Satellites play a vital role in today’s military operations, and not surprisingly, in commercial maritime operations as well. The benefits of satellite communications for the military and maritime industries include the use of the Global Positioning System, or GPS, and secure worldwide communications. Not only does this technology help the U.S. Navy and commercial maritime operations navigate and share information, but the U.S. Coast Guard and Air Force use it to aid in search and rescue missions. Here are a few ways satellite communications are being used by both groups.
Milstar stands for “military strategic and tactical relay” and it is comprised of a network, or a “constellation” of SatComs in geostationary orbit. The primary purpose of this constellation is to give the military a secure communications network that is jam resistant, or protected against signal interference. Milstar’s satellites did not come cheap. Built by Lockheed Martin at a cost of roughly $800 million apiece, they were designed to last for 10 years in orbit. Intended to transmit highly sensitive military communications, they were engineered with low data-rate bandwidths up to 4.8 kbit/s. To make data difficult to detect and intercept, the Milstar satellites can transmit encrypted communications between satellites or between terminals on the ground. Milstar serves all branches of the U.S. Military.
In addition to transmitting top secret communications for the U.S. military, satellite navigation, or SAT NAV provides information on geo-spatial positioning anywhere on the globe. Satellite navigation enables GPS units of all sizes and provides the user with the longitude, latitude and altitude of their location. In order to achieve global coverage, 20-30 MEO’s (medium Earth orbit) satellites are used and spread across various orbital planes.
SatCom Aids Search and Rescue
Satellite enabled global positioning systems have evolved to aid search and rescue operators in and out of the U.S. military. NASA’s SARSAT, an international search and rescue satellite program, helps save hundreds of people stranded at sea or on land every year. In the 30 years this program has been operational, the number rescued has reached the thousands. The SARSAT technology detects distress signals sent out by small beacons and relays the signals to ground stations. The Coast Guard or appropriate agency can then be contacted to initiate rescue efforts.
Advanced Extremely High Frequency
AEHF is the name of the satellite communications constellation used by the U.S. Air Force Space Command. Incorporating the low data-rate signals used by Milstar, AEHF transmits secure communications without sending them to a ground station first. They can also transmit at high data rates up to 8 Mbit/s. The launching of AEHF satellites provides greater communications capabilities and more efficient performance for all branches of the U.S. Military.
For shipping vessels out to sea for weeks and months at a time, satellite communications are the vessel’s lifeline to the world. Satellites enable internet, phone and television transmissions at sea with the installation of fixed, mobile or portable dishes. Of course, GPS technology is just as vital to shipping vessels as it is for military vessels, helping ships navigate across the globe and locating their position in an emergency.
Satellite communications have evolved into technology of the highest order, and the future will only see more of these amazing inventions sent into orbit.