The Methods Of Efficient Computation And Real-time Compensation For EM Performance Of Conformal Load-bearing Array Antenna Under Dynamic Load

A combination of current antenna and bearing structure makes the conformal array antennas to be new equipment in aerial,space-based and land-based platforms,which has potential application in the future and has already aroused world attention.However,the mechanical and antenna performance can be more complicate than the current antenna as the strong coupling between the antenna and structure.The conformal array antennas must withstands the impact of a variety of loads,and then the structure will be deformed and further affects the EM performance of antenna.Therefore,this thesis focuses on the methods of efficient computation and real-time compensation for EM performance of conformal load-bearing array antenna.The main works are as follows:(1)To expand the limitation of low efficiency in traditional methods by predicting the antenna performance with transient structural analysis,the mode shape and load-related matrices are obtained by using the modal superposition method.Then combined with electromechanical coupling model,a high-efficiency method is developed to calculate the far-field pattern of the conformal array antenna under dynamic loads.A dynamic concentration load is applied to the conformal array antenna installed in wing to testify the new method.The results show that the new method can ensure the accuracy of computation,and improve the efficiency by 94%.(2)Combined with the high-efficiency method to predict antenna performance,the existed correction pointing error method and least squares method are further developed to be two real-time compensation methods for EM performance of the conformal array antenna.The dynamic concentration loads are also used to validate the two modified methods,and compare to original methods based on transient structural analysis,the developed methods can obtain the same compensation effect while substantially improve the efficiency by 94%.The new methods are more easily applied to achieve the real-time compensation of EM performance of the conformal array antenna under dynamic loads.(3)An actual wing of a high-altitude-long-endurance UAV has been used to further testify the high-efficiency calculation and compensation methods for the performance of antenna,and the national standards based gust turbulence calculated with Computational Fluid Dynamics(CFD)technique is added on the antenna.The computational results demonstrate that,with small structure deformation,the new performance predicting method can highly improve the efficiency with almost the same precision with traditional methods,and the developed two compensation methods can also achieve the same effect with original methods by using less time costs.Additionally,the compensation effects in main and side lobe areas of the developed methods agree well with the result of HFSS software,which further clearly shows the effectiveness of the developed methods.The practical application verifies the practicability and efficiency of the computational models and methods.