The Design And Implementation Of Antenna Simulator For Secondary Surveillance Radar

The secondary surveillance radar system is mainly composed of ground interrogator and airborne transponder,which work together in the way of "inquiry-response" to realize the continuous monitoring to the air target of civil aviation.After the monopulse technology was introduced into the secondary surveillance radar,the performance of secondary surveillance radar has been greatly improved,which makes it become the main means of ATC monitoring and is widely used in the world.However,with the development of monopulse secondary surveillance radar,it is more complicated and difficult to test and verify its functional performance during the development and production of secondary surveillance radar ground interrogator.Although the power,sensitivity and other conventional indicators can be quickly tested and verified by special/general instruments in the laboratory,the verification of key functions,such as the function and precision of monopulse angle measurement and the performance index also need to build a complete secondary surveillance radar system to verify with the combination of the inquiry antenna,turntable,airborne transponder and position calibration equipment,which needs high requirements on the testing site and supporting equipment,the realization mode is not flexible,and the cost of manpower and material resources is high.In this thesis,the secondary surveillance radar antenna simulator to be developed can construct the test environment of monopulse secondary surveillance radar ground interrogator under laboratory conditions,and verify the function and accuracy of monopulse angle measurement of monopulse interrogator of secondary surveillance radar without actual wireless joint test or test flight.A modern monopulse secondary surveillance radar ground interrogator is generally equipped with a antenna with three channels of Σ,Δ and Ω.The features of this kind of antenna are that as the changing that the plane deviates from the normal angle of the antenna,the amplitude and phase of the signal received by the differential beam will change regularly,and the angle of the aircraft deviation from the normal line can be obtained by changing the relationship between the two,which is also the basic principle of the monopulse angle measurement of the ground interrogator.First,in this paper,we introduced the development status of the secondary surveillance radar antenna simulator.Second,we studied the principle of the secondary surveillance radar antenna and the relationship between the antenna and the differential antenna pattern and the monopulse angle measurement,located the functional requirements on the secondary surveillance radar antenna simulator,and determined the working principle and overall architecture of the system.We focused on the study of the hardware and software realization scheme of the main control and cross-linking sequence generating unit of the equipment,and finished debugging the whole system.Finally,the test environment was constructed by combining the secondary surveillance radar ground interrogator and ATC response equipment,which verified the function and performance of the antenna simulator of the secondary surveillance radar,and determined the feasibility of using the system to construct the functional performance test environment of the monopulse secondary surveillance radar ground interrogator under laboratory conditions.The results of the test show that the system can construct the secondary surveillance radar simulation test environment flexibly based on the laboratory environment,which can greatly reduce the complexity of the test environment construction,and improve the efficiency and flexibility in testing of secondary surveillance radar ground interrogator with a good application scenario.