METHOD AND APPARATUS FOR TRANSMITTING RECEPTION CONFIRMATION IN WIRELESS SYSTEM

• US 20150092715A1
• Filed: 11/25/2014
• Published: 04/02/2015
• Est. Priority Date: 09/28/2010
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: SEO, Dong Youn, KIM, Min Gyu, YANG, Suck Chel, AHN, Joon Kui
• Granted Patent: US 9,385,851 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04B 7/2643 using time-division multiple access [TDMA] H04B7/2615, H04B7/2618 take precedence
• CPC Class Codes: H04L 1/1614 using bitmaps
• CPC Class Codes: H04L 1/1692 Physical properties of the supervisory signal, e.g. acknowledgement by energy bursts
• CPC Class Codes: H04L 1/1861 Physical mapping arrangements for ACK signaling see also H04L5/0053
• CPC Class Codes: H04L 27/361 Modulation using a single or unspecified number of carriers, e.g. with separate stages of phase and amplitude modulation
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition

Abstract

Provided arc a method and an apparatus for transmitting a reception confirmation in a wireless system. A terminal determines at least one downlink sub-frame for ACK/NACK feedback from each of a plurality of serving cells and determines the number of ACK/NACK bits for the plurality of serving cells. The terminal generates bundled ACK/NACK bits by arraying the ACK/NACK bits in the ascending order of the cell index of the plurality of serving cells, and transmits the bundled ACK/NACK bits.

Claims

1. A method of transmitting a reception acknowledgement in a wireless communication system, the method comprising:

determining, by a user equipment (UE), a number of acknowledgement (ACK)/negative-acknowledgement (NACK) bits for a plurality of serving cells;

determining, by the UE, a number of a plurality of downlink subframes for which the UE needs to feedback ACK/NACK bits in each of the plurality of serving cells;

arranging the ACK/NACK bits in an ascending order of cell indexes of the plurality of serving cells such that the ACK/NACK bits include a series of ACK/NACK bits for downlink subframes of a first cell having a lowest cell index and a series of ACK/NACK bits for downlink subframes of a second cell having a cell index next to the lowest cell index; and

transmitting, by the UE, the ACK/NACK bits to a base station.

2. The method of claim 1, wherein the step of arranging the ACK/NACK bits includes:

arranging the series of ACK/NACK bits for downlink subframes of the first serving cell having the lowest cell index; and

appending the series of ACK/NACK bits for the downlink subframes of the second serving cell at the end of the series of the ACK/NACK bits for the first serving cell.

3. The method of claim 2, wherein the lowest cell index is zero.

4. The method of claim 1, further comprising:

determining whether the number of ACK/NACK bits is greater than a specific value.

5. The method of claim 4, wherein if the number of ACK/NACK bits is greater than the specific value, spatial bundling in which a binary AND operation of ACK/NACK bits corresponding to at least two codewords in each subframe is performed is applied to all subframes in all serving cells.

6. The method of claim 1, wherein the wireless communication system is a time division duplex system.

7. The method of claim 1, further comprising:

generating, by the UE, encoded ACK/NACK bits by encoding the ACK/NACK bits; and

generating, by the UE, ACK/NACK symbols by modulating the encoded ACK/NACK bits.

8. The method of claim 7, wherein a number of bits for the encoded ACK/NACK bits is 48 and the encoded ACK/NACK bits are modulated by using quadrature phase shift keying (QPSK).

9. The method of claim 7, wherein the step of transmitting the ACK/NACK bits includes:

spreading the ACK/NACK symbols with orthogonal sequences; and

transmitting the spread ACK/NACK symbols.

10. A user equipment configured for transmitting a reception acknowledgement in a wireless communication system, the user equipment comprising:

a radio frequency unit configured for transmitting a radio signal; and

a processor operatively coupled with the radio frequency unit and configured to;

determine a number of acknowledgement (ACK)/negative-acknowledgement (NACK) bits for a plurality of serving cells;

determine a number of a plurality of downlink subframes for which the user equipment needs to feedback ACK/NACK in each of the plurality of serving cells;

arrange the ACK/NACK bits in an ascending order of cell indexes of the plurality of serving cells such that the arranged ACK/NACK bits include a series of ACK/NACK bits for downlink subframes of a first cell having a lowest cell index and a series of ACK/NACK bits for downlink subframes of a second cell having a cell index next to the lowest cell index; and

transmit the ACK/NACK bits to a base station.

11. The user equipment of claim 10, wherein the arrangement of the ACK/NACK bits includes:

arranging the series of ACK/NACK bits for the downlink subframes of the first serving cell having the lowest cell index; and

appending the series of ACK/NACK bits for the downlink subframes of the second serving cell at the end of the series of the ACK/NACK bits for the first serving cell.

12. The user equipment of claim 11, wherein the lowest cell index is zero.

13. The user equipment of claim 10, wherein the processor is further configured to determine whether the number of ACK/NACK bits is greater than a specific value.

14. The user equipment of claim 13, wherein if the number of ACK/NACK bits is greater than the specific value, spatial bundling in which a binary AND operation of ACK/NACK bits corresponding to at least two codewords in each subframe is performed is applied to all subframes in all serving cells.

15. The user equipment of claim 10, wherein the processor is further configured to:

generate encoded ACK/NACK bits by encoding the ACK/NACK bits; and

generate ACK/NACK symbols by modulating the encoded ACK/NACK bits.

16. The user equipment of claim 15, wherein a number of bits for the encoded ACK/NACK bits is 48 and the encoded ACK/NACK bits are modulated by using quadrature phase shift keying (QPSK).

17. The user equipment of claim 16, wherein the transmitting of the ACK/NACK bits includes:

spreading the ACK/NACK symbols with orthogonal sequences; and

transmitting the spread ACK/NACK symbols.