At the start of the 21-century  the wireless mobile communications are going to witness unprecedented growth fuelled by an information explosion and  a  technology revolution in the form of Third Generation (3G) mobile  wireless communications. The  first generation wireless mobile systems were analog and insecured. The present second generation systems are digital, secured but limited to a certain geographical area due to different technology standards by different countries. While these proposed 3G systems are sophisticated, Globally compatible and offer significant improvement of data and multimedia capabilities. 03+Global roaming with a single system provided with large bandwidth, guaranteed by quality of services, ease of deployment coupled with recent advancements in semiconductor technologies for wireless applications make 3G wireless systems very attractive than that of first and second generation systems. Many  enabling technologies including wideband  code division multiple access, software defined radio, packet switched programmable intelligent networks, networks with distributed data storage offer a variety of services like wireless mobile internet, mobile multimedia Applications, mobile video telephony along with voice communications while roaming through different network standards.