Communication apparatus and retransmission control method

• US 9,509,474 B2
• Filed: 10/19/2015
• Issued: 11/29/2016
• Est. Priority Date: 08/12/2011
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Inventors: Horiuchi, Ayako, Nishio, Akihiko
• Primary Examiner(s): Thompson, Jr., Otis L
• Application Number:
  US14/886,749
• Publication Number:
  US 20160043847A1
• Time in Patent Office: 407 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1822 involving configuration of automatic repeat request [ARQ] with parallel processes
• CPC Class Codes: H04L 1/1854 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 1/1896 ARQ related signaling
• CPC Class Codes: H04L 2001/125 Arrangements for preventing errors in the return channel
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal

Abstract

Provided is a wireless communication device. A PHICH reception unit determines whether a received signal in a PHICH region is an ACK signal or a NACK signal. When doing so, the PHICH reception unit does not receive a PHICH in a subframe in which a terminal monitors an E-PDCCH. A control signal reception unit outputs a retransmission prompting signal to a signal allocation unit when the signal outputted from the PHICH reception unit is a NACK signal and when a UL grant was not detected. Meanwhile, when a UL grant was detected, the control signal reception unit outputs the detected UL grant to the signal allocation unit. The signal allocation unit maps the transmission signal in accordance with the retransmission prompting signal and the UL grant and transmits the transmission signal from a wireless transmission unit.

Claims

1. A communication apparatus comprising:

a physical HARQ indicator channel (PHICH) receiver that, when receiving a PHICH including an ACK or NACK transmitted from another communication apparatus without using cross-carrier scheduling, does not use the PHICH in one or more secondly cells, but uses the PHICH received in a primary cell; and

a retransmission controller that, in operation, controls whether to perform retransmission to the other communication apparatus, based on the received and used PHICH and assignment control information.

2. The communication apparatus according to claim 1, wherein the PHICH receiver, in operation, receives and uses the PHICH in one of two subsets in a channel state information (CSI) measurement set or a mobility measurement set and does not use the PHICH in the other one of the two subsets.

3. The communication apparatus according to claim 1, wherein the PHICH receiver, in operation, receives and uses the PHICH in an MBMS single frequency network (MBSFN) subframe, but does not use the PHICH in a non-MB MBSFN subframe.

4. The communication apparatus according to claim 1, wherein the PHICH receiver, in operation, does not use the PHICH in an MBMS single frequency network (MBSFN) subframe, but receives and uses the PHICH in a non-MBSFN subframe.

5. The communication apparatus according to claim 1, wherein the PHICH receiver, in operation, determines whether to receive and use the PHICH, based on the number of PHICHs.

6. A communication apparatus comprising:

a physical HARQ indicator channel (PHICH) receiver that, when receiving a PHICH including an ACK or NACK transmitted from another communication apparatus without using cross-carrier scheduling, does not a use the PHICH corresponding to a physical uplink shared channel (PUSCH) assigned to one or more secondly cells, but uses the PHICH corresponding to a PUSCH assigned to a primary cell; and

a retransmission controller that, in operation, controls whether to perform retransmission to the other communication apparatus, based on the received and used PHICH and assignment control information.

7. A retransmission control method comprising:

when a first communication apparatus receives a physical HARQ indicator channel (PHICH) including an ACK or NACK transmitted from a second communication apparatus without using cross-carrier scheduling, the first communication apparatus not using the PHICH in one or more secondary cells, but the first communication apparatus using the PHICH received in a primary cell; and

the first communication apparatus controlling whether to perform retransmission to the second communication apparatus, based on the received and used PHICH and assignment control information.

8. A retransmission control method comprising:

when a first communication apparatus receives a physical HARQ indicator channel (PHICH) including an ACK or NACK transmitted from a second communication apparatus without using cross-carrier scheduling, the first communication apparatus not using the PHICH corresponding to a physical uplink shared channel (PUSCH) assigned to one or more secondary cells, but the first communication apparatus using the PHICH corresponding to a PUSCH assigned to a primary cell; and

the first communication apparatus controlling whether to perform retransmission to the second communication apparatus, based on the received and used PHICH and assignment control information.