Congestion control schemes for reverse link data transmission in multimedia CDMA systems

We investigate the congestion control schemes for reverse link in code division multiple access multimedia systems. We propose four schemes according to the control bit setting methods at base and the rate decision schemes in mobiles. With the proposed schemes, all mobiles control their transmission power and rate simultaneously. As the aggregate effect, the cell-wide congestion control is accomplished. The performance of systems with the proposed schemes are evaluated using computer simulation and compared with each other. Under a congested situation, the proposed schemes guarantee the priority of real-time traffic over non-real-time traffic and prevent an excessively high error rate for real-time services. We describe and evaluate the proposed schemes under the system model assumption based on 1xEV-DO and cdma2000. However, the proposed schemes can be also applied to wide-band code division multiple access systems with minor modification.