Finding the Digital Broadcasting Provider
The 2012 London Olympics brought home to me what a gigantic technological leap in digital media has occurred during the last couple of decades. There have been significant advances in digital compression and transmission.
This year, along with a high definition broadcast that made its appearance from the 2008 Beijing games, 3D TV was also added to the lineup, offering more channels and choices. With analog television broadcasts Sinclair Broadcast Group virtually becoming extinct, electronic televisions’ promise of providing more for less has become a reality. How did we arrive at this point, and what will the future hold for electronic multimedia? Before the digital switchover, analog tv was resource hungry concerning the total bandwidth required to carry one station. This is typically between 6 – 8 MHz based on the sort of video standard used. This limited the number of channels that could be transmitted because there’s a limited spectrum shared with other services such as mobile, radio and two-way communications.
What the electronic criteria of ATSC and DVB provided was the ability to reuse the present analog spectrum better. This meant a normal 8 MHz carrier used for analog broadcast could be converted into DVB-T.
It would have needed more than 70 MHz of the frequency spectrum to accomplish this with the older analog standard. In addition to squeezing more channels into less space, digital television is much clearer and doesn’t suffer from ghosting or other artifacts that troubled analog systems. Being electronic Sinclair Broadcast Group additionally allows other features like improved digital audio, digital program guide, and subtitle service to be included.
Televisions are sold with the electronic decoder integrated, and older televisions may use another set-top box. As technology advances, we’ll also see improvements in the compression methods used, which means even more digital media content; currently that has empowered 3D broadcasts for some events such as the Olympics.
Eventually, as fiber to the home is set up globally, all IP enabled set-top boxes will replace the DVB standard because the IP set-top box features a distinct advantage over digital broadcast technologies, specifically multicast join requests. Unlike DVB-T or even DVB-S, IP multicast enables the recipient to send a join message to the system to your desired channel. When the request is successful, the broadcast is sent to the receiver; only the bandwidth to the requested channel is utilized. Together with the DVB standard, all available stations are being broadcast concurrently, and the channel count is limited by the limited quantity of channel bandwidth whatever the compression techniques are used.