Pulse or digital communications – Systems using alternating or pulsating current – Plural channels for transmission of a single pulse train
Reexamination Certificate
2007-09-11
2011-12-20
Bocure, Tesfaldet (Department: 2611)
Pulse or digital communications
Systems using alternating or pulsating current
Plural channels for transmission of a single pulse train
C375S295000, C375S316000
Reexamination Certificate
active
08081695
ABSTRACT:
A system and method are provided for supplying a frequency-smoothed communications training signal. The method generates a frequency-smoothed unbiased training signal in a quadrature modulation transmitter. The frequency-smoothed unbiased training signal includes a plurality of pilot signal products, where each pilot signal product includes complex plane information represented by a reference frequency subcarrier, multiplying complex plane information represented by mirror frequency subcarrier. The sum of the plurality of pilot signal products is equal to zero. The method supplies the frequency-smoothed unbiased training signal so that it may be transmitted within a single symbol period. System and methods are also provided for using a frequency-smoothed training signal in the calculation of a receiver channel estimate.
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Chrabieh Rabih
Soliman Samir S.
Bocure Tesfaldet
QUALCOMM Incorporated
Qualcomm Patent Group
Williams Lawrence
Yancey, Jr. James H.
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