Multistage Selective ML Decoding for Multidimensional Multicode DS-CDMA with Precoding

A high-rate, reliable uplink transmission is designed using multistage selective maximum-likelihood (ML) decoding for the multicode (MC) direct-sequence code-division multiple access (DS-CDMA) with precoding. The precoding achieves a constant envelope MC signal by adding some redundancy bits, resulting in rate loss, but multidimensional signaling on top of MC DS-CDMA enables to further increase the date rate. The designed multistage selective ML decoding is shown to be promising for use in uplink high-rate and reliable data transmission.