Details of Research Outputs

IEEE 802.16 PMP mode recommends using truncated Binary Exponential Backoff (BEB) algorithm to resolve the contention when multiple Subscriber Stations (SSs) compete for the connection and resource allocation from the Base Station (BS). The BEB approach may not be effective and transmission opportunities (TOs) may be wasted due to independent contention and backoff of each SS. This paper proposes an efficient coordinated backoff algorithm (COB) through BS coordination so that a global window can be assigned by the BS and the TOs can be effectively consumed by the SSs. Theoretical analysis and simulation results show that COB is adaptive to the dynamic change of active SSs and outperforms the BEB approach. © Springer-Verlag Berlin Heidelberg 2006.