leveraging spatial reuse with adaptive carrier sensing in 802.11 wireless networks
Recent studies indicate that by improving the spatial reuse ratio the throughput of 802.11 wireless networks can be improved. In this paper, we study the impact of physical carrier sensing and channel rate on the throughput of 802.11 wireless networks with chain topology. Firstly, this paper proposes that by adopting different carrier sensing thresholds for the transmissions of RTS and CTS, the blocking problem caused by exposed terminals is alleviated significantly. In 802.11 wireless networks with this modification, the spatial reuse ratio under certain channel rates can be increased to 1/3, which is the highest value to our best knowledge. Secondly, in multirate networks, we demonstrate that 1/3 is still the best value of special reuse ratio in terms of maximizing the achievable data rate. Thirdly, this paper proposes a new way to address the intraflow contention by decreasing the carrier sensing threshold of the source node. This method has shorter response time than that of the traditional method with adjusting the backoff window size. Finally, extensive simulations are implemented in NS2. The results show that our scheme significantly improves the throughput of 802.11 wireless networks with chain topology.
spatial reuse carrier sensing medium access control (mac) interference