SEQUENCE GENERATING METHOD FOR EFFICIENT DETECTION AND METHOD FOR TRANSMITTING AND RECEIVING SIGNALS USING THE SAME

• US 20140029602A1
• Filed: 07/23/2013
• Published: 01/30/2014
• Est. Priority Date: 12/19/2006
• Status: Active Grant

• Current Assignee: Vivo Mobile Communication Co., Ltd. (Vivo Communication Technology Co. Ltd.)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: HAN, Seung Hee, NOH, Min Seok, KWON, Yeong Hyeon, LEE, Hyun Woo, KIM, Dong Cheol, KWAK, Jin Sam
• Granted Patent: US 8,948,294 B2
• Time in Patent Office: Days
• US Class Current: 370/350
• CPC Class Codes: H04J 11/0073 Acquisition of primary synchronisation channel, e.g. detection of cell-ID within cell-ID group
• CPC Class Codes: H04J 13/0062 Zadoff-Chu
• CPC Class Codes: H04J 2011/0096 Network synchronisation
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 25/0228 with direct estimation from sounding signals
• CPC Class Codes: H04L 27/2605 Symbol extensions, e.g. Zero Tail, Unique Word [UW]
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/26132 using repetition
• CPC Class Codes: H04L 27/2614 Peak power aspects
• CPC Class Codes: H04L 27/2615 Reduction thereof using coding
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 27/2657 Carrier synchronisation
• 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 5/0066 Requirements on out-of-channel emissions
• CPC Class Codes: H04L 7/0087 Preprocessing of received signal for synchronisation, e.g. by code conversion, pulse generation or edge detection
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others

Abstract

A sequence generation method for allowing a reception end to effectively detect a sequence used for a specific channel of an OFDM communication system, and a signal transmission/reception method using the same are disclosed. During the sequence generation, an index is selected from among the index set having the conjugate symmetry property between indexes, and a specific part corresponding to the frequency “0” is omitted from a transmitted signal. In addition, a reception end can calculate a cross-correlation value between a received (Rx) signal and each sequence using only one cross-correlation calculation based on the conjugate symmetry property.

Claims

1. A method for transmitting synchronization signals from a base station, the method comprising:

acquiring a primary synchronization signal generated using a Constant Amplitude Zero Auto-Correlation (CAZAC) sequence having a root index M and having a length L;

acquiring a secondary synchronization signal informing a cell group ID;

transmitting the primary synchronization signal at a last symbol of a specific time domain unit to one or more terminals; and

transmitting the secondary synchronization signal at a second-to-last symbol of the specific time domain unit to the one or more terminals,

wherein the root index M is one among a root index set comprising m₀ and m₁ meeting

m₀+m₁=(½

*L)*n

or

m₀−

m₁=±

(½

*L)*n, and

wherein n is an integer greater than 0.

2. The method of claim 1, wherein the primary synchronization signal is for time and frequency synchronization.

3. The method of claim 1, wherein the primary synchronization signal is distinguished from other primary synchronization signal based on a correlation operation.

4. A method for receiving synchronization signals at a terminal, the method comprising:

receiving a primary synchronization signal at a last symbol of a specific time domain unit from a base station; and

receiving a secondary synchronization signal informing a cell group ID at a second-to-last symbol of the specific time domain unit from the base station,

wherein the primary synchronization signal is generated using a Constant Amplitude Zero Auto-Correlation (CAZAC) sequence having a root index M and having a length L,

wherein the root index M is one among a root index set comprising m₀ and m₁ meeting

m₀+m₁=(½

*L)*n

or

m₀−

m₁=±

(½

*L)*n, and

wherein n is an integer greater than 0.

5. The method of claim 4, wherein the primary synchronization signal is for time and frequency synchronization.

6. The method of claim 4, wherein the primary synchronization signal is distinguished from other primary synchronization signal based on a correlation operation.

7. A base station for transmitting synchronization signals, the base station comprising:

a processor for acquiring a primary synchronization signal generated using a Constant Amplitude Zero Auto-Correlation (CAZAC) sequence having a root index M and having a length L, and a secondary synchronization signal informing a cell group ID,

a transmitter for transmitting the primary synchronization signal at a last symbol of a specific time domain unit, and the secondary synchronization signal at a second-to-last symbol of the specific time domain unit, to the one or more terminals,

wherein the root index M is one among a root index set comprising m₀ and m₁ meeting

m₀+m₁=(½

*L)*n

or

m₀−

m₁=±

(½

*L)*n, and

wherein n is an integer greater than 0.

8. The base station of claim 7, wherein the primary synchronization signal is for time and frequency synchronization.

9. The base station of claim 7, wherein the primary synchronization signal is distinguished from other primary synchronization signal based on a correlation operation.

10. A terminal for receiving synchronization signals, the terminal comprising:

a receiver for receiving a primary synchronization signal at a last symbol of a specific time domain unit, and a secondary synchronization signal informing a cell group ID at a second-to-last symbol of the specific time domain unit from the base station,

wherein the primary synchronization signal is generated using a Constant Amplitude Zero Auto-Correlation (CAZAC) sequence having a root index M and having a length L,

wherein the root index M is one among a root index set comprising m₀ and m₁ meeting

m₀+m₁=(½

*L)*n

or

m₀−

m₁=±

(½

*L)*n, and

wherein n is an integer greater than 0.

11. The terminal of claim 10, wherein the primary synchronization signal is for time and frequency synchronization.

12. The terminal of claim 10, wherein the primary synchronization signal is distinguished from other primary synchronization signal based on a correlation operation.