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Mobile

Jumping from satellite to cellular and back

A quick new wireless data service combines the worldwide reach of satellite networks with a cellular setup's ability to steer signals through the architectural canyons of big cities.

A quick new wireless data service combines the worldwide reach of satellite networks with a cellular setup's ability to steer signals through the architectural canyons of big cities.

London-based Inmarsat's Regional BGAN service, announced Tuesday, is the second to merge satellite and cellular phone networks. Globalstar Telecommunications has been selling hybrid cellular-satellite phones and services for some time. But Inmarsat's service can deliver data at 176kbps, about twice as fast as Globalstar's, according to both companies. Unlike Globalstar's service, however, Inmarsat's modem-based Regional BGAN is limited to data-specific tasks such as Web surfing and getting behind a corporate firewall; it does not handle voice calls.

The Inmarsat offering consists of a satellite modem that can be used with laptops or PCs. When subscribers want to jump from the satellite network to a cellular setup, they simply remove the subscriber identity module card from their cell phone and plug it into the modem. Thumbnail-size SIM cards are inside all cell phones based on the Global System for Mobile Communications (GSM) standard. The cards carry the account information needed to log onto a GSM carrier's network.

Cellular and satellite phone companies are mixing networks to strengthen each other's coverage areas. Satellite phones work virtually anywhere in the world, but the concrete and steel caverns of cities tend to muddle the satellite phone signal. Cellular telephone networks are at their strongest in urban areas.

"In some places, cellular is the answer, in some places, satellite is the answer," said Globalstar representative Mac Jeffery.

The biggest knock against satellite services is their cost. On the voice front, satellite phones are hundreds of dollars more than their cellular counterparts. Plus, calls cost between $2 to $5 a minute, while most cellular telephone calls are just a few pennies a minute. There have been some recent price breaks--most notably from Globalstar, which cut U.S. satellite phone calls to 17 cents a minute and lowered the price of its hybrid phone to $600--but heavy price tags remain the norm.

The modems needed to use Inmarsat's Regional BGAN service cost a hefty $1,500 each, and subscribers will pay $10 to $15 for every megabyte of data they download, according to Inmarsat director Johnny Nemes. By comparison, Sprint PCS's new cellular-based PCS Vision wireless Web service runs $40 for 20 megabytes of downloads--that's $2 per megabyte.

Nemes acknowledges that hybrid services aren't for everybody--not yet anyway. Until competition drives down the cost of equipment, Regional BGAN will generally attract only pipeline builders, defense contractors or other mobile pros that must be in touch with an office's network regardless of where they are, he said.

"This is for the platinum credit card set," said Alan Reiter, an analyst with consulting company Wireless Internet & Mobile Computing.

Inmarsat's Nemes said 10 GSM carriers are selling Regional BGAN. None of the carriers are in the

Cellular industry entrepreneur Craig McCaw's ICO Global Communications is also said to be working on hybrid satellite-cellular devices.