Optimum asymptotic multiuser efficiency of randomly spread CDMA

@article{Tse2000OptimumAM,
  title={Optimum asymptotic multiuser efficiency of randomly spread CDMA},
  author={David Tse and Sergio Verd{\'u}},
  journal={IEEE Trans. Inf. Theory},
  year={2000},
  volume={46},
  pages={2718-2722}
}
This correspondence analyzes the high signal-to-noise ratio (SNR) performance of optimum multiuser detectors for synchronous direct-sequence spread spectrum with random spreading in an additive white Gaussian noise channel. Under very general conditions on the received powers, we show that the optimum asymptotic efficiency of a K-user system with spreading gain N converges to 1 almost surely as K/spl rarr//spl infin/, and K/N is kept equal to an arbitrary nonzero constant. Therefore, the… 

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