Title :
A noise-whitening approach to multiple-access noise rejection in a CDMA system
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
Abstract :
Multiple-access interference is a limiting factor in DS-CDMA. 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 performance of the system is analyzed 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; interference suppression; radio receivers; radiofrequency interference; random processes; spread spectrum communication; stochastic processes; CDMA system; DS-CDMA; Gaussian process; SNR; bit-by-bit operation; multiple-access interference; multiple-access noise rejection; noise whitening; power spectral density; random processes; receiver; signal-to-noise ratio; Colored noise; Gaussian noise; Multiaccess communication; Multiple access interference; Nonlinear filters; Power engineering and energy; Power engineering computing; Probability; Signal to noise ratio; Transmitters;
Conference_Titel :
Telesystems Conference, 1994. Conference Proceedings., 1994 IEEE National
Conference_Location :
San Diego, CA
Print_ISBN :
0-7803-1869-2
DOI :
10.1109/NTC.1994.316660
