDCCH/EPDCCH) corresponding to semi-persistent scheduling (SPS) activation in a first subframe, wherein the PDCCH/EPDCCH conveys a value of n SCID ;
configure, based on the SPS activation, a downlink (DL) assignment in a second subframe that is different than the first subframe, wherein the UE is configured for transmission mode 10 (TM 10 );
identify a UE-specific reference signal in the second subframe, wherein the UE-specific reference signal is associated with an SPS physical downlink shared channel (PDSCH) in the second subframe, wherein the SPS PDSCH is without a corresponding PDCCH/EPDCCH;
determine a reference signal sequence corresponding to the UE-specific reference signal in the second subframe using the value of n SCID derived from the PDCCH/EPDCCH corresponding to SPS activation in the first subframe, wherein to determine the reference signal sequence, the logic is configured to generate the reference signal sequence based on a virtual cell identity of n ID (n SCID ) selected based on the value for n SCID , the virtual cell identity corresponding to the SPS activation; and
process the SPS PDSCH based on the UE-specific reference signal and the reference signal sequence.
2. The apparatus of claim 1 , wherein the UE is configured for coordinated multipoint (CoMP) transmission or reception, and wherein one or more of the SPS PDSCH and the PDCCH/EPDCCH corresponding to SPS activation comprise CoMP transmissions.
3. The apparatus of claim 1 , wherein the logic is further configured to monitor a downlink control information (DCI) format and wherein the value of n SCID is conveyed according to DCI format 2D.
4. The apparatus of claim 1 , wherein the n ID (n SCID ) is configured by signaling on a layer above the physical layer.
5. The apparatus of claim 1 , wherein the PDCCH/EPDCCH corresponding to SPS activation further conveys a value for a PDSCH resource element (RE) mapping quasi co-location indicator (PQI), and wherein the logic is further configured to process the SPS PDSCH based on a transmission parameter set indicated by the value for the PQI.
6. The apparatus of claim 1 , wherein the logic is further configured to process the SPS PDSCH based on a transmission parameter set indicated by a value for a PDSCH resource element (RE) mapping quasi co-location indicator (PQI), wherein the value for the PQI is configured based on RRC layer signaling.