During last week's FutureNet conference, Woojune Kim, Airvana vice president of technology, outlined why his company is still bullish on femtocell prospects. The company believes will come to see them as essential to offloading traffic on their mobile data networks as demand continues to grow.

For the uninitiated, femtocells are essentially small cellular access points that route nearby wireless voice and data traffic through preexisting broadband connections. In this way, femtocells can provide VoIP for wireless handsets that can both improve call quality and save money by letting users make calls without using up their cell minutes. Femtocells also have for carriers, as they let wireless companies offload traffic from their own networks and onto wired IP networks.

So far, however, carriers haven't been all that successful in selling femtocells to their customers. A recent report from research firm Infonetics Research found that vendors sold approximately in 2009, well below their expectations. Infonetics analyst Richard Webb said at the time that carriers have tried marketing femtocells to their customers by focusing on their ability to improve call quality within homes. The problem with this, Webb claimed, is that most people have strong call quality in their homes already and don't see the need to spend more than $100 on equipment to improve it.

However, Infonetics does see the femtocell market significantly picking up over the next few years, as the firm projects femtocell sales to rise to 40,000 units this year and 2.5 million units in 2011.