Systems and methods for frequency-division duplex transmission time interval operation
View Patent ↗A user equipment (UE) is described. The UE includes a processor and memory in electronic communication with the processor. The UE configures shortened transmission time interval (sTTI) for downlink in a serving cell. The UE also determines a downlink (DL) association set for an uplink subframe. The UE further determines a shortened physical uplink control channel (SPUCCH) format or a PUCCH format used in the uplink subframe, on the basis of at least the number of downlink sTTI(s) within the DL association set.
1. A user equipment (UE), comprising:
receiving circuitry configured to receive a physical downlink shared channel (PDSCH); and
transmitting circuitry configured to transmit a physical uplink control channel (PUCCH); wherein
if a downlink (DL) shortened transmission time interval (sTTI) is smaller than an uplink (UL) sTTI, and if a larger-size PUCCH format is configured, (i) a smaller-size PUCCH format is used when one PDSCH is detected and (ii) whether the larger-size PUCCH format thus configured or the smaller-size PUCCH format is used for the UL sTTI which is larger than the DL sTTI depends on the number of detected PDSCH(s).
2. A base station apparatus, comprising:
transmitting circuitry configured to transmit a physical downlink shared channel (PDSCH);
receiving circuitry configured to receive a physical uplink control channel (PUCCH) from a user equipment (UE); and
configuring circuitry configured to configure, for the UE, a downlink (DL) shortened transmission time interval (sTTI) and an uplink (UL) sTTI;
wherein
if the downlink (DL) shortened transmission time interval (sTTI) is smaller than the uplink (UL) sTTI, and if the configuring circuitry further configures a larger-size PUCCH format for the UE, (i) the receiving circuitry receives, from the UE, the PUCCH using a smaller-size PUCCH format when the PUCCH corresponds to one PDSCH and (ii) whether the larger-size PUCCH format thus configured or the smaller-size PUCCH format is used for the UL sTTI which is larger than the DL sTTI depends on the number of detected PDSCH(s).
3. A method for a user equipment (UE), the method comprising:
receiving a physical downlink shared channel (PDSCH); and
transmitting a physical uplink control channel (PUCCH); wherein
if a downlink (DL) shortened transmission time interval (sTTI) is smaller than an uplink (UL) sTTI, and if a larger-size PUCCH format is configured, (i) a smaller-size PUCCH format is used when one PDSCH is detected and (ii) whether the larger-size PUCCH format thus configured or the smaller-size PUCCH format is used for the UL sTTI which is larger than the DL sTTI depends on the number of detected PDSCH(s).
4. A method for a base station apparatus, the method comprising:
transmitting a physical downlink shared channel (PDSCH);
receiving a physical uplink control channel (PUCCH) from a user equipment (UE); and
configuring, for the UE, a downlink (DL) shortened transmission time interval (sTTI) and an uplink (UL) sTTI; wherein
if the downlink (DL) shortened transmission time interval (sTTI) is smaller than the uplink (UL) sTTI, and if the configuring includes configuring a larger-size PUCCH format for the UE, (i) the receiving includes receiving, from the UE, the PUCCH using a smaller-size PUCCH format when the PUCCH corresponds to one PDSCH and (ii) whether the larger-size PUCCH format thus configured or the smaller-size PUCCH format is used for the UL sTTI which is larger than the DL sTTI depends on the number of detected PDSCH(s).