Femtocells: Is There Room For Them On Your Network?

Businesses are mobilizing an increasing number of applications, including e-mail and CRM. In a recent reader poll, 70% of respondents said they use mobile/wireless applications to access organizational data; communications mechanisms were fairly evenly split among Wi-Fi and cellular networks. Pervasive mobile coverage is clearly important, and femtocells are one way to ensure good inside cellular connectivity for customers and employees, even in locations where that's a challenge.

Much of the value and ROI of application mobility projects depends on pervasive connectivity. And without good cellular coverage, mobile applications are used less, which translates into a lower average revenue per user for carriers. In-building wireless systems, like newly conceived femtocells, can fill in coverage gaps, driving increased ROI for enterprises and average revenue per user for carriers.

There are many ways of boosting mobile coverage, including the use of passive repeaters, distributed antenna systems, and fixed- mobile convergence. Femtocells promise to let users roam onto an in-building network without a pricey dual-mode phone. A number of niche vendors have stepped forward with these products, and some big manufacturers are surveying the field. At an average cost of $150 to $200, a single femtocell could support four to eight users within a range of roughly 300 feet, depending on the power output of the femtocell and the physical characteristics of the site. Traffic can be backhauled over standard IP connections, like DSL or cable modems, yet let cellular phones obtain cellular access for both voice and 3G data.

The big disadvantage of current femtocells is their low capacity; picocells, which are more expensive but allow for greater per-cell call capacity, are useful both for providing indoor coverage for buildings with high user density as well as for boosting outdoor call capacity in a macro cellular network. And there's competition from Wi-Fi vendors. The progress being made toward fixed-mobile convergence within the enterprise means femtocells may have a tough time making inroads in this market.