Performance Evaluation of CDMA Systems Based on User Location

In order to support high data-rate service in an integrated CDMA system, it is required to allocate resources for data users with high spectral efficiency. In this paper, we analyze the performance of two resource allocation schemes such as a simultaneous resource allocation(SRA) scheme and a throughput maximization(TM) scheme. In the throughput maximization scheme, the throughput of data users can be maximized when one among data users is allowed to transmit information at any given time. To apply this scheme to an voice/data CDMA system, resources are first allocated to voice users and then residual resources are allocated to data users based on the throughput maximization strategy. For more practical approach, the transmission power of mobile stations is assumed to be limited. Due to this assumption, the performance of two resource allocation schemes is varied according to the location of mobile stations. We also show the performance under perfect power control and imperfect power control. In order to verify the analysis results, we perform the simulation under the same environment. Simulation and analysis results show that the TM scheme has higher throughput than the SRA scheme under the conditions that the mobile is located in a limited boundary and the variation of E_b/N_o is minimized.