Believe It or Not You Have a Bright Future of Digital TV in the Internet Age

Around the theme of “Innovation and Public Services for Fusion”, the conference invited Mr. Huang Xiaobing, Director of the Radio Administration Bureau of the State Administration of Radio, Film and Television, Mr. Zou Feng, Director of the Academy of Broadcasting Science and Technology of the State Administration of Press, Publication, Radio, Film and Television, and Director of the Zhongguancun Digital TV Industry Alliance. Chang Yang Zhixing and the State Bureau of Press, Publication, Radio, Film and Television, Academy of Broadcasting Sciences, Beijing Tongfang Jizhao Technology Co., Ltd., Guangzhou Guanghan Digital Technology Co., Ltd., Suzhou Quanbo Communication Technology Co., Ltd., Chengdu Dexin Digital Technology Co., Ltd., Chengdu Kai Teng Sifang Digital Broadcasting & TV Equipment Co., Ltd., Shanghai Oriental Pearl Digital TV Co., Ltd., Guilin Siqi Communication Equipment Co., Ltd. and other relevant leaders and industry experts, well-known corporate experts, for the integration of the media era of radio and television innovation, triple play Developed digital terrestrial television and delivered special lectures. He exchanged views on new developments in the field of converged networks and terrestrial digital television, related policies, technological innovations, new business development, and application achievements, with a view to advancing digital television in China. Industry across the development process.


The author's greatest experience with this conference is that the development prospects of domestic digital television are broad.

China’s terrestrial digital television has gone through nearly 20 years since it started research. It has gone through standard research, drafting, perfection, promulgation, promotion, promotion and application. Today, China’s terrestrial television has entered an important period of comprehensive analog-to-digital conversion. Reviewing the development history of digital terrestrial television in China, both experience and lessons have been learned, and it is also recognized that terrestrial digital television in China has broad prospects for development.

After decades of development, China has gradually established a comprehensive coverage network of radio and television coverage nationwide that combines terrestrial television, cable television, and direct broadcast satellites. Among them, terrestrial television broadcasting, which is an important component of the national public cultural service system, especially in rural areas where cable television cannot reach, has become the most important information channel for local residents. It is the local government that provides basic public broadcasting for the general public. The main means of service.

According to statistics, at the beginning of 2014, China’s total population was 1.36 billion, of which: rural population was 630 million, and 210 million households. The cumulative number of households in the country exceeded 430 million. Up to now, the number of cable television subscribers in China has reached 224.9 million, of which there are 172 million cable digital television users; the total number of public service users of direct-viewing satellites in China has exceeded 37.84 million.

It can be seen that there are still nearly 200 million rural household users in China unable to enjoy rich-content radio and television public services. The report of the 18th CPC National Congress clearly stated that "Let the rural people enjoy the equalization of basic public services."

Therefore, in China, the development of terrestrial television, especially the development of digital terrestrial television is particularly important. On the one hand, terrestrial digital television can be a useful complement to cable digital television in cities; on the other hand, terrestrial digital television can also provide cooperative coverage with direct broadcast satellites in rural areas to provide rural household users with high-quality broadcast and television public services.

After years of development, especially since 2006, China’s terrestrial digital television broadcasting has made great progress. The upstream and downstream industrial chain of digital terrestrial television has become very sophisticated and mature, and the potential user market for digital terrestrial television in China is very large.

At present, China is in the period of terrestrial television transition from analog to digital. The closure of terrestrial analog TVs is a long way to go, especially in the next 5 to 10 years, which is a key stage for the development of digital terrestrial television in China. At the same time, research on a new generation of digital terrestrial television standards is underway in the world. The European DVB-T2 standard has been formally promulgated, and the United States is stepping up efforts to develop the ATSC 3.0 standard. Therefore, for the future development of digital terrestrial television in China, comprehensive consideration should be given from the perspective of industry promotion policy and technology.

In order to further promote the rapid development of China’s terrestrial digital television industry and promote the healthy and sustainable development of terrestrial digital TV in China, since 2012, the State Administration of Press, Publication, Radio, Film and Television, and the Ministry of Industry and Information Technology have successively formulated and introduced a number of terrestrial digital television developments. policy.

In December 2012, the State Administration of Radio, Film and Television formally released the “Development Plan for Terrestrial Digital TV Broadcast Overlay Network” (GF [2012] No. 113). According to the plan, by 2020, the nationwide terrestrial digital television broadcasting coverage network will be basically completed, providing the first and seventh sets of CCTV and the first set of local TV programs, such as HD and SD public service programs, and terrestrial digital television. The overall coverage rate basically reaches the current level of analog TV coverage. Terrestrial digital television receivers are basically universal. More central, provincial, local agricultural science and education television programs, and other ethnic minority language television programs have entered the terrestrial channel through HD and SD. For the majority of the people in urban and rural areas to provide a number of high-quality programs, radio and television public service has been greatly improved.

