Link performance of time-division duplex DS-CDMA mobile communication system

We present the link performance of a wideband time-division duplex DS-CDMA system for the third-generation mobile communication system. Computer simulations by means of Monte Carlo integration are made to evaluate the link performance of the time-division duplex DS-CDMA system under a generalized Rayleigh fading multipath channel. 8 kbit/s speech service is mainly adopted. The differences from frequency-division duplexing (FDD) are also shown, and the advantages of using a TDD system are discussed. Simulation results under various radio channel environments are given and the impact of Doppler shift on the link performance is investigated. Some techniques that can be used to reduce the required E/sub b//N/sub 0/ are also employed.