Terminal device, base station device, and communication method

1. A terminal device that communicates with a base station device, the terminal device comprising:

circuitry configured to

receive a first physical downlink shared channel (PDSCH) that is transmitted on a basis of a sub frame which is defined by a predetermined number of symbols, and a second PDSCH that is transmitted on a basis of an extended sub frame which has a smaller number of symbols than a number of symbols corresponding to the sub frame; and

transmit a first hybrid automatic repeat request acknowledgement (HARQ-ACK) that is a feedback for reception of the first PDSCH in a given sub frame, and transmit a second HARQ-ACK that is a feedback for reception of the second PDSCH in a given extended sub frame, wherein

the circuitry transmits the first HARQ-ACK through a first physical uplink control channel (PUCCH), or through a first physical uplink shared channel (PUSCH) in the given sub frame, the given sub frame being a predetermined number sub frames after a sub frame in which the first PDSCH is received,

the circuitry transmits the second HARQ-ACK through a second PUCCH, or through a second PUSCH in the given extended sub frame, the given extended sub frame being a predetermined number of extended sub frames after an extended sub frame in which the second PDSCH is received, and

in a case that the circuitry is to transmit the first HARQ-ACK in a sub frame including the extended sub frame in which the second HARQ-ACK is transmitted, the circuitry is further configured to either

drop the first HARQ-ACK,

transmit the first HARQ-ACK through a second PUCCH, or

transmit the second PUSCH for transmitting the second HARQ-ACK,

so that the first PUCCH or the first PUSCH is not transmitted in a sub frame including an extended sub frame in which the second HARQ-ACK is transmitted.

2. The terminal device according to claim 1 , wherein the second HARQ-ACK is not transmitted in an extended sub frame included in a sub frame in which the first HARQ-ACK is transmitted.

3. The terminal device according to claim 2 , wherein the circuitry is configured to assume that the second HARQ-ACK which can be transmitted in the extended sub frame included in the sub frame in which the first HARQ-ACK is transmitted is not received.

4. The terminal device according to claim 2 , wherein in a case in which the second HARQ-ACK transmitted in the extended sub frame included in the sub frame in which the first HARQ-ACK is transmitted occurs, the circuitry drops the second HARQ-ACK.

5. The terminal device according to claim 2 , wherein in a case in which the second HARQ-ACK transmitted in the extended sub frame included in the sub frame in which the first HARQ-ACK is transmitted occurs, the circuitry transmits the second HARQ-ACK through a first PUCCH or a first PUSCH for transmitting the first HARQ-ACK.

6. The terminal device according to claim 1 , wherein the first HARQ-ACK is not transmitted in a sub frame including an extended sub frame in which the second HARQ-ACK is transmitted.

7. The terminal device according to claim 6 , wherein the circuitry is configured to assume that the first HARQ-ACK which can be transmitted in the sub frame including the extended sub frame in which the second HARQ-ACK is transmitted is not received.

8. The terminal device according to claim 6 , wherein in a case in which the first HARQ-ACK transmitted in the sub frame including the extended sub frame in which the second HARQ-ACK is transmitted occurs, the circuitry drops the first HARQ-ACK.

9. The terminal device according to claim 6 , wherein in a case in which the first HARQ-ACK transmitted in the sub frame including the extended sub frame in which the second HARQ-ACK is transmitted occurs, the circuitry transmits the first HARQ-ACK through a second PUCCH or a second PUSCH for transmitting the second HARQ-ACK.

10. The terminal device according to claim 1 , wherein

the circuitry receives a first physical downlink control channel (PDCCH) for a notification of allocation information of the first PUSCH that is transmitted on the basis of the sub frame,

the circuitry transmits the first PUSCH on a basis of the allocation information, and

the second HARQ-ACK is not transmitted in an extended sub frame included in a sub frame in which the first PUSCH is transmitted.

11. The terminal device according to claim 1 , wherein

the circuitry receives a first PDCCH for a notification of allocation information of the first PUSCH that is transmitted on the basis of the sub frame,

the circuitry transmits the first PUSCH on a basis of the allocation information, and

the first PUSCH is not transmitted in a sub frame including an extended sub frame in which the second HARQ-ACK is transmitted.

12. The terminal device according to claim 1 , wherein

the circuitry receives a second PDCCH for a notification of allocation information of the second PUSCH that is transmitted on the basis of the extended sub frame,

the circuitry transmits the second PUSCH on a basis of the allocation information, and

the second PUSCH is not transmitted in an extended sub frame included in a sub frame in which the first HARQ-ACK is transmitted.

13. The terminal device according to claim 1 , wherein

the circuitry receives a second PDCCH for a notification of allocation information of a second PUSCH that is transmitted on a basis of the extended sub frame,

the circuitry transmits the second PUSCH on a basis of the allocation information, and

the first HARQ-ACK is not transmitted in a sub frame including an extended sub frame in which the second PUSCH is transmitted.

