Special issue on heterogeneous networks

For more than three decades, wireless networks have proliferated and have transformed the way we interact, live and do business. From the 1st generation analog network, supporting voice-only bulky portable phones for cars, to the 4th generation of Internet-oriented networks, supporting all sort of sleek multi-media devices such as smartphones, tablets and netbooks, the evolution of wireless networks has been one of the most striking successes of information technology.