• A delegation from Timor Leste visit DTVNEL(Beijing)
  • DTVNEL held successfully International DTV Forum in Lao
  • Sharing of test platform is established in DTVNEL
  • DTVNEL attended the 4th China-Africa media cooperation forum
  • DTMB technology training course is held for Pakistani delegation
  • Pakistani delegation visited DTVNEL again

DTMB-A transmission system

In February, 2012, DTVNEL(Beijing) had a major breakthrough for DTMB-A standard research and development. There were 5 significant improvements on that core technologies:

1) Add parameters “256 APSK and FFT” to increase the maximum transmission bandwidth to 50.7Mb/s, which has exceeding European 2nd-generation DTV standard “DVB-T2” and approximately 50% higher than DTMB standard. It’s easily to meet various broadcasting service.
2) C/N threshold of reception is better than DVB-T2 standard cause of using Gray-APSK constellation and the latest LDPC code, compatible with multiple code rate (1/2, 2/3, 5/6) and multiple code length (15360, 61440) meantime.
3) Uses the latest multiplex frame structure and two-dimensional dynamic allocation for the clock and frequency.
4) Uses TDS-OFDM antenna diversity technology for reducing the difficulties to set up single frequency network (SFN).
5) Peak-average power ratio(PAPR) reduction by a special extension of constellation.

A simulation was implemented by FPGA and computer after system design, the feature “C/N threshold” of proto is nearly 1 dB advantage than using a DVB-T2 set top for reception test, DTMB-A standard is also 0.7 dB gain advantage at a performance test for different channel diversity scheme.

After all, DTMB-A Standard depends on careful design and inherit existing advantages from DTMB standard to exceed the other latestinternational DTV standards.