Uplink synchronous WCDMA combined with variable modulation and coding

Previous studies show a high potential capacity gain for uplink synchronous WCDMA systems in low dispersive environments when users in the same cell are separated by orthogonal codes. However, the number of available orthogonal codes tends to limit the capacity gain of this scheme. In this paper, variable modulation and coding is introduced as a solution to improve the channelization code utilization per user equipment and thereby increase the capacity of uplink synchronous WCDMA. The radio resource management algorithms to support this scheme are presented. Theoretical and simulation results on the capacity gain of uplink synchronous WCDMA combined with variable modulation and coding are presented. A 29% capacity gain is obtained for a pedestrian micro-cell environment.