GSM To Follow CDMA In Push-To-Talk

By Joseph Palenchar On Apr 7 2003 - 6:00am

Push-to-talk (PTT) service from U.S. GSM carriers will follow the launch of push-to-talk service by U.S. CDMA carriers, according to multiple announcements at the recent CTIA show.

During the show, CDMA carrier Sprint PCS said it plans a late-year launch of PTT service, and Verizon said it hopes to offer PTT service by the end of the year over its CDMA network. Neither carrier offered details.

A GSM PTT solution, however, won't be commercially available to carriers until sometime next year, according to Nokia. At the show, Nokia demonstrated what it said is the first announced GSM PTT technology to date. It's a voice-over-GPRS technology that Nokia is developing in conjunction with Ericsson and Siemens. All three manufacturers plan technical trials in the second half, with availability of commercial infrastructure solutions and handsets in the first half of 2004, Nokia said.

During the show, Nokia used a modified EDGE phone to demonstrate the solution, which delivers a "fully acceptable" less-than-two-second delay between the time one subscriber talks and the other subscriber hears, a spokesman said. There is also a one-second interval between the time a subscriber pushes the PTT button and the time the handset beeps to signal that he can begin talking. The interval represents the time it takes for the handset to acquire a GPRS time slot, Nokia explained.

GSM carriers AT&T Wireless and Cingular said they support the efforts by the three manufacturers, which are jointly developing specifications that they will submit to standards bodies for approval.