Robust CDMA radio transmission over fading channels

This paper is concerned with the design and performance evaluation of a direct-sequence, spread-spectrum transmission and signal detection technique for application to code division multiple access mobile radio networks. Unlike conventional differential encoding/detection of data symbols, such a technique envisages differential encoding/detection of the spreading code chips to counteract the fast time-selective fading encountered in mobile radio transmissions. Binary PSK modulation on a Ricean frequency-flat fading channel is assumed, with Gaussian and Rayleigh channels as particular cases. The bit error rare performance of the receiver is analytically evaluated as a function of the relevant system parameters.