Here’s another series blog post. This time its about Digital Television. Not many know or even cares about Digital TV although they are using it.
I’m not that familliar with DTV so I would also like to know more about it. So, lets learn together. Let’s learn what Digital TV (DTV) is. What DTV standards are present and how DTV can improve our lives. I hope I’ll lay down the facts as simple as possible.
Digital television (DTV) is the sending and receiving of moving images and sound by digital signals, in contrast to the analog signals used by analog TV. – (Wikipedia) We won’t talk about the old Analog TV here. Without going too technical about it, DTV brings better viewing pleasure to the users. Its more advanced than Analog TV (not to be confused between colored and Black and white TV).
Now there are many ways of bringing Digital TV to the users.. either through satellite, cable, microwave frequency (but is mostly used from internet connection), or terrestrial (terrestrial a term which refers to modes of television broadcasting which do not involve satellite transmission – errr…. through the use of antena). If that confused you, just think that the use of Satellite and Cable are offered for a fee. While terrestrial transmissions are mostly free – and with the use of an antena.
The United States have already switched to Digital TV. Why?
[US] Congress mandated the conversion to all-digital television broadcasting, also known as the digital television (DTV) transition, because all-digital broadcasting will free up frequencies for public safety communications (such as police, fire, and emergency rescue). Also, digital is a more efficient transmission technology that allows broadcast stations to offer improved picture and sound quality, as well as offer more programming options for consumers through multiple broadcast streams (multicasting). In addition, some of the freed up frequencies will be used for advanced commercial wireless services for consumers. – FCC
Other countries are reported to cut do the analog “switc-off” on the following dates:
- August 31, 2011 in Canada,
- July 24, 2011 in Japan
- 2012 in the United Kingdom,
- October 14, 2009 in some regions of North-Italy
- December 31, 2015 in the Philippines
There are different formats of Digital TV. Two of the most widely known DTV formats are High-definition television (HDTV) and Standard definition TV (SDTV). These formats varry from the manner they are sent to users, the scale size, quality, compression rates, etc.
So there are different ways of sending different formats of Digital TV. Naturally, there will also be different ways of receiving Digital TV. You can receive Digital TV on your:
- Television sets
- Mobile Phones
- Internet Protocol Television (IPTV) – using the internet to watch TV
If you have an analog TV set and wants to get Digital TV signal, then you need DTV converter boxes. Some mobile phones can now get DTV signals via mobile DTV standards such as DVB-H. And a lot of netizens now can watch TV via the internet using IPTV.
How Stuff Works provides a good explanation of how DTV works:
Each broadcaster has one digital TV channel, but one channel can carry multiple sub-channels if the broadcaster chooses that option. Here’s how it works:
On its digital channel, each broadcaster sends a 19.39-megabit-per-second (Mbps) stream of digital data. Broadcasters have the ability to use this stream in several different ways. For example:
> A broadcaster can send a single program at 19.39 Mbps.
> A broadcaster can divide the channel into several different streams (perhaps four streams of 4.85 Mbps each). These streams are called sub-channels. For example, if the digital TV channel is channel 53, then 53.1, 53.2 and 53.3 could be three sub-channels on that channel. Each sub-channel can carry a different program.
On my next posts, we’ll get to know more about DTV for Television, DTV for Mobile Phones and DTV for internet addicts like me.
- Digital TV on Mobile Phones
- Latest in Digital TV in the Philippines
- Digital TV in the Philippines
- Let’s Go Digital TV