Turbo Receiver for DS-SS Systems Employing Parity Bit Selected Spreading Codes

In this paper a turbo receiver for direct sequence spread spectrum (DS-SS) systems employing parity bit selected spreading code (SS-PB) is proposed where detection and decoding are performed iteratively for each detected bit in the receiver. In SS-PB systems, parity bits generated by a linear block encoder are used to select a spreading code from a set of orthogonal spreading sequences. Performance evaluation in both additive white Gaussian noise (AWGN) and fading channels show a significant reduction in bit error rates (BER) when a turbo receiver is used in these systems.