Downlink Capacity of Super Wi-Fi Coexisting with Conventional Wi-Fi

Abstract

Super Wi-Fi is a Wi-Fi like service over TV white spaces (TVWS) based on the dynamic spectrum access (DSA) technology. Although Super Wi-Fi is expected to achieve larger coverage than conventional Wi-Fi thanks to the superior propagation characteristics of TVWS, it suffers from smaller bandwidth than Wi-Fi (6-8 MHz versus 20 MHz) which degrades network capacity. Therefore, it is common belief that the two Wi-Fi technologies may target different applications such as Super Wi-Fi for coverage and Wi-Fi for speed. However, there is a lack of studies that rigorously analyzes and compares the performance of Super Wi-Fi and Wi-Fi to confirm such belief. To fill the gap, this paper performs a thorough analysis on the capacity of Super Wi-Fi under the scenario that a Super Wi-Fi access point (AP) coexists with a Wi-Fi AP. Comparing the downlink capacity of Super Wi-Fi and Wi-Fi reveals that Super Wi-Fi can outperform Wi-Fi at the outskirts of the Wi-Fi's coverage and Super Wi-Fi gets more beneficial when channel bonding is employed. In addition, the maximal coverage radius of Super Wi-Fi is derived with which Super Wi-Fi can achieve better average capacity than a network of densely-deployed Wi-Fi APs, where the maximal radius is up to 3.2 times larger than the coverage radius of Wi-Fi.