Terrestrial digital TV transmission standard DTMB evolution system
Author： Source：dtvnel Time：2014-02-20 18:42:04 Number：
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DTMB international standard possesses advanced technology, complete property right, advanced performance, and has a widespread deployment. A industrial standard system integrating the DTMB, E-DTMB, and DTMB-A has already been constructed. Among them, DTMB is used for the public broadcasting network; E-DTMB will play a more important role in mobile reception and data broadcasting; DTMB-A is suitable for multi integrated services of higher quality.
Compared to DVB-T system, DTMB has more powerful system performance, larger information capacity, higher mobile indexes, and broader broadcasting coverage. The DTMB system not only has the congenital superiority in terms of system design, technical performance and so on, but also has a strong international competition ability in equipment costs. This is mainly due to: 1) DTMB’s original TDS-OFDM system, leading to the superiority in signal spectrum efficiency, processing speed, anti-interference and complete intellectual property coverage; 2) firstly adopting the LDPC code, that allows the signal receiving threshold maintaining comparative advantages; 3) adopting the time-frequency domain processing technology, thus creating the characteristics in dynamic channel allocation, and mobile reception, which is more convenient for multi-service broadcast.
The E-DTMB system is fully compatible with DTMB. It could realize a variety of modulation modes in the same TV channel; it supports 330 patterns regulated by DTMB; using the digital resampling, it supports 6, 7 or 8MHz bandwidth mode, and supports the transmission embedded multi-service (which cannot be realized by the first generation of international standard ).
The DTMB-A system is a evolution scheme of DTMB system. Its overall performance reaches or exceeds DVB-T2, for examples: adding 256APSK and higher order FFT options, which enables the transmission rate is higher than that of DVB-T2; using Gray-APSK modulation and the new LDPC code, with a receiving C/N threshold lower than DVB-T2; new multiframe signaling structure and time-frequency two-dimensional dynamic allocation supporting the multi-service simulcasting more conveniently; the multi-antenna technique based on time frequency synthesis, supporting more complex enhanced single frequency network, etc.
What are mainly presented here are the application demonstration system of DTMB international standard and its evolution standard and the achievements of related products.
Terrestrial digital TV transmission standard DTMB evolution system - System display -
Natlonal EngLneering Leb.For CTV(Beijing)
Actually Pakistan first HD channel was lanched couple of months ago.
92 News: Pakistan's First HD Channel Is Here :
