RS-CTDMA: a novel concept of multiple access design

RS-CDMA (rotated spectrum code division multiple access) is designed to yield a novel multiple access concept termed RS-CTDMA (rotated spectrum code time division multiple access) for mobile radio systems. The concept exploits the principle of CTDMA (code time division multiple access) to combine the advantages of the good user separation of TDMA and the spread spectrum of CDMA. Moreover, the concept allows multicode transmission, and thus high spectrum efficiency. Owing to its having the inherent features of both CDMA and TDMA, RS-CTDMA preserves maximum commonality with other air interfaces, and thus has the potential to be compatible with UMTS.