Research Of Electrical Characteristics For Complex System Of Antenna Arrayand Radome

This thesis has studied,aiming at the practical problems in the engineering design of radome, the optimal electricalperformance design of A sandwich and C sandwich plate radome based on the theory of equivalent transmission line. It has studiedthe calculation method of the electrical performance for antenna array-radome systemusing the physical optics(PO) algorithm, and the special software for calculating of the electric performance of the antenna array-radome systembased on graphical user interface has been developed. Based on the principle of phase interferometer for direction finding, the phase inconsistency of antenna array-radome system has been studied, and the relationship between the phase inconsistency and the direction finding error is analyzed.Moreover, the mechanism of the depolarization effect of the radome has been studied, and the compensation of the depolarization effect by changing the thickness of the core layer is proposed.The tangent ogive antenna radome as an example, according to the cross polarization isolation as optimization objective, it has designed the variable thickness of radome, using the PO method to verify the advantages of the cross polarization isolation performance of the core layer thickness of antenna radome.The main work is summarized as follows:(1) The optimal structure design of interlayer A and C sandwich plate radome.For abroadband radome with high transmission, the average rate for the optimal structure designs of A sandwich and C sandwich has been carried out, and the measured data was performed to verify the design method.(2) A special software for the calculation of the electric performance of the antenna array-radome system has been developed based on the graphical interface. The electrical performance of the antenna array-radome system has analyzed in detail by physical optics method.The calculation example has been analyzed by using the special electric performance calculation software, and the correctness of the algorithm is verified by the measured data.(3) Study of the phase inconsistency of the electrical performance of the antenna array-radome system. The principle of the antenna array as the phase interferometer used for direction finding function has been discussed. It has analyzed in detail that the accuracy and error sources of the interferometer and different direction finding methods havebeen compared with the measured data. The concept of phase inconsistency in the measurement of antenna array-radome has been improved and the relationship between its error and the direction finding error is analyzed. The positive correlation between the phase inconsistency and direction finding error is verified by the test data of a certain type of A sandwich radome.(4) Research on the compensation method of changing the thickness of the core layer to realize the polarization effect. Study on the mechanism of the polarization effect of radome, the calculation formula of the cross polarization isolation has been derived, and the influence of the parameters of the antenna on the depolarization effects has studied. For the example of a certain type of antenna radome,it has been analyzed the influence of the operating frequency, the incident angles and the parameters of radome on the depolarization effect. It is proposed varying core layer thickness compensation method to realize the depolarization effect.The tangent ogive radome as an example, combined with physical optics method to verify the variable core layer thickness of radome to achieve depolarization. Compared with the equal thickness radome, the proposed method is superior in terms of cross polarization isolation performance.