Applications of Walsh Functions and the FHT in CDMA Technology

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


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.


Hadamard Matrix Frame Error Rate Phase Ambiguity User Terminal Pilot Signal 
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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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