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Applications of Walsh Functions and the FHT in CDMA Technology

  • Ephraim Zehavi
Part of the Information Technology: Transmission, Processing and Storage book series (PSTE)

Abstract

A unified approach for modulation and demodulation of CDMA signaling based on IS-95 standard [1] is proposed. We propose a simpler forward link design, based on Fast Hadamard Transform (FHT) for generating the composite signal. In some systems, available power is a scarce resource and some power saving can be obtained when the user terminal is able to derive its phase, time and frequency references without the aid of a pilot signal. This necessitates some form of suppressed carrier tracking. A modified receiver using the FHT technique is proposed to implement phase, frequency and time tracking at the user terminal.

Keywords

Hadamard Matrix Frame Error Rate Phase Ambiguity User Terminal Pilot Signal 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer-Verlag London Limited 1996

Authors and Affiliations

  • Ephraim Zehavi
    • 1
  1. 1.Qualcomm Inc.San DiegoUSA

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