BBC R&I demonstrates Freeview HD
After theThe "secret" Ofcom plan for Freeview HDTV: DVB-T2 - ukfree.tv - independent digital television and switchover advice, since 2002 , and then DVB-T2 update - ukfree.tv - independent digital television and switchover advice, since 2002 and finally the test transmissions starting BBC starts Freeview HD test in Guildford - ukfree.tv - independent digital television and switchover advice, since 2002, the BBC's Research and Innovation department have finally demonstrated the service working for real.
Freeview HD, which will provide three channels at 1280 samples x 720 lines per frame (2.25 times standard definition), uses the new DVB-T2 standard which, after approval on 26 June 2008, started the world's first transmissions from the Guildford transmitter the following day.
Friday 29th August saw engineers demonstrate for the first time a working receiver capable of displaying the transmissions on a high definition television set.
ustin Mitchell, leader of the DVB-T2 modem development team at the BBC, said: "Following the approval of DVB-T2 in June and the launch of test transmissions from Guildford transmitter the next day, we are delighted that on Kingswood Warren's 60th anniversary our team has been able to deliver a working demonstration of a DVB-T2 modulator and demodulator."
There will be a demonstration of the DVB-T2 modulator and demodulator on the DVB stand 1.D81 at the International Broadcasting Convention in Amsterdam in September 2008, along with hourly talks and conference papers.
However, the service will be inferior to that provided already on Freesat, where each frame is 1920 samples on 1080 lines (5 times standard definition).
Both the modulator and demodulator are available for licensing to third parties from the BBC.
The working specification, as reported before is three MPEG-4 services on a multiplex providing 36 megabits per second. It uses 32,000 fast Fourier transformations, a 1/128 microsecond guard interval, LDPC (in 64,800 blocks) and BCH (3/5) error correction.
The transmission is in a 16x16 (256) quadrature amplitude modulation constellation
See also A comparison of TV, HDTV and computer monitors - ukfree.tv - independent digital television and switchover advice, since 2002
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