Method and device for executing HARQ in TDD-based wireless communication system

Patent metadata

Field	Value
Publication number	US-9407416-B2
Application number	US-201514924362-A
Country	US
Kind code	B2
Filing date	Oct 27, 2015
Priority date	Mar 21, 2011
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

Abstract

A method for a base station (BS) to perform a hybrid automatic repeat request (HARQ). The BS transmits an uplink (UL) grant for a first subframe of a second serving cell through a first serving cell. The BS receives UL data based on the UL grant in the first subframe, transmits an acknowledgement/non-acknowledgement (ACK/NACK) for the UL data through a physical HARQ indicator channel (PHICH) in subframe i of the first serving cell and receives non-adaptively retransmitted UL data in a second subframe of the second serving cell if a NACK for the UL data has been transmitted through the PHICH in the subframe i of the first serving cell. The first serving cell and the second serving cell use different UL-DL configurations.

First claim

What is claimed is:

1. A method for performing a hybrid automatic repeat request (HARQ), the method performed by a base station (BS) and comprising:
transmitting an uplink (UL) grant for a first subframe of a second serving cell through a first serving cell;
receiving UL data based on the UL grant in the first subframe;
transmitting an acknowledgement/non-acknowledgement (ACK/NACK) for the UL data through a physical HARQ indicator channel (PHICH) in subframe I of the first serving cell; and
receiving non-adaptively retransmitted UL data in a second subframe of the second serving cell if a NACK for the UL data has been transmitted through the PHICH in the subframe I of the first serving cell,
wherein the first serving cell and the second serving cell use different UL-downlink (DL) configurations, and each of the UL-DL configurations is information on which each subframe within a time division duplex (TDD) frame is configured as a UL subframe, a DL subframe or a special subframe, and
wherein if a PHICH resource corresponding to the UL data is not present in the subframe I, the non-adaptively retransmitted UL data is not received in the second subframe of the second serving cell.

2. The method of claim 1 , wherein if a UL grant indicating a retransmission of the UL data is transmitted in the subframe I, UL data which is adaptively retransmitted by a user equipment (UE) is received in the second subframe of the second serving cell.

3. The method of claim 1 , wherein the first serving cell and the second serving cell use two different UL-DL configurations of UL-DL configurations 0-6 shown in a table below:

UL-DL
DL-to-UL

configur-
switch-point
Subframe n

ation
periodicity
0
1
2
3
4
5
6
7
8
9

0
5 ms
D
S
U
U
U
D
S
U
U
U

1
5 ms
D
S
U
U
D
D
S
U
U
D

2
5 ms
D
S
U
D
D
D
S
U
D
D

3
10 ms 
D
S
U
U
U
D
D
D
D
D

4
10 ms 
D
S
U
U
D
D
D
D
D
D

5
10 ms 
D
S
U
D
D
D
D
D
D
D

6
5 ms
D
S
U
U
U
D
S
U
U
 D.

4. The method of claim 1 , wherein the subframe i is a subframe located between the first subframe and the second subframe.

5. A base station (BS), the BS comprising:
a radio frequency (RF) unit configured to transmit and receive radio signals; and
a processor connected with the RF unit,
wherein the processor is configured to:
transmit an uplink (UL) grant for a first subframe of a second serving cell through a first serving cell,
receive UL data based on the UL grant in the first subframe,
transmit an acknowledgement/non-acknowledgement (ACK/NACK) for the UL data through a physical HARQ indicator channel (PHICH) in subframe i of the first serving cell, and
receive non-adaptively retransmitted UL data in a second subframe of the second serving cell if a NACK for the UL data has been transmitted through the PHICH in the subframe i of the first serving cell,

wherein the first serving cell and the second serving cell use different UL-downlink (DL) configurations, and each of the UL-DL configurations is information on which each subframe within a time division duplex (TDD) frame is configured as a UL subframe, a DL subframe or a special subframe, and
wherein if a PHICH resource corresponding to the UL data is not present in the subframe i, the non-adaptively retransmitted UL data is not received in the second subframe of the second serving cell.

6. The BS of claim 5 , wherein if a UL grant indicating a retransmission of the UL data is transmitted in the subframe i, UL data which is adaptively retransmitted by a user equipment (UE) is received in the second subframe of the second serving cell.

7. The BS of claim 5 , wherein the first serving cell and the second serving cell use two different UL-DL configurations of UL-DL configurations 0-6 shown in a table below:

UL-DL
DL-to-UL

configur-
switch-point
Subframe n

ation
periodicity
0
1
2
3
4
5
6
7
8
9

0
5 ms
D
S
U
U
U
D
S

Assignees

• Lg Electronics Inc

Inventors

• Seo Dong Youn
• Kim Min Gyu
• Seo Han Byul
• Ahn Joon Kui
• Yang Suck Chel

Classifications

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04L5/001

  the frequencies being arranged in component carriers · CPC title

• H04L1/1822 Primary

  involving configuration of automatic repeat request [ARQ] with parallel processes · CPC title

• H04L1/1893

  Physical mapping arrangements (physical resource mapping in general H04L5/00) · CPC title

• H04L5/0055 Primary

  Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861) · CPC title