Tuning In The Global Village : And Now, for a Word From Our Future . . . : We’ll use pizza-sized dishes to capture hundreds of channels, or play games with friends and shop from department stores via TV.

Harold Rosen, a vice president at Hughes Aircraft Co., has vivid memories of the first time a satellite was used for commercial television broadcasting. It was 1964, the event was the Tokyo Olympics, and he was helping set up the satellite Earth station at Point Mugu.

“We received it with this giant installation,” he recalled. “The dish was 85 feet in diameter . . . it cost millions.” Attached to the dish was the world’s most sensitive receiver, a liquid-helium-cooled contraption designed to “hear” the extremely faint signal being collected from the sky.

Since then, Rosen estimates, television broadcasting satellites have become one million times more powerful. Some satellite signals can now be captured on window-mounted dishes the size of a pizza.

New methods for “compressing” video signals will soon allow a single satellite channel to carry as many as two dozen separate TV programs. Despite rocket explosions and other technical failures that turn $100-million satellites into worthless chunks of metal from time to time, the Earth’s orbiting infrastructure grows fancier by the day.

Indeed, video compression, high-powered satellites and a variety of other advanced technologies will spur the development of a flood of new global TV services that national governments will be powerless to resist. In wealthy countries, new satellites and fiber-optic cable systems will give consumers access to hundreds of regular channels and thousands of “pay-per-view” programs. New “interactive” TV systems will prod couch potatoes into action with games, educational programs and home shopping services. High-definition television (HDTV) will bring cinema-quality pictures to wall-mounted “flat-panel” TVs.

Most poorer regions of the world won’t be able to afford such exotica for some time. But they will see a dramatic expansion of their television choices as new international satellite systems rain easy-to-catch signals down from the sky. While a back-yard satellite dish in, say, Southeast Asia might provide access to half a dozen channels today, it may be able to receive dozens if not hundreds of programs by the second half of this decade.

“Video compression is really going to change everything, and it’s going to change it quickly,” enthuses Mark Long, publisher of the World Satellite Almanac. “Two years from now, we’re going to be looking at a totally different communications system.”

At Hughes’ cavernous satellite-building facilities in El Segundo, some of the key components of this new television system are now under construction. Two of the company’s next-generation satellites will be used to beam 150 channels of programming directly to American homes beginning in 1994. Another is being built for maverick U.S. satellite entrepreneur Rene Anselmo, who plans to place it over the Pacific and thus expand the variety of programs available in Asian and Pacific nations. Yet another will become part of the Astra satellite network, which has made the home receiving dish commonplace across much of Europe.

All of these “birds” have one big advantage over their predecessors: more power, which translates into stronger, easier-to-catch signals and smaller, cheaper and harder-to-outlaw receiving dishes.

Complementing the increased power is video compression, which takes place not on the satellite itself, but in the equipment used to convert a picture into a television signal and then back into a picture. The key breakthrough is the replacement of traditional “analog” technology, in which an image is represented by an undulating electrical wave, with “digital” transmission, in which the same image is converted into the ones and zeros of computer code.

A TV channel--whether it’s on a satellite, a cable system, or a regular Earth-bound broadcast--is like a pipe that’s built to carry a single analog signal. Digital technology uses the same pipe to transmit ones and zeros. But a rapidly expanding bag of mathematical tricks makes it possible to dramatically reduce the number of numerical bits needed to represent the image. Thus anywhere from four to 24 digital channels (the number varies according to the type of program and the picture quality required) can be squeezed into a single analog transmission pipe.

With annual lease charges for a single transmission channel on a popular satellite running as high as $10 million a year, the economic appeal of digital compression is obvious. It can be used either to deliver programming to cable operators or broadcasters--who then retransmit it in the traditional manner--or to send programs directly to the home.

“Digital video compression immediately changes the ballgame in terms of what you can deliver,” says H. Allen Ecker, chief technical officer at Scientific Atlanta, a vendor of satellite TV transmission equipment. Cost savings from compression, he says, will enable programmers to offer new services that would otherwise be uneconomical. Traditional fare such as sports and movies will thus reach a much wider audience, and new uses of television--for education and business communications--will suddenly become practical.

Digital systems do, however, require expensive new equipment. Program distributors will need to digitize the pictures, and consumers receiving compressed video directly into their homes will have to buy sophisticated set-top computers to unscramble the blizzard of computer bits.

Also, the technology is still in its infancy, and changing rapidly. Suppliers such as Scientific Atlanta, General Instruments, Compression Labs, Thomson S.A. and Philips N. V. are all scrambling for orders with incompatible digital compression systems that have yet to prove themselves in day-to-day broadcasting operations.

“We’re still in the learning phase in the application of digital technology,” says Stan Baron, managing director for technology development at NBC Television. “There’s obviously a cost benefit. But we haven’t seen anything that meets all of our expectations.”

Still, many broadcasters are pushing ahead anyway--especially for new services that will require new equipment. And few doubt that digital transmission will dominate the skies by the middle of the decade.

Less certain is the market for advanced TV services--notably high-definition television and so-called interactive television--that are also far more practical because of digital technology.

HDTV promises a vast improvement in TV picture and sound quality. But the analog HDTV system initially developed in Japan has stumbled in the face of high prices and the refusal of U.S. and European regulatory authorities to adopt it as a standard.

Now, a group of mostly American companies is racing to develop digital HDTV in a competition organized by the Federal Communications Commission. The contest has produced many important advances in compression technology, but many experts now believe that widespread deployment of HDTV won’t begin until the late 1990s.

Interactive television systems will probably come sooner--and promise an even more profound change in viewing habits. Not only will there be a vast expansion of programming choices--customers will be able to select from hundreds of movies in an electronic library, for example--but interactive TV will also allow people to play video games with their friends, see and order the latest clothing from a department store and even edit their own evening news programs.

Indeed, the installation of two-way digital transmission systems on cable television networks will create an entirely new type of communications system. By the end of the decade, it may be economical for consumers to set up a high-quality “videophone” link with a neighbor, print out a newspaper that’s sent electronically or help edit a document on a computer thousands of miles away.

“Interactive TV will mostly be things that haven’t even been dreamed up yet,” says Tom Adams, an analyst with the media research firm Paul Kagan & Assoc. “But the ability to interact with your TV is so compelling that applications are bound to come along.”

What’s Coming

High-Powered Satellite--Sends signals to small, cheap dishes.

Video Compression--Allows a single satellite channel to carry up to two dozen TV programs, reducing costs.

High Definition--Brings cinema-quality pictures to wall-mounted, flat-panel TVs.

Interactive TV--Allows viewers to play video games with friends, order products from stores or edit news programs, among other options.