# US 9,439,189 B2 · Method and device for transmitting ACK/NACK in carrier aggregating system

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 9,439,189 B2
- Document ID: US9439189B2
- Status: Granted
- Kind: B2
- Application number: 14/378,911
- Filed: 2013-02-20
- Published: 2016-01-21
- Granted: 2016-09-06
- Earliest claimed: 2012-02-20
- Assignees: LG Electronics Inc.
- Applicants: LG Electronics Inc.
- Inventors: Dongyoun Seo; Bonghoe Kim; Joonkui Ahn; Suckchel Yang
- Web page: https://patentgrep.com/patent/US9439189B2

## CPC

- H04W 72/0446: Resources in time domain, e.g. slots or frames
- H04L 1/1829: Arrangements specially adapted for the receiver end
- H04L 5/001: {the frequencies being arranged in component carriers}
- H04L 5/0055: {Physical resource allocation for ACK/NACK (for physical mapping arrangements in ARQ protocols H04L1/1861)}
- H04L 5/14: Two-way operation using the same type of signal, i.e. duplex
- H04L 5/1469: {using time-sharing}
- H04W 76/14: Direct-mode setup
- H04W 76/19: Connection re-establishment
- H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72)
- H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M)

## Abstract

The present invention relates to a method of transmitting an acknowledgement/not-acknowledgement (ACK/NACK) and a device for using such a method. According to the present invention, a cell-specific downlink-uplink setting for one of a plurality of serving cells and a reference UL-DL setting is received, an effective downlink sub-frame capable of actually receiving a data unit from one serving cell is determined based on the settings, and only an ACK/NACK for the effective downlink sub-frame is configured as a bit string and fed back.

## Claims

### Claim 1

A method of transmitting acknowledgement (ACK)/not-acknowledgement (NACK) of a user equipment configured with a plurality of serving cells, the method comprising:
receiving a cell-specific uplink (UL)-downlink (DL) configuration for a secondary cell among the plurality of serving cells,
wherein the cell-specific UL-DL configuration is information which configures subframes in a frame of the secondary cell to a UL subframe or a DL subframe;
receiving a reference UL-DL configuration for the secondary cell,
wherein the reference UL-DL configuration is information which indicates an ACK/NACK transmission time by configuring the subframes in the frame to the UL subframe or the DL subframe;
determining valid DL subframes capable of actually receiving a data unit in the secondary cell on the basis of the cell-specific UL-DL configuration and the reference UL-DL configuration; and
constructing ACK/NACK only for the valid DL subframes in a form of a bit-stream and feed-backing the bit-stream,
wherein the reference UL-DL configuration for the secondary cell is a cell-specific UL-DL configuration for a primary cell, and
wherein, when the primary cell uses a time division duplex (TDD) frame and the secondary cell uses a frequency division duplex (FDD) frame, a DL subframe which overlaps with a UL subframe of the TDD frame among DL subframes included in the FDD frame is excluded from the valid DL subframes.

### Claim 2 (depends on 1)

The method of claim 1, wherein the plurality of serving cells include the primary cell in which the user equipment performs an initial connection establishment procedure or a connection re-establishment procedure with respect to a base station and the secondary cell which is additionally allocated in addition to the primary cell.

### Claim 3 (depends on 1)

The method of claim 1, wherein scheduling information for the secondary cell is received through the primary cell.

### Claim 4 (depends on 3)

The method of claim 3, wherein ACK/NACK for a data unit received in the secondary cell is transmitted through the primary cell.

### Claim 5 (depends on 1)

The method of claim 1, wherein the cell-specific UL-DL configuration and the reference UL-DL configuration are applied respectively for the primary cell and the secondary cell.

### Claim 6 (depends on 5)

The method of claim 5, wherein the reference UL-DL configuration for the primary cell is equal to the reference UL-DL configuration for the secondary cell.

### Claim 7 (depends on 1)

The method of claim 1, wherein the cell-specific UL-DL configuration and the reference UL-DL configuration are selected from UL-DL configurations of the following table
Uplink-
Downlink-
downlink
to-Uplink
configu-
Switch-point
Subframe n
ration
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
7
N/A
D
D
D
D
D
D
D
D
D
D

### Claim 8

A user equipment comprising:
a radio frequency (RF) unit for transmitting and receiving a radio signal; and
a processor operatively coupled to the RF unit,
wherein the processor is configured for:
receiving a cell-specific uplink (UL)-downlink (DL) configuration for a secondary cell among the plurality of serving cells,
wherein the cell-specific UL-DL configuration is information which configures subframes in a frame of the secondary cell to a UL subframe or a DL subframe;
receiving a reference UL-DL configuration for the secondary cell,
wherein the reference UL-DL configuration is information which indicates an ACK/NACK transmission time by configuring the subframes in the frame to the UL subframe or the DL subframe;
determining valid DL subframes capable of actually receiving a data unit in the secondary cell on the basis of the cell-specific UL-DL configuration and the reference UL-DL configuration; and
constructing ACK/NACK only for the valid DL subframes in a form of a bit-stream and feed-backing the bit-stream,
wherein the reference UL-DL configuration for the secondary cell is a cell-specific UL-DL configuration for a primary cell, and
wherein, when the primary cell uses a time division duplex (TDD) frame and the secondary cell uses a frequency division duplex (FDD) frame, a DL subframe which overlaps with a UL subframe of the TDD frame among DL subframes included in the FDD frame is excluded from the valid DL subframes.