Ubiquitous coverage is particularly challenging considering that a considerable amount of usage is indoor. Poor network coverage affects simple phone calls as well as broadband data, but impact on the latter is typically the greatest, because of factors like frequency. Moreover, as consumption increases, capacity in the 3G radio network, which is shared among all users in a cell, starts to diminish, providing lower speed connections.

Fixing this requires more 3G infrastructure that can be very hard to justify economically. In short, operators struggle to viably deliver their promise to subscribers with a traditional 3G-only approach. The users, on the other hand, demand ubiquitous, secure, and economical wireless broadband that is easy to use (as shown in the figure below). In a sense, the best mobile broadband service network is one you never have to think about. It needs to be pointed out that users typically only want access to their applications, and are not usually concerned about the underlying radio technology used.

A cellular network enabling smartphone users to connect over the best available wireless network and seamlessly roam between them.

As broadband adoption reaches saturation and competition between operators heats up, ubiquitous mobile broadband coverage is an area where operators and vendors are working hard improve the user experience. The basic strategy is to leverage short range wireless technologies like Wi-Fi and so-called Femtocells (small in-home cellular stations), working in conjunction with fixed broadband networks, to improve indoor coverage and improve network capacity.

Wi-Fi is a widely accepted mainstream wireless network technology today that is found almost everywhere and offers high-speed network access. The challenges with leveraging available Wi-Fi networks have been the mobile device connection manager software.

Providing a seamless service offering while using two different radio networks requires more 'smarts' in the smartphone or mobile device connection manager than has historically been available, but this is changing quickly.

Network operators are also pursuing Femtocells to improve network coverage and capacity, but while they are not currently deployed on a large scale, femtocells offer coverage improvements for both voice services and 3G data services. Handover between femtocells and wide area macrocells is handled by existing mobile network mechanisms, so no special mobile device connection manager needs to be developed.

Making Wi-Fi and Femtocells a seamless part of the overall wireless access are helping improve mobile broadband coverage to users at the minimum cost. From a user point of view, lower cost delivery means lower data service subscription fees, greater "unlimited" data volume caps, or both.

Conclusion
Wi-Fi or femtocell short range wireless networks, in conjunction with innovative multi-access session management gateways, and improved mobile device connection manager software will ensure that subscribers get what they want: any service, anywhere, all the time. With a new generation of fundamental ingredients, the true mobile broadband experience emerges: the broadband service is always available, the application and content experience is consistent, and users are always connected.

About the Author
Ajay Sahai is director of product management at Stoke, Inc., a developer of mobile broadband access gateways for network operators. Before joining Stoke, Ajay worked at Azaire Networks, Lucent Technologies, Fujitsu Network Communications, and Hughes Software Systems. While at Fujitsu, Ajay was granted a US Patent for his work on Ethernet over SONET and RPR technologies. He holds a BSEE from the Institute of Technology, BHU Varanasi, India and an MBA from New York University