United States Patent 7,561,615
Pietraski , et al. July 14, 2009
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Method and apparatus for compensating for phase noise of symbols spread with a long spreading code
Abstract
A method and apparatus for compensating for phase noise of symbols spread with a long spreading code are disclosed. To compensate for the phase noise, a phase error estimate is generated from despread symbols with a short spreading code. A phase correcting phasor is applied to chip rate data before despreading the data with a long spreading code. A signal-to-interference ratio (SIR) on a common pilot channel (CPICH) may be calculated by spreading the data with a parent spreading code in an orthogonal variable spreading factor (OVSF) code tree and by combining symbols. Alternatively, a magnitude of the symbols may be used in estimating the SIR. The SIR of a channel using a short spreading code and an SIR of a channel using a long spreading code are measured. The SIR of the channel with the long spreading code may be compensated in accordance with a difference between degradation of the SIRs.
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Inventors: Pietraski; Philip J. (Huntington Station, NY), Beluri; Mihaela (Glen Cove, NY), Yang; Rui (Greenlawn, NY), Chincholi; Amith Vikram (West Babylon, NY), Kearney; Kenneth P. (Smithtown, NY)
Assignee: InterDigital Technology Corporation (Wilmington, DE)
Appl. No.: 11/301,198
Filed: December 12, 2005
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Related U.S. Patent Documents
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Application Number Filing Date Patent Number Issue Date
60665122 Mar., 2005
60663874 Mar., 2005
60662976 Mar., 2005
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Current U.S. Class: 375/148 ; 370/342
Current International Class: H04B 1/69 (20060101); H04B 7/216 (20060101)
Field of Search: 375/148,130,147,149,349,347 370/320,335,342 455/62,69,103
