Dynamic Analysis And Optimal Design Of Antenna Near-filed Test Scanner

The antenna near-field test scanner is an important part of the antenna near-field measurement system.Its dynamic performance determines the performance of the entire measurement system.The working conditions of the scanner are complex and diverse.In order to ensure its safety,reliability,high accuracy and high efficiency,it is necessary to carry out accurate mechanical analysis and dynamic optimization design.In this thesis,the ultra-large antenna near-field test scanner is taken as the research object,and the mechanical analysis and dynamics optimization are carried out by a combination of simulation analysis and experimental testing.Firstly,the finite element model of the structure was established with high accuracy and high efficiency as the objective.The rationality of the mass distribution was judged with the static analysis,and the dynamic stability of the structure under normal and extreme conditions was evaluated with the dynamics analysis.The results show that the overall performance of the structure is good,but there are stress concentration sites.Secondly,because the experimental analysis of the prototype body dynamics is subject to various factors such as experimental conditions and costs,a scale model was developed based on the dynamic similitude theory,and then the intrinsic characteristics and dynamic stability tests were conducted on it.And then the prototype characteristics were back-analyzed according to the similarity ratio and compared with the prototype simulation results.The results show that they are basically consistent,and the scaled model design is reasonable.Simultaneously,the rationality of the simulation analysis method is also verified.Finally,with the aim of improving the dynamic stability of the structure,a dynamic optimization model was established.Combined with the agent model technology,optimization algorithm were used to perform the dynamic optimization calculation.The results show that the optimized dynamic swing amplitude of the structure was improved by 45.82% than the prototype.