Latest Technology in ICT – Switch to Digital Televison

Digital television (DTV) is the sending and receiving of moving images and sound by discrete (digital) signals, in contrast to the analog signals used by analog TV.

As of late 2007, 7 countries had completed the process of turning off analog terrestrial broadcasting. Many other countries had plans to do so or were in the process of a staged conversion. The first country to make a wholesale switch to digital over-the-air (terrestrial) broadcasting was Luxembourg, in 2006, followed by the Netherlands later in 2006, Finland, Andorra, Sweden, Norway and Switzerland in 2007, Belgium (Flanders) and Germany in 2008, and the United States in 2009.

In the United States, high-power over-the-air broadcasts are solely in the ATSC digital format since June 12, 2009, the date that the FCC set for the end of all high-power analog TV transmissions. As a result, almost two million households could no longer watch TV because they were not prepared for the transition. The switchover was originally scheduled for February 17, 2009 until the US Congress passed the DTC Delay Actt. By special dispensation, some analog TV signals ceased on the original date.

In Japan, the switch to digital is scheduled to happen July 24, 2011. In Canada, it is scheduled to happen August 31, 2011. China is scheduled to switch in 2015. In the United Kingdom, the digital switchover has different times for each part of the country; however, the whole of the UK will be digital by 2012. Brazil switched to digital on December 2, 2007 in major cities and it is estimated it will take seven years for complete signal expansion over all of the Brazilian territory.

In Malaysia, the Malaysian Communications & Multimedia Commission (MCMC) will call for tender bids in the third quarter of 2009 for the UHF 470–742 megahertz spectrum which will pave the way for the country to move into the digital television era. The awarding of the spectrum will see the winner having to build a single digital terrestrial transmission/TV broadcast (DTTB) infrastructure for all broadcasters to ride on to transmit their TV programs. The winner will be announced at the end of 2009 or early 2010 and has to commence digital roll-out soon after the award where the analog switch-off is planned for 2015.

DTV has several advantages over analog TV, the most significant being that digital channels take up less bandwidth (and the bandwidth needs are continuously variable, at a corresponding reduction in image quality depending on the level of compression as well as the resolution of the transmitted image). This means that digital broadcasters can provide more digital channels in the same space, provide high-definition television service, or provide other non-television services such as multimedia or interactivity. DTV also permits special services such as multiplexing (more than one program on the same channel), electronic program guides and additional languages, spoken or subtitled. The sale of non-television services may provide an additional revenue source.

Digital signals react differently to interference than analog signals. For example, common problems with analog television include ghosting of images, noise from weak signals, and many other potential problems which degrade the quality of the image and sound, although the program material may still be watchable. Digitized signals are designed to resist ghosting or noise by using a redundant signal composed of numeric codes. Even if some of the information is missing or wrong, the decoder computer can reconstruct the complete signal. The only way it fails is when the decoder does not receive enough information from the antenna — if there is too much interference in the signal for the decoder to read enough of the numbers and produce the picture. This can render a digital signal completely or partially unwatchable (picture pixelates or freezes) in situation where an analog signal would still be usable, in urban (ghosting due to multi-path) and rural (weak signal) areas.

Therefore, it is the time for us to digitalize our television due to its benefits. So why not we make an investment in buying the devices before the analog based completely switched off at 2015. Let’s us wait for its arrival…

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