30 Years of Communications Technology
- Thursday, 04 January 2007
In the early 1960s, the International Telecommunications Satellite Organization (INTELSAT) provided telephone circuits for the NASA Communications Network (NASCOM). By the end of the decade, the INTELSAT III series reached global coverage, just days before a halfbillion people watched Neil Armstrong set foot on the moon.
Over the past 30 years, more and more satellites have been launched into orbit, primarily for television and telephone service. But in the 1970s, the U.S. Department of Defense created a military system of NAVSTAR (Navigation Signal Training and Ranging) satellites built by Rockwell International, each the size of a car and weighing close to 2,000 pounds. Called the Global Positioning System (GPS), the satellite network would revolutionize how we communicate.
The GPS network, completed in 1995, initially helped soldiers communicate with each other and their bases, and was a military navigational system. In 1996, recognizing the importance of GPS applications to civilian society, President Bill Clinton issued a directive that made the GPS network available as a national asset.
The original GPS was made up of 18 satellites, six in each of three orbital planes, and their ground stations. Today’s system consists of 24 satellites, each orbiting the Earth every 12 hours in a formation that ensures that every point on the planet will always be in radio contact with at least four satellites.
In the past 10 years, the GPS has improved the effectiveness and security of our military forces, and has changed the way we communicate with each other, our cars, airplanes, computers, and anyone or anything else equipped with a GPS receiver.
One of the fastest-growing civilian uses of GPS is the automotive market. In 1996, General Motors introduced OnStar, a hands-free in-vehicle communications system using GPS and cell phone technologies. Today, most major automakers offer in-vehicle navigation and communications capabilities based on GPS. These systems enable the transmission of data communications between the car and a central server location, giving drivers the ability to communicate with a live person 24 hours a day in the event of an accident, breakdown, or other type of emergency.
Virtual Reality & Interactive Training
While many people think of virtual reality (VR) as video games and movie special effects, the technologies that form the basis of virtual reality are rooted in scientific visualization. Before the 1980s these technology elements existed, but once high-performance computers became more commonplace, virtual reality became a popular form of interactive communication. Today’s applications of VR technologies include immersive training and simulation, and scientific visualization in areas such as telesurgery and telerobotics.
Immersive VR training and simulation employs a number of technologies that, when combined, enable the users to communicate in a three-dimensional environment. Head-mounted displays (HMDs), high-resolution video screens, audio, and data input devices such as data gloves and other tracking devices can all be used to communicate a particular environment. The HMD presents a stereoscopic view of the computer-generated environment, and is used extensively in military flight training simulators and in VR surgical systems. The military also incorporates HMDs as part of advanced soldiers’ helmets, providing nightvision capabilities, two-way communications, and intercoms.