Evaluation of BER Performance of Up- and Downlink Code Spread CDMA systems

نویسندگان

  • Anders Persson
  • Johan Lassing
  • Tony Ottosson
  • Erik Ström
چکیده

The bit error rate (BER) of a code spread CDMA system, using low rate convolutional codes for spreading, is analyzed. The system is assumed to operate over a Rayleigh flat fading channel, and white Gaussian noise is added at the receiver front-end. Based on a Gaussian approximation, expressions for the pdf of the signal-to-noise ratios are derived for both upand downlink transmission. Computer simulations of the system BER, as well as analytical results based on a union bound, are presented. The analytical results are in close agreement with the computer simulations.

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تاریخ انتشار 2007