Abstract
Today, we find a large number of wireless networks based on different radio access technologies (RATs). Every existing RAT has its own merits. Now the focus is turned towards the next-generation communication networks (Akyildiz, Mohanty, & Xie, 2005), which will seamlessly integrate various existing wireless communication networks, such as wireless local area networks (WLANs, e.g., IEEE 802.11 a/b/g and HIPERLAN/2), wireless wide area networks (WWANs, e.g., 1G, 2G, 3G, IEEE 802.20), wireless personal area networks (WPANs, e.g., Bluetooth, IEEE 802.15.1/3/4), and wireless metropolitan area networks (WMANs, e.g., IEEE 802.16) to form a converged heterogeneous architecture (Cavalcanti, Agrawal, Cordeiro, Xie, & Kumar, 2005).