digitaltv

How is TV signal transmitted? A technical overview

  • Digital TV, depending on the way to transmit signals, can be divided into terrestrial, satellite and cable TV, on the one hand, and those delivered through the Internet protocol suite (IPTV, OTT), on the other hand.
  • Each way of signal transmission has its own standards. The mostly widespread ones are DVB standards (Digital Video Broadcasting).
    • DVB-T and DVB-T2 (Т – Terrestrial) standards correspond to terrestrial television. GS Group One TV project in Cambodia operates on DVB-T.
    • DVB-S and DVB-S 2 (S – Satellite) standards correspond to satellite television. Examples:  Tricolor TV, BSkyB and DishNetwork.
    • DVB-C and DVB-C2 (C – Cable) are cable television standards.
  • Satellite television:
    • The key device in the satellite TV networks the transponder. Transponders are placed on satellites and serve for transmission of signals from terrestrial stations of TV operators to the TV equipment of subscribers (up and down links).
    • It is possible to place on some satellites up to 70 transponders in different frequency bands.
    • The main characteristic of transponders is the band width measured in MHz. The larger it is the more TV channels it is possible to transmit.
    • An average cost of a MHz is about 30 000 USD/year. Depending on the region this figure can vary by several times.
    • A transponder with a 36 MHz band width can transmit on average 20-25 SD channels and 5-6 HD channels.
    • SD (standard definition) is a system based on analogue signals that appeared in 1940s. (PAL, SECAM, NTSC). With a relatively law resolution, pictures transmitted need a small band width.
    • HD (high definition) owes its standards to the digital TV. An HD broadcast image is approximately 5 times more accurate than an SD image. However, such a detalization needs a larger band width.
    • SES, EUTELSAT and GazKom are amongst the largest European satellite operators.


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Comments 2

I am interested about digital tv system. want know more update news about Gs beximco dth in bangladesh.

Ekaterina Tyukel
Ekaterina Tyukel Admin / 12.12.2014 at 17:27

Dear Zaman, thank you for your question and interest to the GS Group projects. As you know, GS Group and Bangladesh-based industrial conglomerate, Beximco Group have jointly set up a DTH company, Beximco Communications Limited, and intend to launch a DTH platform in Bangladesh during the first half of 2015. We hope to share the news on the project early in the incoming year. We will keep on posting on the digital television issues so please follow our blog to keep up with the key industry trends!