Method of transmitting reference signal and transmitter using the same

• US 7,940,643 B2
• Filed: 04/16/2010
• Issued: 05/10/2011
• Est. Priority Date: 03/17/2008
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, Ki Jun, Lee, Jung Hoon, Ahn, Joon Kui, Lee, Daewon
• Primary Examiner(s): Duong; Frank
• Application Number:
  US12/762,027
• Publication Number:
  US 20100195481A1
• Time in Patent Office: 389 Days
• Field of Search: 370203-210, 370328-339
• US Class Current: 370/208
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/262 Reduction thereof by selection of pilot symbols
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method and apparatus of transmitting a reference signal in a wireless communication system is provided. A reference signal sequence is generated by using a pseudo-random sequence. A portion or entirety of the reference signal sequence is mapped to at least one resource block and is transmitted. The pseudo-random sequence is generated by a gold sequence generator which is initialized with initial values obtained by using cell identifier. The reference signal provides low PAPR and high cross correlation characteristic.

Claims

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

initializing, by a transmitter, a first sequence c(i) with an initial value, where i=0, 1, . . . , M_max−

1, and M_max is a length of the first sequence c(i);

generating, by the transmitter, a second sequence based on the first sequence c(i);

mapping, by the transmitter, a portion or entirety of the second sequence to radio resources; and

transmitting, by the transmitter, the mapped second sequence in the radio resources,

wherein the first sequence c(i) is defined by a first m-sequence x(i) and a second m-sequence y(i) as shown;

c(i)=(x(i+Nc)+y(i+Nc))mod 2

x(i+31)=(x(i+3)+x(i))mod 2

y(i+31)=(y(i+3)+y(i+2)+y(i+1)+y(i))mod 2

where Nc is a constant, and

wherein the initial value is obtained on the basis of (2N_ID^cell+1), where N_ID^cell is a cell identifier.

2. The method of claim 1, wherein the first m-sequence x(i) is initialized with x(i)=1 at i=0, x(i)=0 at i=1, 2, . . . , 30, and the second m-sequence y(i) is initialized with the initial value.

3. The method of claim 2, wherein the Nc is a value in range from 1500 to 1800.

4. The method of claim 1, wherein the second sequence is used for a reference signal.

5. The method of claim 1, wherein the first sequence is applied as a scrambling sequence to generate the second sequence.

6. A transmitter configured to transmit a sequence in a wireless communication system, the transmitter comprising:

a generator configured to generate a second sequence based on a first sequence c(i), where i=0, 1, . . . , M_max−

1, and M_max is a length of the first sequence c(i); and

a transmit circuit configured to transmit the second sequence,

wherein the first sequence c(i) is defined by a first m-sequence x(i) and a second m-sequence y(i) as shown;

c(i)=(x(i+Nc)+y(i+Nc))mod 2

x(i+31)=(x(i+3)+x(i))mod 2

y(i+31)=(y(i+3)+y(i+2)+y(i+1)+y(i))mod 2

where Nc is a constant, and

wherein the first sequence c(i) is initialized with an initial value obtained on the basis of (2N_ID^cell+1), where N_ID^cell is a cell identifier.

7. The transmitter of claim 6, wherein the first m-sequence x(i) is initialized with x(i)=1 at i=0, x(i)=0 at i=1, 2, . . . , 30, and the second m-sequence y(i) is initialized with the initial value.

8. A receiver, comprising:

a receive circuit configured to receive a second sequence which is generated based on a first sequence c(i), where i=0, 1, . . . , M_max−

1, and M_max is a length of the first sequence c(i); and

a data processor configured to process the second sequence,

wherein the first sequence c(i) is defined by a first m-sequence x(i) and a second m-sequence y(i) as shown;

c(i)=(x(i+Nc)+y(i+Nc))mod 2

x(i+31)=(x(i+3)+x(i))mod 2

y(i+31)=(y(i+3)+y(i+2)+y(i+1)+y(i))mod 2

where Nc is a constant, and

wherein the first sequence c(i) is initialized with an initial value obtained on the basis of (2N_ID^cell+1), where N_ID^cell is a cell identifier.

9. The receiver of claim 8, wherein the first m-sequence x(i) is initialized with x(i)=1 at i=0, x(i)=0 at i=1, 2, . . . , 30, and the second m-sequence y(i) is initialized with the initial value.