USER EQUIPMENT FOR SYNCHRONIZING TO A TDD BASE STATION

• US 20090268644A1
• Filed: 07/09/2009
• Published: 10/29/2009
• 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 8,130,730 B2
• Time in Patent Office: Days
• US Class Current: 370/280
• 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 time division duplex (TDD) user equipment (UE) is configured to synchronize to a TDD base station. The UE includes an antenna, a primary synchronization code matched filter, a first plurality of secondary synchronization code matched filters, a second plurality of secondary synchronization code matched filters, and a processor in communication with the first and second plurality of secondary synchronization code matched filters. The first plurality of secondary synchronization code matched filters determines secondary synchronization codes sent on a first carrier and the second plurality of secondary synchronization code matched filters determines secondary synchronization codes sent on a second carrier. The processor is configured to determine a code group assignment and selected timeslot based upon an analysis of the secondary synchronization codes sent on the first and second carriers.

Claims

1. A time division duplex (TDD) user equipment (UE) configured to synchronize to a TDD base station, the UE comprising:

an antenna configured to receive a signal from the TDD base station;

a primary synchronization code matched filter configured to determine a primary synchronization code from the received signal;

a first plurality of secondary synchronization code matched filters configured to determine a first plurality of secondary synchronization codes sent on a first carrier from the received signal, wherein the first plurality of secondary synchronization codes are quadrature phased shift keyed (QPSK) modulated and the first carrier is an in-phase (I) carrier;

a second plurality of secondary synchronization code matched filters configured to determine a second plurality of secondary synchronization codes sent on a second carrier from the received signal, wherein the second plurality of secondary synchronization codes are QPSK modulated and the second carrier is a quadrature (Q) carrier; and

a processor in communication with the primary synchronization code matched filter and plurality of secondary synchronization code matched filters, the processor configured to determine a code group assignment and selected timeslot based upon an analysis of the secondary synchronization codes sent on the first and second carriers.

2. The TDD user equipment of claim 1 wherein each of the first and second plurality of secondary synchronization codes correspond to a row of a Hadamard matrix.

3. The TDD user equipment of claim 1 wherein there are 32 code groups.

4. The TDD user equipment of claim 3 wherein the first plurality of secondary synchronization codes is assigned to a first group of codes out of the 32 code groups and the second plurality of secondary synchronization codes is assigned to a second group of codes out of the 32 code groups.

5. The TDD user equipment of claim 4 wherein the first plurality of secondary synchronization codes is assigned to a lower group and the second plurality of secondary synchronization codes is assigned to a higher group.