System Differences With DVB-T
The following table reports a comparison of available modes in DVB-T and DVB-T2.
| DVB-T | DVB-T2 | |
|---|---|---|
| Input Interface | Single Transport Stream (TS) | Multiple Transport Stream and Generic Stream Encapsulation (GSE) |
| Modes | Constant Coding & Modulation | Variable Coding & Modulation |
| Forward Error Correction (FEC) | Convolutional Coding + Reed Solomon 1/2, 2/3, 3/4, 5/6, 7/8 | LDPC + BCH 1/2, 3/5, 2/3, 3/4, 4/5, 5/6 |
| Modulation | OFDM | OFDM |
| Modulation Schemes | QPSK, 16QAM, 64QAM | QPSK, 16QAM, 64QAM, 256QAM |
| Guard Interval | 1/4, 1/8, 1/16, 1/32 | 1/4, 19/256, 1/8, 19/128, 1/16, 1/32, 1/128 |
| Discrete Fourier transform (DFT) size | 2k, 8k | 1k, 2k, 4k, 8k, 16k, 32k |
| Scattered Pilots | 8% of total | 1%, 2%, 4%, 8% of total |
| Continual Pilots | 2.6% of total | 0.35% of total |
For instance, a UK MFN DVB-T profile (64-QAM, 2k mode, coding rate 2/3, guard interval 1/32) and a DVB-T2 equivalent (256-QAM, 32k, coding rate 3/5, guard interval 1/128) allows for an increase in bit rate from 24.13 Mbit/s to 35.4 Mbit/s (+46.5%). Another example, for an Italian SFN DVB-T profile (64-QAM, 8k, coding rate 2/3, guard interval 1/4) and a DVB-T2 equivalent (256-QAM, 32k, coding rate 3/5, guard interval 1/16), achieves an increase in bit rate from 19.91 Mbit/s to 33.3 Mbit/s (+67%).
Recommended maximum bit-rate configurations for 8 MHz bandwidth, 32K FFT, guard interval 1/128, pilot pattern 7:
| Modulation | Code rate | Bitrate Mbit/s | Frame length LF | FEC blocks per frame |
|---|---|---|---|---|
| QPSK | 1/2 | 7.4442731 | 60 | 50 |
| 3/5 | 8.9457325 | |||
| 2/3 | 9.9541201 | |||
| 3/4 | 11.197922 | |||
| 4/5 | 11.948651 | |||
| 5/6 | 12.456553 | |||
| 16-QAM | 1/2 | 15.037432 | 60 | 101 |
| 3/5 | 18.07038 | |||
| 2/3 | 20.107323 | |||
| 3/4 | 22.619802 | |||
| 4/5 | 24.136276 | |||
| 5/6 | 25.162236 | |||
| 64-QAM | 1/2 | 22.481705 | 60 | 151 |
| 3/5 | 27.016112 | |||
| 2/3 | 30.061443 | |||
| 3/4 | 33.817724 | |||
| 4/5 | 36.084927 | |||
| 5/6 | 37.618789 | |||
| 256-QAM | 1/2 | 30.074863 | 60 | 202 |
| 3/5 | 36.140759 | |||
| 2/3 | 40.214645 | |||
| 3/4 | 45.239604 | |||
| 4/5 | 48.272552 | |||
| 5/6 | 50.324472 |
Read more about this topic: DVB-T2
Famous quotes containing the words system and/or differences:
“Short of a wholesale reform of college athletics—a complete breakdown of the whole system that is now focused on money and power—the women’s programs are just as doomed as the men’s are to move further and further away from the academic mission of their colleges.... We have to decide if that’s the kind of success for women’s sports that we want.”
—Christine H. B. Grant, U.S. university athletic director. As quoted in the Chronicle of Higher Education, p. A42 (May 12, 1993)
“Traveling, you realize that differences are lost: each city takes to resembling all cities, places exchange their form, order, distances, a shapeless dust cloud invades the continents.”
—Italo Calvino (1923–1985)