Design Of RF System Of P-band Instantaneous Polarization Radar

Instantaneous polarization radar has the extremely important military value in terms of the improvement of the detective performance and perceptual capacity in the complex situation of war, as well as the aspect of anti-jamming, anti-disguising and anti-low-altitude-penetration. The RF subsystem is a critical element in the instantaneous polarization radar system, the major function of which is to detect the scattering property of radar target, at the same time measuring the four parameters of the polarization scattering matrix of the target. The thesis undertakes research, centering about the design of the RF subsystem.The thesis first discusses the RF subsystem's gross structure design, and analyses the whole index of the system. The principle part of the RF subsystem consists of receiving and transmitting antenna arrays and the dual-channel receiving and transmitting circuit system.Circuit system working as transmitters and receivers consists of perpendicular polarized reception/ transmitting channel, horizontal polarized reception/transmitting channel, a section for frequency synthesis and control and power supply.Considering the various forms of antenna performance parameters, this thesis adopts Yagi-Uda antenna as antenna array's unit. The use of electromagnetic simulation software such as HFSS and CST to simulate and analyses antenna array, using a special layout of the antenna array and the antenna unit of the power to implement specific weight incentives to achieve the narrow-beam, low-sidelobe antenna array. The actual results of the tests and simulation results have good consistency.Considering the similarity of the structure of the circuit, and that between the various parts to facilitate the connection, after careful overall layout, the circuit system is divided into frequency conversion modules, T/R modules, Frequency synthesizer control modules, power modules, and other modules to development. Focus on the design process of the frequency converter, filters, amplifiers and frequency synthesizer.The test results of the RF subsystem technical parameters may reflect the development of technology. This article describes the actual test used in the test methods and test instruments, to make the test results are more accurate and more realistically reflect the actual performance and quality.The ultimate realization of the instantaneous polarization radar RF subsystems could not only meet the requirements of the experimental application, but also has highly cost-effective. The key technologies of this system are: low sidelobe compact antenna technology, ultra-low-noise receiver front-end design and automatic power balance technology.