Joint Rate-Adaptive and Backoff Waiting Admission Control for Differentiated Services in CDMA Cellular Network

Call admission control should support different types of traffic with different quality of services (QoS) attributes in next generation wireless network. In the paper, we propose a novel call admission control working in conjunction with rate adaptation and backoff waiting schemes to improve the system performance. The transmission rates for multimedia calls can be adjusted to accommodate more calls while satisfying the minimum signal-to-interference ration(SIR) and transmission rate requirement. Also, binary exponential backoff algorithm for backoff waiting is introduced for rejected call to increase access opportunity, which only admits new calls for deferring in the system. Simulation results have demonstrated that the proposed adaptive CAC scheme achieves better performance when applied to realistic traffic conditions found in wireless multimedia networks.