Method of generating an index value

• US 7,746,920 B2
• Filed: 10/06/2008
• Issued: 06/29/2010
• Est. Priority Date: 02/27/2001
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Grieco, Donald M, Demir, Alpaslan
• Primary Examiner(s): Tran; Khai
• Application Number:
  US12/245,800
• Publication Number:
  US 20090034670A1
• Time in Patent Office: 631 Days
• Field of Search: 375/354, 375/347, 375/349, 375/342, 375/130, 375/147, 375/148, 375/267, 375/150, 370/342, 370/335, 370/331, 455/436, 455/437, 455/429
• US Class Current: 375/150
• CPC Class Codes: H04B 1/7083 Cell search, e.g. using a three-step approach
• CPC Class Codes: H04J 11/0069 Cell search, i.e. determining cell identity [cell-ID] design of multiplexing codes H04J13/00; processing access restriction or access information H04W48/16; discovery of network devices for network data management H04W8/005; sounding signals for channel estimation H04L25/0226; structure of reference signals in multicarrier modulation systems H04L27/2613; frame, time or carrier synchronisation in multicarrier modulation systems H04L27/2655
• CPC Class Codes: H04J 3/0608 Detectors therefor, e.g. correlators, state machines
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 56/00 Synchronisation arrangements

Abstract

A method of generating an index value associated with a primary synchronization code within a communication signal includes splitting a sampled communication signal into even and odd samples. The even and odd samples are correlated with a primary synchronization code of the communication signal and complex values of the even and odd samples are generated. Signal strength values for the even and odd samples are approximated and the approximate signal strength values within a frame of the communication signal are accumulated. A highest accumulated signal strength value is assigned as an index value.

Claims

1. A method of generating an index value associated with the primary synchronization code within a communication signal, comprising:

splitting a sampled communication signal into even and odd samples using a splitter;

correlating the even and odd samples with the primary synchronization code of the communication signal using a Hierarchical Golay Correlator (HGC);

generating complex values of the even and odd samples using the HGC;

approximating signal strength values for the complex values of the even and odd samples using an Absolute Value Modifier (AVM);

accumulating the approximate signal strength values within a frame of the communication signal using an accumulator; and

assigning the index value to a highest accumulated signal strength value using a decision circuit.

2. The method of claim 1, further comprising:

assigning a chip offset to the index value based on the index value.

3. The method of claim 1, further comprising:

generating the index value associated with the primary synchronization code.

4. An apparatus for generating a index value associated with a primary synchronization code within a communication signal, comprising:

a splitter configured to split a sampled communication signal into even and odd samples;

a Hierarchical Golay Correlator (HGC) configured to correlate the even and odd samples with the primary synchronization code of the communication signal and configured to generate complex values of the even and odd samples;

an Absolute Value Modifier (AVM) configured to approximate signal strength values for the complex values of the even and odd samples;

an accumulator configured to accumulate the approximate signal strength values within a frame of the communication signal; and

a decision circuit configured to assign the index value to a highest accumulated signal strength value.