Simplified Multiaccess Interference Reduction for MC-CDMA With Carrier Frequency Offsets

Multicarrier code-division multiple-access (MC-CDMA) system performance can severely be degraded by multiaccess interference (MAI) due to the carrier frequency offset (CFO). We argue that MAI can more easily be reduced by employing complex carrier interferometry (CI) codes. We consider the scenario with spread gain N, multipath length L, and N users, i.e., a fully loaded system. It is proved that, when CI codes are used, each user only needs to combat 2(L - 1) (rather than N - 1) interferers, even in the presence of CFO. It is shown that this property of MC-CDMA with CI codes in a CFO channel can be exploited to simplify three multiuser detectors, namely, parallel interference cancellation (PIC), maximum-likelihood, and decorrelating multiuser detectors. The bit-error probability (BEP) for MC-CDMA with binary phase-shift keying (BPSK) modulation and single-stage PIC and an upper bound for the minimum error probability are derived. Finally, simulation results are given to corroborate theoretical results.

[1]  Geoffrey Ye Li,et al.  Simplified channel estimation for OFDM systems with multiple transmit antennas , 2002, IEEE Trans. Wirel. Commun..

[2]  L. Litwin,et al.  Error control coding , 2001 .

[3]  William H. Tranter,et al.  Overloaded array processing with spatially reduced search joint detection , 2001, IEEE J. Sel. Areas Commun..

[4]  James S. Lehnert,et al.  Multiple-access interference suppression for MC-CDMA by frequency-domain oversampling , 2005, IEEE Transactions on Communications.

[5]  Loïc Brunel Multiuser detection techniques using maximum likelihood sphere decoding in multicarrier CDMA systems , 2004, IEEE Transactions on Wireless Communications.

[6]  J.A.C. Bingham,et al.  Multicarrier modulation for data transmission: an idea whose time has come , 1990, IEEE Communications Magazine.

[7]  A. Robert Calderbank,et al.  Minimal tail-biting trellises: The Golay code and more , 1999, IEEE Trans. Inf. Theory.

[8]  Robert M. Gray,et al.  On the asymptotic eigenvalue distribution of Toeplitz matrices , 1972, IEEE Trans. Inf. Theory.

[9]  Zoran Zvonar,et al.  Multiuser detection in single-path fading channels , 1994, IEEE Trans. Commun..

[10]  William H. Press,et al.  Numerical recipes , 1990 .

[11]  Behnaam Aazhang,et al.  Multistage detection in asynchronous code-division multiple-access communications , 1990, IEEE Trans. Commun..

[12]  Balasubramaniam Natarajan,et al.  Large set of CI spreading codes for high-capacity MC-CDMA , 2004, IEEE Transactions on Communications.

[13]  C.-C. Jay Kuo,et al.  SPCp1-03: Orthogonal Codes for MAI-Free MC-CDMA with Carrier Frequency Offsets (CFO) , 2006, IEEE Globecom 2006.

[14]  S. Moshavi,et al.  Multi-user detection for DS-CDMA communications , 1996, IEEE Commun. Mag..

[15]  J. E. Glynn,et al.  Numerical Recipes: The Art of Scientific Computing , 1989 .

[16]  Paul H. Moose,et al.  A technique for orthogonal frequency division multiplexing frequency offset correction , 1994, IEEE Trans. Commun..

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

[18]  D. Divsalar,et al.  CDMA with interference cancellation for multiprobe missions , 1995 .

[19]  B. Natarajan,et al.  Parallel interference cancellation techniques for synchronous carrier interferometry/MC-CDMA uplink [4G cellular systems] , 2004, IEEE 60th Vehicular Technology Conference, 2004. VTC2004-Fall. 2004.

[20]  W. C. Jakes,et al.  Microwave Mobile Communications , 1974 .

[21]  Georgios B. Giannakis,et al.  Group-orthogonal multicarrier CDMA , 2004, IEEE Transactions on Communications.

[22]  C.-C. Jay Kuo,et al.  MAI-Free MC-CDMA Systems Based on Hadamard–Walsh Codes , 2006, IEEE Transactions on Signal Processing.

[23]  Y. Danieli Guide , 2005 .

[24]  E-L. Kuan,et al.  Overview of Multicarrier CDMA , 2004 .