Design And Implementation Of The Control System Of Search And Rescue Radar Transponder

Search and rescue radar transponders (SART) is an important equipment in theGlobal Maritime Distress and Safety System (GMDSS) which is used to alert thedistress and instruct the location of the distressing ships. It is installed on the lifeboatsor be carried by drowning person. Once encountering danger, person on the ship canmake it work, or it can self-start work. When receiving rescue signals emitted by theX-band navigation radar on the aircraft, it enters into the working status, and instantlyresponds echo signal to the rescue radar of which the screen will display the exactposition of the distressing vessel. As a result, the SART not only shortens the rescuetime but also reduces the property damage and casualties caused by the accident. Atpresent, the development of SART in China is in the backward status compared toEurope, the U.S, Japan and South Korea. Therefore, it is of great significance to studydesigning SART.The main contents are as follows:1. Introducing the SART’s role as well as its basic principle. Then it studied out theoverall design of SART system according to the technical specifications. SART ismainly composed of antenna, circulators, transceiver and control system.2.Designing the control system. The development of the entire control system isbased on complex programmable logic device(CPLD). CPLD has lots of advantages ashigh-performance, low-cost, low-power and easy to expand.3.According to IEC1097-1and Taking a consideration about low powerconsideration, I analysis and determine the circuit timing of low-noise amplifier (LNA),voltage-controlled oscillator (VCO) and power amplifier transceiver. I also design andsimulate the shaping circuit, the integrating circuit and the power supply circuit. Theradar signal received by the antenna as a trigger signal is sent to the control terminalafter demodulation and shaping by the receiver.4. It describes the development and implementation of the controller based on theCPLD. Through the CPLD’s online programming, it makes the circuit accomplish thelogic functions in accordance with requirements of the code. 5. It describes the commissioning of the control system with other circuit. And itmakes a comparison of test results and simulation results.The research work above makes a foundation for SART to achieve low powerconsumption, low cost and compact design.