Multirate 3rd generation CDMA systems

An implementation technique for a code division multiple access (CDMA) multirate radio interface is presented. It is based on low rate orthogonal convolutional (LOROC) coding. A connection between LOROC encoding and the multiuser equalization structures of B.R. Petersen (1992) is established, and it is shown that the combined scheme is a strong candidate for implementing third-generation digital cellular systems capable of supporting multimedia services. The LOROC encoding scheme is reviewed with emphasis on the multiple access interference (MAI) characterization of LOROC encoded multirate spread spectrum signals. The effect of interleaving is also addressed. A multiuser equalizer particularly suitable for a MAI rejecting mobile hand-portable has been put together with a LOROC decoder. The implementation aspects and advantages of this combination are addressed