Downlink subchannel power allocation for multicell WRANs considering inter-cell interference

OFDMA modulation is utilized for downlink and uplink communications in IEEE 802.22 wireless regional area network(WRAN). Because a base station (BS) uses omnidirectional antenna for downlink communications, BS will interfere with consumer premise equipments (CPEs) which use the same subchannel in other cells. Every BS wants to maxmize its sum downlink rate when minimizing co-channel interference with other cells. This can be seen as a noncooperative game. We have proved the game was an exact potential game (EPG) and found potential function. We use distributed iterative waterfilling power allocation (DIWPA) algorithm to find Nash equilibrium (NE) of EPG. Simulation result indicates DIWPA can achieve more dowmlink rate in evidence compared to the way which is called average power allcation (APA) algorithm.