The Standard
The following characteristics have been devised for the T2 standard:
- COFDM modulation with QPSK, 16-QAM, 64-QAM, or 256-QAM constellations.
- OFDM modes are 1k, 2k, 4k, 8k, 16k, and 32k. The symbol length for 32k mode is about 4 ms.
- Guard intervals are 1/128, 1/32, 1/16, 19/256, 1/8, 19/128, and 1/4. (For 32k mode, the maximum is 1/8.)
- FEC is concatenated LDPC and BCH codes (as in DVB-S2 and DVB-C2), with rates 1/2, 3/5, 2/3, 3/4, 4/5, and 5/6.
- There are fewer pilots, in 8 different pilot-patterns, and equalization can be based also on the RAI CD3 system.
- In the 32k mode, a larger part of the standard 8 MHz channel can be used, adding about 2% extra capacity.
- DVB-T2 is specified for 1.7, 5, 6, 7, 8, and 10 MHz channel bandwidth.
- MISO (Multiple-Input Single-Output) may be used (Alamouti scheme), but MIMO will not be used. Diversity receivers can be used (as they are with DVB-T).
- Multiple PLP to enable service specific robustness.
- Bundling of more channels into a SuperMUX (called TFS) is not in the standard, but may be added later.
Read more about this topic: DVB-T2
Famous quotes containing the word standard:
“The art of advertisement, after the American manner, has introduced into all our life such a lavish use of superlatives, that no standard of value whatever is intact.”
—Wyndham Lewis (1882–1957)
“There is a certain standard of grace and beauty which consists in a certain relation between our nature, such as it is, weak or strong, and the thing which pleases us. Whatever is formed according to this standard pleases us, be it house, song, discourse, verse, prose, woman, birds, rivers, trees, room, dress, and so on. Whatever is not made according to this standard displeases those who have good taste.”
—Blaise Pascal (1623–1662)