Near Field millimeter Wave Antenna Measurements

Abstract: In the real world, understanding an antenna's radiation pattern is crucial for its proper utilization. Typically, antennas are tested in the far-field region, where the radiation lobes are fully developed and phase errors are less than pi/8. However, due to some drawbacks like an increase in far-field distance for antenna arrays, researchers have shifted towards near-field measurements. These near-field measurements are then used to implement algorithms that predict the antenna's radiation pattern in the far field. In this thesis, an algorithm is developed in MATLAB to predict the far-field pattern of a horn antenna and estimate its gain at frequencies of 28 GHz and 39 GHz. Additionally, probe compensation is implemented to eliminate the influence of the probe's radiation pattern. In this study, planar near-field measurement techniques have been employed to scan the radiation pattern, which comes with angle constraints. Additionally, an effort has been made to extend this approach to active antennas by utilizing a Phased Array Antenna Module (PAAM) board. However, due to time limitations, only an estimation of the gain of the PAAM board has been conducted. In the discussion of the results, potential reasons have been identified to justify any deviations from the expected results. Finally, future work has been proposed to enhance the implemented algorithm and achieve more accurate results.