On the performance of a higher order alphabet size in CDMA
L.B. Milstein, Myoung-Seob Lim · IEEE Communications Letters · 1997
Due to the desire for the next generation of wireless communications systems to be able to support higher data rate, multimedia, traffic, it is of interest to determine if the use of a higher order alphabet size, in conjunction with code division multiple access (CDMA) signaling, will allow enhanced performance. We compare the performance of an asynchronous CDMA system when a 16-QAM alphabet is used with that of a CDMA system employing QPSK as the modulation format.