Article about [iridium satellite phones]

[Iridium satellite phones] are a global satellite communications company that have a wide network covering the entire earth including the vast ocean regions, the most airways and mountain ranges and polar circles such as the arctic-(Greenland, Iceland and upper regions of Canada) and the Antarctic. [Iridium satellite phones] have a worldwide network of 66 satellites and hence have a global network spanning different continents. Most phones are large in size due to a more complex phone machinery and also have a stronger interior parts assembly, and rigid frame and body due to their wide use. [iridium satellite phones] are much in use by researchers in the ocean regions, mountaineers and hitchhikers covering mountain tops, explorers and scientists in the Antarctic and arctic poles, game enthusiasts, travellers and researchers in Africa, businessmen travelling different continents and mostly by people covering vast places and requiring ranges which are out of reach and also connectivity in such places. It is also used by wild life photographers travelling in the deep jungles of Latin America, Africa, Europe, Russia, china and south East Asia. Satellite phones use geostationary orbit with three or four satellites. Inmarsat is the most popular among civilian iridium satellite phone systems. This has large dishes for signal reception and transmission. They are the best way of communicating from places where there are no communication systems or modes of contact with the rest of the world. New iridium phones retail for $1375 and old ones for $599. The satellites also in low orbit at a height of about approximately 485 miles and an inclination of 86.4. Orbit speed of such phones are about 17,000 mph. Communication also happens through Ka band inter-satellite links. One given satellite may have four inter-satellite links. Two neighbours satellites and others in the same orbital pane, and two satellites in neighbouring planes. The satellites orbit from pole to pole in about 100 minutes. This also means better visibility and service reception at the north and south poles, when few customers are being served. Over-the-pole orbit design makes layers when satellites in opposite rotating planes are travelling in opposite directions. Interlinking satellites have to also move faster with large Doppler movements. Satellites moving in the same direction and inter-linked are the ones supported by iridium. Satellites which have failed in orbit include Iridium 28 and Iridium 33. Iridium Next is a newly defined second generation currently use with its 66 satellites. Data transmission is a new feature in such systems not present in previous systems.