Method and Apparatus for Transmitting Control Signal in Radio Communication System

• US 20110051671A1
• Filed: 04/30/2009
• Published: 03/03/2011
• Est. Priority Date: 04/30/2008
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kwak, Jin Sam, Han, Seung Hee, Chung, Jae Hoon, Lee, Hyun Woo
• Granted Patent: US 8,451,778 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04L 27/2602 Signal structure
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/2636 with FFT or DFT modulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] transmitter or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/003 Arrangements for allocating sub-channels of the transmission path
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals

Abstract

A method and an apparatus of transmitting a control signal in a wireless communicatino system is provided. They generate a first-spread sequence by spreading a modulated sequence in the first slot by using a first orthogonal sequence, generate a second-spread sequence by spreading a modulated sequence in the second slot by using a second orthogonal sequence. The first spread sequence and the second spread sequence are transmitted in a subframe. A length of the first orthogonal sequence is shorter than a length of the second orthogonal sequence, the second orthogonal sequence is generated by removing at least one element included in the first orthogonal sequence, and the at least one element to be removed is identical in every index of the first orthogonal sequence.

Claims

1. A method of transmitting a control signal in a subframe comprising a first slot and a second slot in a time domain in a wireless communication system, the method comprising:

generating a cyclically shifted sequence by cyclically shifting a base sequence by a cyclic shift amount;

generating a modulated sequence on the basis of a modulation symbol representing the control signal and the cyclically shifted sequence;

generating a first-spread sequence by spreading the modulated sequence in the first slot by using a first orthogonal sequence;

generating a second-spread sequence by spreading the modulated sequence in the second slot by using a second orthogonal sequence; and

transmitting the first spread sequence and the second spread sequence in the subframe,

wherein a length of the first orthogonal sequence is shorter than a length of the second orthogonal sequence, the second orthogonal sequence is generated by removing at least one element included in the first orthogonal sequence, and the at least one element to be removed is identical in every index of the first orthogonal sequence.

2. The method of claim 1, wherein the length of the first orthogonal sequence is 4, and the length of the second orthogonal sequence is 3.

3. The method of claim 2, wherein the first orthogonal sequence is selected from sequences [+1 +1 +1 +1], [−

1 +1 −

1 +1], and [+1 −

1 −

1 +1] each of which has a length of 4, and the second orthogonal sequence is selected from sequences [+1 +1 +1], [−

1 +1 −

1], and [+1 −

1 −

1] each of which has a length of 3

4. The method of claim 2, wherein the first orthogonal sequence is selected from sequences [−

1 −

1 +1 +1], [−

1 +1 −

1 +1], and [+1 −

1 −

1 +1] each of which has a length of 4, and the second orthogonal sequence is selected from sequences [−

1 −

1 +1], [−

1 +1 −

1], and [+1 −

1 −

1] each of which has a length of 3.

5. The method of claim 1, wherein the first slot appears before the second slot.

6. The method of claim 1, wherein each slot comprises a plurality of single carrier-frequency division multiple access (SC-FDMA) symbols, and at least one of the SC-FDMA symbols included in the second slot is punctured.

7. The method of claim 1, wherein the control signal is an acknowledgement (ACK)/not-acknowledgement (NACK) signal for hybrid automatic repeat request (HARQ).

8. An apparatus for wireless communication, comprising:

a radio frequency (RF) unit for transmitting a radio signal; and

a processor coupled to the RF unit,

wherein the processor is configured for;

generating a cyclically shifted sequence by cyclically shifting a base sequence by a cyclic shift amount;

generating a modulated sequence on the basis of a modulation symbol representing a control signal and the cyclically shifted sequence;

generating a first-spread sequence by spreading the modulated sequence in a first slot by using a first orthogonal sequence;

generating a second-spread sequence by spreading the modulated sequence in a second slot by using a second orthogonal sequence; and

transmitting the first spread sequence and the second spread sequence in the subframe that includes the first slot and the second slot,

wherein a length of the first orthogonal sequence is shorter than a length of the second orthogonal sequence, the second orthogonal sequence is generated by removing at least one element included in the first orthogonal sequence, and the at least one element to be removed is identical in every index of the first orthogonal sequence.