Effects of adaptable channelization in Wi-Fi networks

The enormous increase in wireless enabled devices has posed a great challenge for effective resource sharing in Wi-Fi networks. This challenge has triggered the re-evaluation of wireless resource sharing protocols. Available frequency spectrum is probably the most valuable network resource. Therefore, effective utilization of this scarce resource is highly desired. The traditional channelization of 802.11 networks, has proven inefficient in optimal use of frequency spectrum. In this work, we analyze the effect of using flexible channelization, on essential wireless performance parameters, like throughput, interference, range and power consumption. We propose a dynamic and flexible, channel assignment and spectrum sharing algorithm, that allocates channels with high granularity, thus maximizing the spectrum usage. The proposed algorithm is based on the throughput requirements and signal strength values of a specific node. Through rigorous experimentation in live environments, using Universal Software radio Peripheral (USRP) devices, the proposed algorithm has been thoroughly evaluated in terms of gained throughput, interference, range enhancements and power consumption. It has been observed, that 30 % increase in achieved throughput is possible, as compared to fixed width channel assignment. It has also been concluded, flexible channelization can simultaneously decrease power consumption and increase range. Both of these quantities are conflicting in fixed width scenarios and a trade off is required to be made for optimal performance. A similar tradeoff is also required for interference and coverage. However, use of flexible channelization can enhance coverage without increasing co-channel interference.