Terminal, base station, communications system, and communication method for allocating hybrid automatic repeat request acknowledge resource using control channel
A terminal that communicates with a base station monitors a physical downlink control channel allocated in a physical downlink control channel region and an enhanced physical downlink control channel allocated in a physical downlink shared channel region different from the physical downlink control channel region. If the enhanced physical downlink control channel is detected, the terminal reports response information via a physical uplink control channel resource corresponding to the resource in which the enhanced physical downlink control channel was detected.
1. A terminal apparatus that is configured to and/or programmed to communicate with a base station apparatus, the terminal apparatus comprising:
a downlink control channel detector configured to and/or programmed to detect an Enhanced Physical Downlink Control Channel (EPDCCH), and
a response transmitter configured to and/or programmed to transmit Hybrid Automatic Repeat request (HARQ) response information using a first Physical Uplink Control Channel (PUCCH) resource and a second PUCCH resource for a Physical Downlink Shared Channel (PDSCH) transmission indicated by a detection of the EPDCCH, wherein
the first PUCCH resource is determined on the basis of at least a lowest element index used to construct the EPDCCH and a first value which is a PUCCH resource offset and is determined, within a plurality of values, from a field in downlink control information of the EPDCCH; and
an index of the second PUCCH resource is an index of the first PUCCH resource plus one.
2. A base station apparatus that is configured to and/or programmed to communicate with a terminal apparatus, the base station apparatus comprising:
a physical control information notifier configured to and/or programmed to transmit an Enhanced Physical Downlink Control Channel (EPDCCH), and
a response information receiver configured to and/or programmed to receive Hybrid Automatic Repeat request (HARQ) response information using a first Physical Uplink Control Channel (PUCCH) resource and a second PUCCH resource for a Physical Downlink Shared Channel (PDSCH) transmission associated with the EPDCCH, wherein
the first PUCCH resource is determined on the basis of at least a lowest element index used to construct the EPDCCH and a first value which is a PUCCH resource offset and is determined, within a plurality of values, from a field in downlink control information of the EPDCCH; and
an index of the second PUCCH resource is an index of the first PUCCH resource plus one.
3. A communication method used by a terminal apparatus that is configured to and/or programmed to communicate with a base station apparatus, the communication method comprising:
detecting an Enhanced Physical Downlink Control Channel (EPDCCH), and transmitting Hybrid Automatic Repeat request (HARQ) response information using a first Physical Uplink Control Channel (PUCCH) resource and a second PUCCH resource for a Physical Downlink Shared Channel (PDSCH) transmission indicated by a detection of the EPDCCH, wherein
the first PUCCH resource is determined on the basis of at least a lowest element index used to construct the EPDCCH and a first value which is a PUCCH resource offset and is determined, within a plurality of values, from a field in downlink control information of the EPDCCH; and
an index of the second PUCCH resource is an index of the first PUCCH resource plus one.
4. A communication method used by a base station apparatus that is configured to and/or programmed to communicate with a terminal apparatus, the communication method comprising:
transmitting an Enhanced Physical Downlink Control Channel (EPDCCH), and
receiving Hybrid Automatic Repeat request (HARQ) response information using a first Physical Uplink Control Channel (PUCCH) resource and a second PUCCH resource for a Physical Downlink Shared Channel (PDSCH) transmission associated with the EPDCCH, wherein
the first PUCCH resource is determined on the basis of at least a lowest element index used to construct the EPDCCH and a first value which is a PUCCH resource offset and is determined, within a plurality of values, from a field in downlink control information of the EPDCCH; and
an index of the second PUCCH resource is an index of the first PUCCH resource plus one.