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Portable systems have definite application for wilderness remote ground communications that would be useful to persons and businesses located beyond conventional public telephone and cellular services. Whether for search and rescue, forest fire ground coordination, medical assistance or business and personal communications, the wilderness communications possibilities are many. Communications for a remote or seasonal temporary base of operations can easily be set up in moments at minimal cost, with the same ease of operation as found with a cellular telephone. With a portable, transportable or fixed site satcom, a lap-top PC and a printer, a business office can be set up in the most remote area imaginable. All of these systems can be powered by batteries, solar panels, generators (fuel or wind) or a combination of non-outside world power devices. For instance this past year this technology was used successfully by the Mt. Everest climbers to report on the success and tragedy of the May climb. Digital images (still pictures) were also provided from base camp using this equipment. Presently there are two satellite systems with networks in operation. Inmarsat, for global world wide use, and AMSC/TMI for regional North and Central America/Caribbean use. The Inmarsat system is an international organization, made up of 82 member nations including the U.S. and Canada and having four operational satellites. The AMSC/TMI system is operated by U.S. and Canadian public corporations and has two operational satellites. The technology for both systems are similar using geostationary satellites over the equator. In non technical terms, both systems can be described as functioning similar to cellular, but with no holes or dead spots anywhere in their designated areas of coverage except when the line of sight to the satellite is blocked by a building or other structure. As an example, If you envision a cell tower suspended in space 23,500 miles above equator instead of 200 to 500 ft towers on the ground, spaced every 15 to 20 miles you can get the idea of the broad coverage available under the “foot print” of the satellite. With cellular, as you move from under the “foot print” of one cell tower your transmissions are switched to the next in range. With a stationary satellite suspended in space, one satellite “foot print” covers about one third of the globe. With a cellular tower the “foot print” coverage is 15 to 20 miles. With the four international Inmarsat satellites the entire globe can be covered, and with the regional system (AMSC/TMI) continental coverage is uninterrupted between Venezuela and the Arctic. In any area covered by the particular system, you can complete voice, fax and data calls from, or callers can contact your satellite phone no mater how remote the location, as easily as making the same call on a public phone system. Small portable satellite telephones for global use can be obtained for approximately $4,500 U.S. dollars with air time of about $3.00 per minute. This rate is for connecting a call to anywhere in the world from wherever the satellite phone is located. There are no additional roaming or long distance charges. A portable phone for regional continental use, while similar in equipment price, cost somewhat less to operate if your calls are terminated in North America (U.S. and Canada), about $1.35 a minute. For calling outside of the U.S. and Canada additional long distance charges are added. Other more expensive and larger transportable systems are available in rugged shock resistant versions, some with higher data rates for telemedicine and video purposes. If you do not require mobility, such as a permanent work site, lodge or hunting camp, fixed site systems with high gain dish antennas are the most economical for use on the regional system. Today there isn’t a place on earth, between 76 degrees north and south latitude, that telephone, fax and e-mail communications can not be accomplished as easily as from your home or office telephone. |
