A Study of Transmit Power Control for Wireless LAN using Channel Segregation Based Dynamic Channel Assignment

Wireless local area network (WLAN) has been rapidly spreading. Rapid increase in the number of access points (APs) increases the co-channel interference (CCI), thereby degrading the throughput performance. To mitigate the CCI problem, recently, we investigated the introduction of channel segregation based dynamic channel assignment (CS-DCA) into WLAN. CS-DCA is a distributed algorithm. Each AP has the channel priority table and periodically updates according to the CCI measurement. AP chooses a channel having the lowest CCI so as to minimize the CCI given to other APs. In this way, although CS-DCA is a distributed algorithm, it can form a stable channel reuse pattern. In our previous paper, we assumed an equal transmit power. By using transmit power control (TPC), stations (STAs) can avoid unnecessarily high transmit power, thereby reducing the CCI given to other APs. In this paper, we introduce the TPC to WLAN using CS-DCA. It is confirmed by computer simulation that CS-DCA with TPC can forms a stable channel reuse pattern and improves the signal-to-interference-plus-noise power ratio (SINR) further. Keyword Transmit power control, Channel segregation, Dynamic channel assignment, Co-channel interference, Wireless LAN