Terminal, base station, communication system, and communication method

A terminal that communicates with a base station, comprising:

• a downlink control channel detection unit that monitors a physical downlink control channel arranged in a physical downlink control channel region and an enhanced physical downlink control channel arranged in a region different from the physical downlink control channel region;
• a data extraction unit that extracts, in a case where the downlink control channel detection unit detects the enhanced physical downlink control channel associated with a physical downlink shared channel on a primary cell and the physical downlink control channel or the enhanced physical downlink control channel associated with a physical downlink shared channel on a secondary cell, transmit data in the physical downlink shared channel on the primary cell and transmit data in the physical downlink shared channel on the secondary cell;
• a response information generation unit that generates response information in response to each of the extracted transmit data;
• a channel selection unit that selects, based on the response information, one physical uplink control channel resource from a physical uplink control channel resource configured for the physical downlink shared channel on the primary cell and a physical uplink control channel resource configured for the physical downlink shared channel on the secondary cell;
• an uplink control channel generation unit that generates a physical uplink control channel based on the response information;
• and
• a response transmission unit that transmits the physical uplink control channel generated by the uplink control channel generation unit, using the physical uplink control channel resource selected by the channel selection unit.

A communication system that performs communication between a base station and a terminal,

• wherein the terminal comprises
• a downlink control channel detection unit that monitors a physical downlink control channel arranged in a physical downlink control channel region and an enhanced physical downlink control channel arranged in a region different from the physical downlink control channel region,
• a data extraction unit that extracts, in a case where the downlink control channel detection unit detects the enhanced physical downlink control channel associated with a physical downlink shared channel on a primary cell and the physical downlink control channel or the enhanced physical downlink control channel associated with a physical downlink shared channel on a secondary cell, transmit data in the physical downlink shared channel on the primary cell and transmit data in the physical downlink shared channel on the secondary cell,
• a response information generation unit that generates response information in response to each of the extracted transmit data,
• a channel selection unit that selects, based on the response information, one physical uplink control channel resource from a physical uplink control channel resource configured for the physical downlink shared channel on the primary cell and a physical uplink control channel resource configured for the physical downlink shared channel on the secondary cell,
• an uplink control channel generation unit that generates a physical uplink control channel based on the response information, and
• a response transmission unit that transmits the physical uplink control channel generated by the uplink control channel generation unit, using the physical uplink control channel resource selected by the channel selection unit, and
• wherein the base station comprises
• a physical control information delivering unit that reports, to the terminal, the enhanced physical downlink control channel associated with the physical downlink shared channel on the primary cell, and the physical downlink control channel or the enhanced physical downlink control channel associated with the physical downlink shared channel on the secondary cell, and
• a response information reception unit that monitors a physical uplink control channel resource configured for the physical downlink shared channel on the primary cell and a physical uplink control channel resource configured for the physical downlink shared channel on the secondary cell, and extracts response information in response to transmit data in the physical downlink shared channel on the primary cell and response information in response to transmit data in the physical downlink shared channel on the secondary cell.

A communication method performed by a terminal that communicates with a base station, comprising:

• a step of monitoring a physical downlink control channel arranged in a physical downlink control channel region and an enhanced physical downlink control channel arranged in a region different from the physical downlink control channel region;
• a step of extracting, in a case where the enhanced physical downlink control channel associated with a physical downlink shared channel on a primary cell and the physical downlink control channel or the enhanced physical downlink control channel associated with a physical downlink shared channel on a secondary cell are detected, transmit data in the physical downlink shared channel on the primary cell and transmit data on the physical downlink shared channel in the secondary cell;
• a step of generating response information in response to each of the extracted transmit data;
• a step of selecting, based on the response information, one physical uplink control channel resource from a physical uplink control channel resource configured for the physical downlink shared channel on the primary cell and a physical uplink control channel resource configured for the physical downlink shared channel on the secondary cell;
• a step of generating a physical uplink control channel based on the response information;
• and
• a step of transmitting the generated physical uplink control channel using the selected physical uplink control channel resource.