14. A base station device that communicates with a terminal device, the base station device comprising:

circuitry configured to

transmit a first physical downlink shared channel (PDSCH) on a basis of a sub frame which is defined by a predetermined number of symbols, and a second PDSCH on a basis of an extended sub frame which has a smaller number of symbols than a number of symbols corresponding to the sub frame; and

receive a first hybrid automatic repeat request acknowledgement (HARQ-ACK) that is a feedback for reception of the first PDSCH in a given sub frame, and receive a second HARQ-ACK that is a feedback for reception of the second PDSCH in a given extended sub frame, wherein

the circuitry receives the first HARQ-ACK through a first physical uplink control channel (PUCCH), or through a first physical uplink shared channel (PUSCH) in the given sub frame, the given sub frame being a predetermined number sub frames after a sub frame in which the first PDSCH is received,

the circuitry receives the second HARQ-ACK through a second PUCCH, or through a second PUSCH in the given extended sub frame, the given extended sub frame being a predetermined number of extended sub frames after an extended sub frame in which the second PDSCH is received, and

in a case that the circuitry is to receive the first HARQ-ACK in a sub frame including the extended sub frame in which the second HARQ-ACK is received, either

the first HARQ-ACK is dropped,

the first HARQ-ACK is received through a second PUCCH, or

the second PUSCH for receiving the second HARQ-ACK is received,

so that the first PUCCH or the first PUSCH is not received in a sub frame including an extended sub frame in which the second HARQ-ACK is received.

15. A communication method that is used by a terminal device which communicates with a base station device, the communication method comprising:

receiving, by circuitry of the terminal device, a first physical downlink shared channel (PDSCH) that is transmitted on a basis of a sub frame which is defined by a predetermined number of symbols, and a second PDSCH that is transmitted on a basis of an extended sub frame which has a smaller number of symbols than a number of symbols corresponding to the sub frame; and

transmitting, by the circuitry, a first hybrid automatic repeat request acknowledgement (HARQ-ACK) that is a feedback for reception of the first PDSCH in a given sub frame, and transmitting a second HARQ-ACK that is a feedback for reception of the second PDSCH a given extended sub frame, wherein

the transmitting the first HARQ-ACK is through a first physical uplink control channel (PUCCH), or through a first physical uplink shared channel (PUSCH) in the given sub frame, the given sub frame being a predetermined number sub frames after a sub frame in which the first PDSCH is received,

the transmitting the second HARQ-ACK is through a second PUCCH, or through a second PUSCH in the given extended sub frame, the given extended sub frame being a predetermined number of extended sub frames after an extended sub frame in which the second PDSCH is received, and

in a case that the transmitting is to include transmitting the first HARQ-ACK in a sub frame including the extended sub frame in which the second HARQ-ACK is transmitted, the method further comprises either:

dropping the first HARQ-ACK,

transmitting the first HARQ-ACK through a second PUCCH, or

transmitting the second PUSCH for transmitting the second HARQ-ACK,

so that the first PUCCH or the first PUSCH is not transmitted in a sub frame including an extended sub frame in which the second HARQ-ACK is transmitted.

16. A communication method that is used by a base station device which communicates with a terminal device, the communication method comprising:

transmitting by circuitry of the base station, a first physical downlink shared channel (PDSCH) on a basis of a sub frame which is defined by a predetermined number of symbols, and a second PDSCH on a basis of an extended sub frame which has a smaller number of symbols than a number of symbols corresponding to the sub frame; and

receiving a first hybrid automatic repeat request acknowledgement (HARQ-ACK) that is a feedback for reception of the first PDSCH in a given sub frame, and receiving a second HARQ-ACK that is a feedback for reception of the second PDSCH in a given extended sub frame, wherein

the receiving the first HARQ-ACK is through a first physical uplink control channel (PUCCH), or through a first physical uplink shared channel (PUSCH) in the given sub frame, the given sub frame being a predetermined number sub frames after a sub frame in which the first PDSCH is received,

the receiving the second HARQ-ACK is through a second PUCCH, or through a second PUSCH in the given extended sub frame, the given extended sub frame being a predetermined number of extended sub frames after an extended sub frame in which the second PDSCH is received, and

in a case that the receiving is to include receiving the first HARQ-ACK in a sub frame including the extended sub frame in which the second HARQ-ACK is received, either

the first HARQ-ACK is dropped,

the first HARQ-ACK is received through a second PUCCH, or

the second PUSCH for receiving the second HARQ-ACK is received,

so that the first PUCCH or the first PUSCH is not received in a sub frame including an extended sub frame in which the second HARQ-ACK is received.

17. The terminal device according to claim 1 , wherein

in a case that the circuitry is to transmit the second HARQ-ACK in the extended sub frame included in the sub frame in which the first HARQ-ACK is transmitted, the circuitry is further configured to either

drop the second HARQ-ACK,

transmit the second HARQ-ACK through a first PUCCH, or

transmit the first PUSCH for transmitting the first HARQ-ACK,

so that the second PUCCH or the second PUSCH is not transmitted in an extended sub frame included in a sub frame in which the first HARQ-ACK is transmitted.