The time is ticking - on February 17, 2009 the TV transmission in US is going to change from Analog to Digital. Congress has already passed legislation requiring all conventional analog TV broadcasting to stop on February 17, 2009. After that date the television broadcasters will be making only Digital TV broadcasts. In general terms digital TV signals are sent from the transmitters over the air, to homes, by modern digital techniques rather than the older analog methods that are not as efficient as the digital signals.
TV broadcasts have used the technology invented in the 1920's and 1930's till date. Color was added in the 1950's, but the technology was same. Digital television is actually the transmission of television signals using digital methods. Analog transmission is always as a constantly variable wave; digital transmission consists of an electrical pulse which has two possibilities: on and off, which are represented by a one and a zero. Because a digital signal does not fluctuate, it is either present or totally absent, a digital transmission is more precise than an analog transmission. Although, both signals are transmitted in same way and have the same range, but they behave differently at the limits of their ranges. An analog signal degrades over distance and may be barely detectable at the farther reaches of the broadcast area. As the signal reaches the farther limits of its range, the signal-to-noise ratio decreases and the quality of the broadcast suffers, although the range remains the same. In comparison, when the signal-to-noise ratio decreases in a digital signal, the quality of the broadcast does not degrade, but the range shrinks.
There are many advantages of DTV over Analog TV some of them are superior image resolutions for a given bandwidth, smaller bandwidth for a given image resolution, compatibility with computers and the Internet, interactivity, superior audio quality, consistency of reception over varying distances, capacity for multicasts etc. These features place the DTV much ahead of Analog TV and future of DTV looks very bright.
In the future, cable operators might also move to all digital means of delivery, which means you may be required to lease a set-top box or own a TV with a digital cable tuner to continue to receive the channels you now view on a conventional TV.
The transition from analog to digital TV is not going to affect the future of the commercial video equipments like DVD players or other video equipments. Future of the videos produced for the computers and Internet are poised for a big leap ahead. The DTV equipped with enhanced video quality, increased resolution handling and compatibility with computers would pave the way for thousands of beautiful amateur videos currently unavailable for the general masses. High quality videos currently available on the net would be shared and shown to the masses through DTV soon without compromising on their quality of the video. The future of video seems to be on the launch pad of a very bright path with DTV.