In this work, the comprehensive influence of different reflector subtended angle values and the displacement of feed on a parabolic reflector antenna was studied. There are two main reasons for this research; one is that the actual performance of antennas is worse than indicated in theoretical analysis, and the other is that the deep or derived impacts of some deviations cannot be taken into sufficient account for antenna design. Differing from the ideal theoretical analysis and calculation, a parabolic reflector antenna with a pyramidal horn feed was designed to make the antenna design more suitable for the actual project. The performance of the antenna with different deviations of the feed under different reflector subtended angles was then given. This research has higher practical guiding significance in terms of margin consideration for the design of antennas in engineering.
For the purpose of fulfilling the low sidelobe level (SLL) requirements for spaceborne phased array antenna pattern synthesis, this paper proposes a new improved whale optimization algorithm (IWOA). As a type of new heuristic algorithm inspired by whale hunting behavior, WOA has the advantages of simple structure, few parameters, fast optimization speed, and high precision. In this paper, improvements are made in three aspects of adaptive weight, spiral coefficient optimization, and optimal neighborhood perturbation, and the proposed algorithm is successfully applied to the intelligent calculation of antenna synthesis. In light of the engineering requirements, the mathematical model of the optimization problem is established, and the desired antenna pattern with high gain and low sidelobe is obtained using IWOA under the constraint that the amplitude variation is within 20 dB. Simulation results demonstrate that IWOA is superior in maximum sidelobe level (MSLL) suppression and convergence. Consequently, EM simulations were conducted on a 64-element planar array, with the results consistent with the theoretical simulation, verifying the feasibility and effectiveness of the proposed algorithm.
This work investigates the effects of the surface errors of the satellite antenna on the detection performance of the space VLBI system. First, the relationship between the surface errors and the antenna gain loss is analyzed, and then the influence of the gain loss on the detection performance of the VLBI system is analyzed. Both the uniform and nonuniform distributions of errors are studied, and the second-order Taylor expansion is performed on the errors to simplify the calculation. When the errors distribute nonuniformly, the solver SCIP is adopted to solve the corresponding distribution, which leads to the maximum gain loss of the antenna. Taking the VLBI system with two base stations as the object, and each station’s radio telescope is a hoop truss deployable antenna with 30 m aperture, the effects of antenna gain loss on the detection capability of the radio telescope and the delay error of the VLBI system are studied. The study of extreme working conditions will have a higher guiding significance for the overall link analysis of practical projects.