Hardware Implementation And Coverage Testing On The Railway Television Single Frequency Network System

Chinese railway is experiencing dramatic development. In recent years, the Chinese government has committed massive investment in railway system, particularly the construction of high-speed passenger-only line. According to a survey, railway television is the most popular service the travelers expect to see. Therefore, it can be predicted that the railway television broadcasting technology will enjoy large-scale application in the next few years.Railway TV can be broadcasted via a single frequency network technology. Compared with traditional multi-frequency network, SFN has the advantages of saving spectrum resources, facilitating spectrum planning and so on. Therefore, railway TV combining the digital television broadcasting technology with single frequency network, could solve the coverage of railway SFN and transmission in high-speed movement environment, will have great potential for deployment and application.ADTB-R is a single frequency network television technology suitable for the railway system, and this is also the focus of this paper. Through the analysis of key technologies and system architecture in single frequency network rail TV, we first design the kernel modules which contain the adaptive module, the synchronous modulation module, the diversity receiver module and so on. Then we combine the kernel modules and the other modules to build the all the independent equipments of railway TV SFN system. These equipments include satellite adapter, terrestrial synchronous modulation transmitter and vehicle-mounted diversity receiver. Finally, these devices are formed a complete SFN system to do the experimental section of Shanghai to Wuxi railway television.Through several times of the experimental section of Shanghai to Wuxi railway television, we have got complete test data. After summarize the trial data, we found that two-directional antenna diversity reception technology could simplify the channel model which the railway television faces; the open-loop self-healing mechanisms could ensure reliable synchronization of the SFN system. Ultimately,we got the conclusion that the Single Frequency Network Railway TV based on the technology of ADTB-R is very suitable for the particular application of China Railway Television.