Analysis of Log-periodic Antenna Array on a Revolving Table

When a log-periodic antenna array is measured on a three-axis revolving table, because the revolving table is made of metal, it must have some influence on the antenna array´ measured results. This paper is to discuss the effect of revolving table on the radiation pattern of antenna array. By using software based on the moment method, the revolving table and the log-periodic antenna array are modeled. And the radiation patterns of the antenna array with and without revolving table are simulated at a few frequencies respectively. The results are compared and a conclusion is reached that the revolving table mainly affects the back lobe, the side lobes and the beam-width of the main lobe, and has little influence on the maximum radiation direction.