Chapter 12. Internet in Space
In this chapter…
In 1945, science fiction writer Arthur C. Clarke published an article called "Extra-Terrestrial Relays" in the magazine Wireless World. He described almost everything necessary to build a satellite network, including the radio spectrum needed, the solar panels to power it the geostationary orbit and even the type of rocked needed to launch the satellite.
Clarke himself was afraid that his ideas were "too farfetched to be taken very seriously,"but less than fifty years later they had gone from science fiction to a multibillion dollar industry. This progress was largely due to the invention of the transistor, and later to computer technology. Transceivers in the forties relied on valves, which needed to be replaced frequently, so Clarke's "relays" required astronauts to perform maintenance. Transistors meant that radios could be made smaller and more reliable.
Communications satellites, also known as comsats or birds, were for a long time the main means of transporting intercontinental phone calls. Satellites were owned by government agencies or specialized corporations, and dishes by the phone companies. Ordinary phone users had no contact with the technology, though they sometimes noticed a slight delay in conversations because of the time taken for a signal to get into space and back.
All that changed with the growth of the Internet and advancements in fiber-optics. A single strand of fiber can carry more information than every satellite ever launched, making it more economical to use cables. By 2000, several international consortia were planning to ring the world in fiber, even prompting talk of a "bandwidth glut." With their traditional role gone, satellites seemed to be in danger of obsolescence.
In the twenty-first century, the biggest application for satellite communications is as a local loop technology, similar to fixed wireless but covering a much larger area. Data is beamed directly to and from users, bypassing the phone company altogether.
There are also plenty of satellite-based mobile systems under construction, though these are running into difficulties. Constructing a phone that can find a satellite in the sky is a technical challenge. Most satellite antennas use a dish that is manually pointed towards the satellite and focuses its signals to a point. Satellite phones have to do without this, but still need a large antenna that makes them bulkier than regular cellphones.
The economic case of satellite-based mobile has also been undermined by the very thing that it hoped to cash in on—the popularity of mobile communications. With Earth-bound cellular networks so widely available, there are few major business areas where a satellite-based system is necessary. They are useful mostly in poorer countries, where few people are able to afford them.