Link adaptive multi-rate coding verification system for CDMA mobile communications

Mobile communications link adaptation maximises the efficient use of radio resources. Multi-rate source and channel coding (MRC) is one of the proposed techniques for link adaptation in future mobile communication systems. A MRC system trades-off the source codec bit rate against channel codec bit rate according to the prevailing channel conditions. This paper presents a CDMA verification environment that allows a comprehensive test of the MRC performance. It shows that by maintaining a satisfactory level of speech quality over a range of channel conditions, MRC results in an increase in the system capacity.