Performance Evaluation of an IEEE 802.11 af Prototype in a Suburban Environment

The demand for more spectrum has been evident as wireless technology becomes a necessity. To address the impending problem of spectrum scarcity, the Federal Communications Commission (FCC) allowed the utilization of the unused TV spectrum - technically referred as TV white space (TVWS) to the secondary unlicensed users (SUs) with a high emphasis on interference protection of the primary licensed users (PUs). Several standards have been developed to govern its usage, one of which is the IEEE 802.11af standard which enables wireless local area network (WLAN) to operate in the TVWS. To model the aforementioned system, this study develops an empirical model based on the log-distance path loss model and throughput performance evaluation of an IEEE S02.11af prototype in a suburban environment. The outdoor experiment were carried out on a 15m wide pathway beside a football field which extends over 100 m conducting RSSI and throughput measurements. Result shows that the obtained path loss coefficient n is close to the free space condition. It has been found out that the throughput performance of the system, taking into account the moving obstacles i.e. vehicles and passerby, significantly improves with lower MCS value and higher received power. Interestingly, a surge in throughput performance was observed at the street corner due to the constructive interference experienced by the channel. The overall performance of the device shows strength over the existing IEEE 802.11 systems in terms of path loss and throughput.