Wireless voice nets edge toward convergence

The firm boundary between Wi-Fi wireless LANs and broadband cellular voice networks is starting to blur.

At the CTIA Wireless conference in Las Vegas earlier this month, for example, the Wi-Fi Alliance and the CTIA cellular-industry association announced a partnership to develop certification programs for converged Wi-Fi and mobile WAN handsets. While lean on relationship specifics, the industry groups said they plan to test dual-mode phones for radio-frequency (RF) performance, interference, signal handoff, battery life and other issues. No time frame for testing was attached to the announcement.

However, such joint activity seems imperative if the cellular and Wi-Fi voice worlds are to be brought together successfully. Technical and business cooperation from both camps means users accessing both types of wireless phone connections and networks stand a better chance at experiencing no interruption in their voice calls as they roam.

Meantime, be sure to evaluate battery life as a key component in your dual-mode phone purchase considerations. Roger Entner, vice president of wireless telecom at international researcher Ovum, says that “the biggest obstacle right now for using Wi-Fi in a cellular phone is the almost-unacceptable battery drain. The minimum you’d expect from any wireless phone is up for 12 to 16 hours of standby time and two to three hours” talk time, he advises. Today’s dual-mode devices are “challenged to meet these criteria,” he says.

The IT director at a voice-centric Chicago wholesaler who has been piloting the CPE-based Enterprise Seamless Mobility solution from Motorola, Avaya and Proxim, however, says that the battery life of the Motorola CN620 handset supporting GSM cellular and Wi-Fi voice calls improved substantially last spring with a code revision.

“Most users can charge [their CN620] once a day; our 10 heaviest users always have a spare battery and they may do one battery change a day,” says the IT director. “There are have some high-capacity batteries available, but most people don’t like the extra weight.”