InterDigital Inc (IDCC)

[Gamco]

United States Patent 8,023,399
Pan , et al. September 20, 2011

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Channel estimation in a wireless communication system


Abstract
A plurality of communication bursts are transmitted substantially simultaneously in a time slot of a time division duplex/code division multiple access communication system. The communication system has a maximum number of K midamble shifts. Each burst has an assigned midamble. Each midamble is a shifted version of a basic midamble code having a period of P. A combined signal is received. The combined signal includes a received version of each of the communication burst's midambles. A P by P square circulant matrix is constructed including the K midamble shifts. A channel response is determined for each of the K midamble shifts using a prime factor algorithm (PFA) discrete Fourier transform (DFT) algorithm, the received combined signal and the P by P square circulant matrix. The PFA DFT algorithm has a plurality of stages. Each stage has P inputs.


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Inventors: Pan; Jung-Lin (Selden, NY), Kim; Younglok (Seoul, KR), Zeira; Ariela (Huntingdon, NY)
Assignee: InterDigital Technology Corporation (Wilmington, DE)

Appl. No.: 11/894,282
Filed: August 20, 2007

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Related U.S. Patent Documents

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Application Number Filing Date Patent Number Issue Date
10308473 Dec., 2002 7260056
60384194 May., 2002


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Current U.S. Class: 370/210 ; 370/280; 370/335; 370/342; 375/131; 375/147; 375/346
Current International Class: H04J 11/00 (20060101); H03D 1/04 (20060101); H04B 1/69 (20110101); H04B 7/216 (20060101)
Field of Search: 370/210,280,335,342 375/131,147,346

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