Performance analysis of DS-CDMA system with space-time multiuser detection using a class of chaotic spreading sequences

Abstract

Chaotic spreading sequences are used in spread spectrum communication systems due to their potential advantage over the conventional pseudo-noise sequences in terms of security and synchronization. This paper uses a class of chaotic binary sequences as the spreading waveforms in a direct sequence code division multiple access system. The loss of orthogonality between spreading waveforms in fading multipath channels is mitigated by employing multiuser detection with multiple transmit and receive antennas. The performance of the system with space time multiuser detection is analyzed in fading multipath channels with additive white Gaussian noise. The simulation results show that the DS-CDMA system with chaotic sequence having prescribed statistical properties can accommodate more users for a fixed length of spreading sequence.