InterDigital Inc (IDCC)

[Gamco]

United States Patent 7,502,426
Li , et al. March 10, 2009

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Method for estimating signal magnitude, noise power, and signal-to-noise ratio of received signals


Abstract
An improved system and method for estimating one or more parameters, such as amplitude and signal-to-noise ratio, of a received signal, such as an M-QAM or q-ASK signal, is set forth herein. The amplitude of an M-QAM signal is estimated based upon known or ascertainable phase information regarding a plurality of transmitted symbols. The amplitude of a q-ASK signal is estimated based upon known or ascertainable magnitude information regarding a plurality of transmitted symbols. In another embodiment, the amplitude of an M-QAM or q-ASK signal is estimated based on statistical knowledge of the amplitude of the transmitted symbols. Other embodiments of the present invention estimate amplitude, noise power, and signal-to-noise ratio of a received signal utilizing second-order and fourth-order moments of received samples, a maximum likelihood searching process, or a Kurtosis estimation process.


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Inventors: Li; Bin (Ronkonkoma, NY), Sternberg; Gregory S. (Great Neck, NY), Pietraski; Philip J. (Huntington Station, NY)
Assignee: InterDigital Technology Corporation (Wilmington, DE)

Appl. No.: 10/750,203
Filed: December 31, 2003

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Related U.S. Patent Documents

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Application Number Filing Date Patent Number Issue Date
60501302 Sep., 2003


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Current U.S. Class: 375/320
Current International Class: H03D 1/24 (20060101)
Field of Search: 375/261,298,316,320 329/304,347,348,349 332/103,120,149,150 370/207