On the performance of biorthogonal pulse position modulated direct-sequence CDMA communication

We propose a code-division multiple-access (CDMA) scheme based on biorthogonal pulse position modulated direct sequence. Unlike classical CDMA using bit-by-bit spreading, this scheme utilizes symbol-by-symbol spreading which effectively reduces the multiple-access interference. Compared to the orthogonal CDMA using symbol-by-symbol spreading, the proposed biorthogonal CDMA minimizes the receiver complexity while it causes a negligible performance degradation. Its simple receiver structure will be suitable for use in CDMA wireless local communications. The biorthogonal CDMA proposed here shows great promise for practical implementation both from the performance and complexity points of view