Thuraya is really a regional system, based in the Middle East (UAE). Unlike for Globalstar and Iridium, Thuraya uses a satellite in geo-stationary orbit. This is located at 44 degrees east, which is basically 22,000 miles above the equator (over Ethiopia). Coverage extends from Iceland in the west, over Europe and Western Russia, Middle East, India, Pakistan, Bangladesh, and the northern half of Africa. (For current coverage, see the Thuraya website). There are plans to site a more easterly satellite to cover the remainder of Asia, but this is not yet in place.

A disadvantage of using a geo-stationary system, located over the equator, is that elevation angles (angle that satellite appears to be, above horizon) decrease as you proceed further north, south, and to the easterly and westerly limits of the satellite coverage). This is not a problem in the core coverage area such as Middle East as the elevation angles will be quite high with the satellite appearing high in the sky, but the further north/west/east/south, the more likely you are for direct line of sight to the satellite to be obscured. Trying the system in North Wales, UK, in the mountains there were places in valleys I could not get a signal due to obstruction to signal path by mountain peaks - a low-earth-orbit system would not see such problems.

The joy of this network is the light, compact, and well-designed handset, made by Hughes, which at 220 grams is not much bigger than a conventional cellular phone. It fits in a shirt pocket. Surveying prices, to buy it is about half the price of an Iridium or Globalstar handset.  Most of the satellite antenna tucks into the body of the phone when not in use. The existing phone is a dual mode GSM-900 / Thuraya mode phone. All the UK GSM operators have roaming agreements with Thuraya but only Vodafone and O2 users can use the GSM-900 part of the phone on their home network (Orange UK and T-Mobile UK being GSM-1800 and 3G only). Since reviewing this phone, Thuraya have announced a new model which will have multi-band GSM capability. I used the phone with a Vodafone UK SIM card. All the existing phones have a GPS unit built in, which I guess because Thuraya is a single satellite system effectively, is needed for the phone to tri-angulate it's position. However having GPS is often a useful separate feature on it's own for those people travelling to remote locations.

Upon power up, the phone takes a long time to acquire the network (about a minute) and you need to be in direct line of sight to the satellite. The wait becomes a bit of a bore, but I think it's necessary for the phone to work out it's position by GPS. Call quality was OK, no problems making/receiving calls, within coverage.

When out of line-of-sight to the satellite, Thuraya have an excellent 'high power alerting' system. Most cellular networks only have two coverage statuses, either you are within coverage, and your phone has two-way contact with one or more base stations, or you are out of coverage, with no two-way contact. Thuraya has this third, intermediate level, where it effectively acts as a pager, listening to a high power alerting signal. If a call comes in, the caller just hears a ringing tone, but the phone does not ring, it gives an alert, telling the user to move to proper line-of-sight in order that the call can be initiated. If the call cannot be connected within one minute, then the incoming call is unsuccessful.

The high power alerting often works when the phone is indoors (I found it helps to leave the phone next to a window, although it didn't matter which direction it pointed in), disadvantage was that if the phone does not 'hear' the high power alerting signal for more than about 2 minutes (you see an indication of signal strength in the display), it stops listening, and does not seem to try to re-gain the network, even when back in coverage. I can't see any point for it stopping listening (waiting for incoming calls), unless it is a battery-saving measure, because the phone may subsequently be moved back into coverage.

Thuraya really is like GSM in the sky, with many of the usual features including SMS text messaging. I was able to use the *#147# (Vodafone) feature to check last incoming call number, and change call divert settings.

Good points

- above all, the handset, very compact and easy to use. High power alerting enabling notice of incoming calls, even on some occasions when handset is indoors. Lower cost of handset compared with Iridium and Globalstar. Widespread roaming agreements with GSM cellular operators. Very good system for use in central coverage areas, such as Middle East, most of Africa.

Bad points

- handset drops out of high power alerting mode after a couple of minutes of not receiving any signal, and doesn't re-register. Slow to register on network each time. Towards the edge of the coverage area, elevation to the satellite is lower, resulting in shadowing in some locations and resulting lack of coverage.

Pictured (from top): close-up of phone connected to network, high power alerting with signal bar in top right of screen, connected handset, back of handset, handset searching for network (NB antenna should be raised for this function), a typical Thuraya hire kit.

NB diskette pictured is not part of hire kit, but there to give an idea of scale.

Map below shows azimuth and elevation look angles to Thuraya 44 degrees East satellite - note that coverage area is not overlaid, for this see the Thuraya website.