Synchronization signal used to identify code groups

• US 20040085920A1
• Filed: 10/28/2003
• Published: 05/06/2004
• Est. Priority Date: 05/22/2000
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Ozluturk, Fatih M., Sezgin, Nadir
• Granted Patent: US 7,102,994 B2
• Time in Patent Office: Days
• US Class Current: 370/320
• CPC Class Codes: H04B 1/70735 Code identification H04B1/7083 takes precedence
• CPC Class Codes: H04B 1/70752 Partial correlation
• CPC Class Codes: H04B 1/7083 Cell search, e.g. using a three-step approach
• CPC Class Codes: H04B 1/7093 Matched filter type
• CPC Class Codes: H04B 2201/70701 featuring pilot assisted reception
• CPC Class Codes: H04B 2201/70702 Intercell-related aspects
• CPC Class Codes: H04L 27/2053 using more than one carrier, e.g. carriers with different phases
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A synchronization signal is used in a wireless time division duplex communication system. The time division duplex communication system uses time slots in repeating frames for communication. The synchronization signal is transmitted from a base station to identify a code group associated with the base station. The synchronization signal comprises a spreading code associated with a selected base station. Binary bits identifying a code group associated with the selected base station are modulated by said spreading code using binary phase shift keying.

Claims

1. A synchronization signal for use in a wireless time division duplex communication system, the time division duplex communication system using time slots in repeating frames for communication, the synchronization signal is transmitted from a base station to identify a code group associated with the base station, the synchronization signal comprising:

a spreading code associated with a selected base station; and

binary bits identifying a code group associated with the selected base station modulated by said spreading code using binary phase shift keying.

2. The synchronization signal of claim 1 wherein the binary bits are produced by combining a binary code group identifier with a selected row of a Hadamarak matrix.

3. The synchronization signal of claim 2 wherein the selected row is from a set of possibly selected rows of Hadamarak matrix;

the possibly selected rows comprising rows 24, 40, 56, 104, 120 and 136.

4. The synchronization signal of claim 1 wherein the signal is transmitted at a predetermined time offset from a time slot leading boundary.

5. The synchronization signal of claim 1 wherein the base station also transmits another signal, both the another signal and the synchronization signal are spread with the spreading code.

6. The synchronization signal of claim 5 wherein both the another signal and the synchronization signal are transmitted at a same predetermined time offset from a time slot leading boundary.

7. The synchronization signal of claim 1 wherein the synchronization signal is selectively transmitted using an in-phase or quadrature phase carrier.