Globalstar I would describe as a multi-regional system, in that technically the coverage is split into regions. It is not truly global. The design of the system appears to be dependent on relatively local ground stations to carry the telephony traffic in order to provide coverage in particular location.

As at Summer 2005, coverage includes most of both Americas, Europe, Middle East, northern Asia, Australia and New Zealand, with notable exceptions (most of Africa, India, parts of Far East, many ocean areas, poles). For precise details, check the Globalstar website.

The system is a low earth orbit one, with the satellites orbiting approx 500 miles above the earth. The advantage of low earth orbit is that the signal paths to the satellite are much shorter than for geo-stationary satellites, which are located over the equator. This also enables polar coverage, although actually Globalstar does not provide coverage over about 72 degrees latitude north or south.

I tested a Telit Satelit 550, which is a GSM-900 and Globalstar dual mode phone. I used this with my Vodafone UK SIM card (as opposed to a Globalstar SIM). There is also now a newer Satelit 600 phone and Qualcomm make Globalstar phones that are compatible with some American cellular networks. The 550 was the only one I tried.

Photos of the handset are shown. The handset is quite long (the newer model is shorter) but it's quite light and the satellite antenna when stowed folds nicely into the battery at the back. Operation of the menu is OK but is probably the least straightforward of the three phones I tried. Rather ominously, the hire phone was supplied with not just one but two spare batteries, and indeed the battery life is not exceptional with bars disappearing off the battery charge indicator even after short calls. The Satelite 550 has been replaced with a new model, the 600, this may have improved performance but I've not tested it. All the Globalstar handheld phones seem to list fairly low standby and call times on the batteries.

Upon power on, outdoors the phone logs reasonably quickly on the network. Testing in the UK it usually locked to the French gateway but sometimes other indications would appear in the display which was confusing. Once or twice the network signal dropped out and didn't return, even in the open, I had to switch the phone off and back on again. Call clarity was very good when I tried it.

Globalstar is like GSM in the sky, with many of the usual features such as SMS text messaging.

Globalstar offers roaming with other operators which is an advantage. Check the www.gsmworld.com website or with your operator to check whether they have a roaming agreement with Globalstar. As far as I'm aware in the UK, only Vodafone UK have a roaming agreement with Globalstar, the others do not.

Good points:

- Call clarity, widespread multi-regional coverage on Low Earth Orbit satellites, with roaming available for Vodafone UK and other countries GSM/CDMA users (subject to roaming agreement). Some Globalstar calling rates look very good - in some cases cheaper than GSM roaming.

Bad points:

- Poor battery life on handset (the model I tried), not a truly global system with some odd coverage gaps.

Pictured: front of phone with antenna raised (the stub antenna is the GSM one), back of phone with battery removed, showing SIM card slot, back of handset with battery on, close-up of display (phone is 'Searching GW' (gateway), with envelope icon indicating text message, one bar on battery counter, and clock.

Diskette is pictured with Globalstar phone to give an idea of scale, it is not part of the Globalstar kit.