Effects of Co-channel Interference in WLAN and Cognitive Radio Based Approach to Minimize It

WLAN uses frequency spectrum for providing wireless access to nomadic nodes which is in fact a very scarce resource. One common issue in deployment of a multi-channel multi-AP wireless network is interference. One of the reasons why theoretical throughput (54 Mbps for 802.11g) can't be achieved is co-channel interference. In this paper, the effect of co-channel interference on data throughput has been studied in a practical multiple AP (access point) scenario. Interference can be minimized by adjusting the transmission power. This paper also provides an algorithm for transmission power adjustment of APs by using the concept of cognitive radio, which eventually helps in minimizing co-channel interference.