An efficient detection technique for synchronous CDMA communication systems based on the expectation maximization algorithm

Maximum likelihood detection of superimposed signals in code-division multiple access (CDMA) communication systems has a computational complexity that is exponential in the number of users, and its implementation is practically prohibitive even for a moderate number of users. Applying the expectation maximization algorithm to this problem, we decompose the multiuser detection problem into a series of single-user problems, and thus present an iterative computationally efficient algorithm for detection of superimposed signals in synchronous direct-sequence CDMA communication systems. The resulting structure includes the well-known multistage detector as one of its special cases. With a proper choice of its parameters, the new detector can achieve the advantages of both the multistage and conventional detector and have good performance for both strong and weak users.

[1]  Fu-Chun Zheng,et al.  Near-far resistant detection of CDMA signals via isolation bit insertion , 1995, IEEE Trans. Commun..

[2]  J. P. McGeehan,et al.  A near-far resistant sliding window decorrelating algorithm for multi-user detectors in DS-CDMA systems , 1992, [Conference Record] GLOBECOM '92 - Communications for Global Users: IEEE.

[3]  Sergio Verdú,et al.  Near-far resistance of multiuser detectors in asynchronous channels , 1990, IEEE Trans. Commun..

[4]  J. M. Holtzman,et al.  DS/CDMA successive interference cancellation , 1994, Proceedings of IEEE 3rd International Symposium on Spread Spectrum Techniques and Applications (ISSSTA'94).

[5]  H. Vincent Poor.  On parameter estimation in DS/SSMA formats , 1989 .

[6]  Mahesh K. Varanasi,et al.  Near-optimum detection in synchronous code-division multiple-access systems , 1991, IEEE Trans. Commun..

[7]  Ehud Weinstein,et al.  Parameter estimation of superimposed signals using the EM algorithm , 1988, IEEE Trans. Acoust. Speech Signal Process..

[8]  Masoumeh Nasiri-Kenari,et al.  An efficient soft-in-soft-out multiuser detector for synchronous CDMA with error-control coding , 1998 .

[9]  M. Nasiri-Kenari,et al.  An efficient decoding technique for CDMA communication systems based on the expectation maximization algorithm , 1996, Proceedings of ISSSTA'95 International Symposium on Spread Spectrum Techniques and Applications.

[10]  Upamanyu Madhow,et al.  MMSE interference suppression for direct-sequence spread-spectrum CDMA , 1994, IEEE Trans. Commun..

[11]  Craig K. Rushforth,et al.  A Family of Suboptimum Detectors for Coherent Multiuser Communications , 1990, IEEE J. Sel. Areas Commun..

[12]  Andrew J. Viterbi,et al.  Very Low Rate Convolutional Codes for Maximum Theoretical Performance of Spread-Spectrum Multiple-Access Channels , 1990, IEEE J. Sel. Areas Commun..

[13]  Masao Nakagawa,et al.  Microcellular CDMA system with a linear multiuser interference canceler , 1994, IEEE J. Sel. Areas Commun..

[14]  Sergio Verdú,et al.  Linear multiuser detectors for synchronous code-division multiple-access channels , 1989, IEEE Trans. Inf. Theory.

[15]  Alexandra Duel-Hallen,et al.  Decorrelating decision-feedback multiuser detector for synchronous code-division multiple-access channel , 1993, IEEE Trans. Commun..