CTCS Balise’s Signals And Telegrams Detector

In recent years, there is a challenge on reliability of data transmission between theOn_board Transmission Equipment and the Balise, while high-speed railway isdeveloping rapidly in China. As a key subsystem, the Balise Transmission System’ssignals and telegrams have been defined in relevant Norms. At present, detection of ‘C’interface’s signals has not been paid much attention to, detection of Balise is mainlyabout its telegrams. CTCS Balise’s signals and telegrams Detector is composed of frontdetecting circuits, MCU and peripheral circuits and user application software on PC.Beside detecting telegrams, it is also designed for detecting the ‘C’ interface’s signals.Research and design of the Detector make great sense in ensuring the safety of railwaysand trains.This thesis is mainly on the research and design of front detecting circuits,including the following contents:1. Research on detection of ‘C’ interface’s signals: Analyze characteristics of ‘C’interface’s signals, propose detecting scheme which includes signal conditioning circuit,DBPL signal decoding circuit and PLL circuit. Input signal will be attenuated, separated,shaped, and then get the sine wave’s frequency and amplitude and DBPL signal’sfrequency and amplitude. Analyze DBPL signal’s coding principle, complete the designof DBPL signal’s decoding circuit. Study on the theory of PLL and implement the PLLcircuit’s design.2. Research on detection of ‘A’ interface’s signals: Analyze ‘A’ interface’s signals’transmitting mode, circuit’s design scheme is proposed, complete antenna and poweramplifier’s analysis of theory and simulation. Besides, circuit’s stability and impedancematching circuit are also optimized.3. Design of anti-jamming: Three methods have been taken to promote circuits’ability of anti-jamming. Firstly, choose low-noise and suitable bandwidth components.Secondly, improve methods of circuits’ design. Thirdly, filtering and grounding is alsoused in circuits.4. Data processing and error analysis: Test plan, test environment and test tools are introduced, study on the theory of error and list square fit, and ‘C’ interface’s signaldetecting circuits’ indicators are tested and analyzed.