Contention Window Adaptive Adjustment Strategy for Fairness in Multi-rate IEEE 802.11 Network

The wireless network technology represented by IEEE 802.11 technology plays an increasingly important role in practice. However, in the multi-node and multi-rate network scenario, this technology will produce abnormal performance, resulting in high-speed and medium-speed nodes. The throughput drops to the same as the throughput of the low-speed node, which reduces the total throughput of the system and degrades the performance. Aiming at this problem, a solution (TRCWAA) is designed. Through the minimum contention window, the size of the minimum contention window of each node is inversely proportional to its transmission rate, so as to realize the reasonable allocation of channel resources. Theoretical analysis and simulation experiments show that the TRCWAA strategy can well solve the problem of abnormal performance and unfairness, greatly improve the network fairness, and improve the total throughput of the system. In addition, the significant advantage of this method is that it only needs to make minor modifications on the basis of 802.11, that is, to adjust the minimum contention window size according to the transmission rate. Its physical implementation is very simple and convenient. No modification to the hardware, so it is easy to implement and generalize in real networks.