Multiple-access interference reduction for QS-CDMA systems with a novel class of polyphase sequences

In this paper, a new class of polyphase sequences for CDMA systems and its generation method are suggested, and the correlation properties of the sequence are investigated. The performance of the sequence in quasi-synchronous CDMA (QS-CDMA) systems is investigated under a frequency-selective, time-nonselective, slow Nakagami fading channel with additive white Gaussian noise (AWGN). It is shown that the performance of the QS-CDMA systems using the suggested sequence is independent of the number of users and is much better than that using the PN sequence.

[1]  Ronald A. Iltis,et al.  Multiuser detection of quasisynchronous CDMA signals using linear decorrelators , 1996, IEEE Trans. Commun..

[2]  Naoki Suehiro,et al.  A signal design without co-channel interference for approximately synchronized CDMA systems , 1994, IEEE J. Sel. Areas Commun..

[3]  Naoki Suehiro,et al.  N-shift cross-orthogonal sequences , 1988, IEEE Trans. Inf. Theory.

[4]  Laurence B. Milstein,et al.  Rejection of Narrow-Band Interference in PN Spread-Spectrum Systems Using Transversal Filters , 1982, IEEE Trans. Commun..

[5]  Sergio Verdu,et al.  Multiuser Detection , 1998 .

[6]  Naoki Suehiro,et al.  Modulatable orthogonal sequences and their application to SSMA systems , 1988, IEEE Trans. Inf. Theory.

[7]  John G. Proakis,et al.  Digital Communications , 1983 .

[8]  Michael B. Pursley.  Spread-Spectrum Multiple-Access Communications , 1981 .

[9]  Seokho Yoon,et al.  On the generation and analysis of a modulated orthogonal sequence , 2000, Signal Process..

[10]  Iickho Song,et al.  Design and analysis of concatenated coded DS/CDMA systems in asynchronous channels , 1999 .

[11]  Ronald A. Iltis.  Demodulation and code acquisition using decorrelator detectors for QS-CDMA , 1996, IEEE Trans. Commun..

[12]  Sergio Verdú,et al.  Minimum probability of error for asynchronous Gaussian multiple-access channels , 1986, IEEE Trans. Inf. Theory.

[13]  Laurence B. Milstein,et al.  Coherent DS-CDMA performance in Nakagami multipath fading , 1995, IEEE Trans. Commun..

[14]  P. Vijay Kumar,et al.  4-phase Sequences with Near-optimum Correlation Properties , 1992, IEEE Trans. Inf. Theory.

[15]  Kyung Hi Chang,et al.  Optimal PN sequence design for quasisynchronous CDMA communication systems , 1997, IEEE Trans. Commun..

[16]  N. Suehiro.  Binary or quadriphase signal design for approximately synchronized CDMA systems without detection sidelobe nor co-channel interference , 1996, Proceedings of ISSSTA'95 International Symposium on Spread Spectrum Techniques and Applications.

[17]  F. Hsu,et al.  Digital Whitening Techniques for Improving Spread Spectrum Communications Performance in the Presence of Narrowband Jamming and Interference , 1978, IEEE Trans. Commun..

[18]  M.B. Pursley,et al.  Crosscorrelation properties of pseudorandom and related sequences , 1980, Proceedings of the IEEE.

[19]  Iickho Song,et al.  Analysis of quasi-ML multiuser detection of DS/CDMA systems in asynchronous channels , 1999, IEEE Trans. Commun..