Cross-Layer Design Based Code Family Extension for CC/DS-CDMA Systems

A complete complementary codes based direct sequence code division multiple access (CC/DS-CDMA) system was recently proposed to offer isotropic interference free transmissions. Instead of being restricted by interference, the capacity of CC/DS-CDMA, however, is constrained by the number of code flocks due to the small family size of current CC codes. In this article, an channel-dependent code family extension (COFE) scheme is proposed to increase the system capacity. The performance of the COFE scheme is investigated through extensive computer simulations. It is concluded that the COFE scheme not only tends to hold the interference-free property of CC/DS-CDMA, but also offers significant spectrum efficiency and system capability in terms of supporting applications with diverse QoS requirements.