In 2020, terrestrial analog television signals will stop broadcasting, and terrestrial television will achieve a strategic transformation from analog to digital. In January 2013, the six ministries and commissions including the National Development and Reform Commission of the State Ministry of Industry and Information Technology and the State Administration of Radio, Film and Television issued the “Implementation Opinions on the Popularization of Terrestrial Digital Television Receivers” (Ministry of Industry and Information Technology Co., Ltd. [2013] No. 14), and formally confirmed that all televisions sold in China are It should have terrestrial digital television reception capabilities, meet the national standards for terrestrial digital television receivers, and publish a timetable for specific implementation.

The first generation of terrestrial digital television standards in the world has been promulgated for nearly 20 years. Based on the first generation of terrestrial digital television transmission standards, countries around the world have successively carried out and completed digitized digital terrestrial television conversions. At the same time, research and improvement are being carried out internationally in response to the problems and deficiencies in the first generation of terrestrial digital television standards.

Since 2000, the European Digital Video Alliance (DVB) has sought to find ways to increase the data rate of DVB-T terrestrial digital television transmissions while improving the stability and flexibility of the transmission network.

A major improvement in the DVB-T2 standard formally promulgated in 2009 was the adoption of the concept of physical layer pipes, support for multi-service functions, and the expansion of service types from a single TS stream to multiple types (eg, generic streams, IP flows, etc.) );

Adopt more advanced channel coding and more flexible framing to improve network throughput (50% increase in system capacity), spectrum utilization, and anti-jamming capability;

Adopt optional transmit diversity mechanism based on Alamouti code, support MISO, use more carrier modes and guard interval options, support wider range of single frequency network (more than 200km protection interval), expand network coverage, reduce network formation And maintenance costs.

In addition, DVB-T2 also considered support for mobile TV services and developed the DVB-T2 Lite solution, which is designed for economical mobile devices and allows broadcasters to use the existing DVB-T2 transmission equipment for mobile services. At the same time, the DVB organization is also studying the more complex mobile reception standard DVB-T2 NGH, which is not only compatible with T2 Lite, but also supports MIMO and terrestrial satellite hybrid reception.

In the United States, ATSC, the first-generation terrestrial digital television system, has already started the evolution and evolution after experiencing a less successful intermediate version of ATSC-MH. It has begun to evolve the ATSC system to the next generation, with high spectrum efficiency and multi-service support capabilities. Is the focus of its evolution process. To this end, ATSC has accelerated research and standards development for the next generation of digital television systems in the United States. In March 2013, ATSC formally announced to the world an announcement for the acquisition of the next generation digital television system (ATSC3.0) physical layer solution. ATSC requires that the new system be able to give full play to the advantage of broadcasting one-to-many and effectively distribute popular content to a wide range of users; the new system requires further enhancement of transmission performance, support for the transmission of future ultra high-definition television, support for multiple service terminals and new types. The flexible application of services; the new system should consider adopting an international core technology.

In Japan, the NHK Institute has reformed and optimized terrestrial digital TV HDTV ground fixation and mobile reception technologies.

In terms of fixed reception. Japan has incorporated new technologies into existing standards such as super-multilayer OFDM modulation, high-order QAM modulation (currently 4096QAM is possible), dual-polarized multiple-input multiple-output (MIMO) technology at the transmitter and receiver, Combine MIMO channel estimation and prediction to improve the receiving performance of the system. In terms of mobile reception, spatial frequency block coding (SFBC) technology is used to obtain additional spatial diversity gain, thereby enhancing the robustness of wireless broadcast signal transmission. Overall, the evolution of the ISDB-T system in Japan is still in the technological research stage, and it does not really initiate the process of standardization and industrialization.

In China, while the first-generation terrestrial digital TV DTMB has been popularized, the major research institutions in China have closely followed the development trend of international digital terrestrial television and are committed to the exploration and research of a new generation of terrestrial digital TV technology in China.

Regardless of whether it is international or domestic, the evolution direction of terrestrial digital television technology is the same, that is, it supports higher channel transmission capacity, has stronger anti-jamming capability, supports more flexible service types, and expands terrestrial digital television network two-way interactive capabilities and improves. Terrestrial digital television network business carrying capacity, innovative value-added business forms, and further enhance the user experience.

After the development in recent years, especially since 2006, China’s terrestrial digital television broadcasting has made great progress. The upstream and downstream industry chain of digital terrestrial television has been very sophisticated and mature, and the potential user market for digital terrestrial television in China is very large.