Title :
A noise-whitening approach to multiple access noise rejection .I. Theory and background
Author :
Monk, Anton M. ; Davis, Mark ; Milstein, Laurence B. ; Helstrom, Carl W.
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., San Diego, La Jolla, CA, USA
fDate :
6/1/1994 12:00:00 AM
Abstract :
Minimum probability of bit error is difficult to achieve in a DS-CDMA receiver. Since multiple-access noise is the sum of many independent random processes, it is reasonable to approximate it by a Gaussian process of the same power spectral density. This leads to the criterion of maximizing signal-to-noise ratio (SNR). In this paper, receivers that maximize SNR in a particular DS-CDMA system model under various constraints are proposed and analyzed. The method proposed here does not require locking and despreading multiple arriving CDMA signals. The maximization of SNR is compared with the minimization of probability of error, when the receiver is constrained to operate bit-by-bit, in the absence of knowledge of the other users´ spreading codes, timing, and phase
Keywords :
code division multiple access; error statistics; filtering and prediction theory; interference suppression; probability; radio receivers; radiofrequency interference; random processes; signal processing; spread spectrum communication; stochastic processes; CDMA signals; DS-CDMA receiver; DS-CDMA system model; Gaussian process; SNR maximization; bit error probability minimization; independent random processes; multiple access noise rejection; multiple-access noise; noise-whitening; power spectral density; signal-to-noise ratio; AWGN; Additive white noise; Background noise; Colored noise; Gaussian noise; Multiaccess communication; Nonlinear filters; Probability; Signal to noise ratio; Timing;
Journal_Title :
Selected Areas in Communications, IEEE Journal on
