Foundation of Computer Science
Spectrum scarcity is known to be main obstacle to scaling of wireless network capacity. Spectrum sharing is a solution to this problem. The unlicensed ISM (Industrial, Scientific and Medical) band is getting crowded by WLAN (Wireless Local Area Network) and WPAN (Wireless Personal Area Network) users and devices. Spectrum sharing within the devices of same network is not a problem. But coexistence of WLAN and WPAN (e.g.: Wi-Fi and ZigBee) is a challenging problem. Spectrum sharing among these networks will surely improve spectrum utilization. Wi-Fi and ZigBee uses 2.4GHz ISM band.