Over the last few years the use of satellite phones has been on the increase. They are now cheaper and more readily available than ever. However, this has not made it any easier for the consumer. With the choice of products on offer, how do you know which is the right one for you?
Popular Satellite Systems
Four satellite systems that have gained widespread popularity are Inmarsat, Iridium, Globalstar and Thuraya. Although they are all attempting to meet the same demand, they each go about it in different ways. Here's a basic overview of some of their strengths and weaknesses.
Inmarsat
The first mobile satellite system, Inmarsat is a great example of how the technology has emerged from a niche market and been made available to all. Originally designed for the maritime industry, they now have over 100,000 registered satellite terminals.
The Inmarsat Satellite Network
The Inmarsat network consists of four geo-stationary satellites 35,600km above the earth. The satellites are positioned at equatorial points over the Indian Ocean, the Pacific Ocean and the Eastern and Western sides of the Atlantic. The footprint created by this configuration is able to provide almost total global communication coverage with the exception of the North and South Poles. The first advantage that this gives Inmarsat is, once a signal is sent to a satellite, its individual footprint is often large enough to deliver that signal to its destination without having to transfer via another satellite first. This minimizes the risk of the signal being lost.
The main criticism that has been leveled against Inmarsat terminals is their size; they can be as big as laptop computers. Inmarsat rivals, Iridium, Globalstar and Thuraya, use handsets that are far more akin to cellular phones, which are handheld and do not need to be set up in a fixed location.
Inmarsat’s B–GAN Terminals
Inmarsat have now expanded their service with their next generation satellite system, B–GAN (Broadband Global Area Network). B–GAN delivers simultaneous voice and broadband through one single truly portable device.
Iridium
Iridium's mission was to create a satellite service that would provide truly global coverage, a service that no other satellite provider can currently provide. The Iridium system is the only provider of truly global voice and data solutions with complete coverage of the earth (except for Poland, Hungary, Sri Lanka and North Korea who have declined to support the service for political reasons). The Iridium satellite system provides global service across all ocean areas, air routes, and all landmasses, even the Poles
The Iridium Satellite Network
To achieve global coverage, the Iridium network uses 66 satellites, 450 miles high, orbiting the earth on 6 different planes. Traveling at 16,832 miles per hour, each satellite is able to circle the globe every 100 minutes. This configuration ensures that an Iridium handset will be able to send and receive calls from any location on the planet. As long as the handset has a clear line of sight to the sky, it will maintain communication with at least two satellites at any one time.
Iridium utilizes a portable handset with a large retractable antenna. Although still rather larger than a regular cell phone, the Iridium satellite unit is handheld and easy to carry. Whereas the Inmarsat satellite phone needs to be set up in a fixed location, the Iridium system even allows you to walk and talk.
Globalstar
Please note that Globalstar are currently experiencing problems with their satellites. This is resulting in some severe disruptions to service. As a result of this, Iridium is recommended as a handheld satellite phone solution.
The Globalstar network was developed with the business traveler in mind. Globalstar envisioned their customers as people who were working on the fringes of cellular networks, crossing in and out of coverage areas. Therefore, they designed their handset to work on the cellular CDMA networks as well as the Globalstar satellite network. There are 48 Low Earth Orbiting satellites which orbit the earth at an altitude of 875 miles.
The handheld phones are designed to switch seamlessly between the cellular networks and satellite network, even during a call. The phone will always use cellular networks if available. Only when there are not available will they link to the satellite network. By using this method the idea was to offer the best cost effective service, you would only use the more expensive satellite service when there was no alternative, (note though that roaming rates can be high with the cellular service).
Unfortunately, Globalstar has a limited coverage area. By operating on the CDMA standards, they have limited themselves to the localities where those standards are supported. At the moment, coverage includes the Americas, Russia and parts of Asia. Likewise their satellite network coverage area is limited compared to that of its rivals. Globalstar only offers service in around 100 countries, their territorial waters and some mid-ocean waters.
Thuraya
Thuraya offers dual band handheld phones operating on GSM cellular networks and Thuraya’s satellite services. Thuraya has roaming agreements with over 200 wireless cellular operators around the world, providing its customers the ability of using their Thuraya phones outside of satellite coverage.
Like Globalstar’s, Thuraya’s coverage is limited. There are 2 satellites in geo-synchronous orbit providing coverage in approximately 110 countries in Europe, parts of Africa, Asia, the Middle East and Australia.
In Summary
This information is not intended as a definitive guide to satellite phones. Rather, it is meant as a brief introduction to some of what is available. As you can see from the three examples highlighted, there is not one all encompassing system that can outperform its rivals in all areas. Each has certain strengths and certain weaknesses.
If you decide that you need to use a satellite phone, you need to decide which satellite network is best for you. You must assess which functions are most valuable to you. Do you need total global coverage? Do you need the ability to send and receive data? Do you want something that is easy to carry?
Once you are clear what you expect from satellite communication then you are able to make your decision from a more informed and confident position.
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