Antenna Planar Near-Field Measurement And Its Error Analysis

With the development of antenna in recent years,the integration of multiple disciplines,antenna measurement gradually tends to be complex and precise,and the contemporary progress of science and technology has also put forward new indicators and requirements for antennas,these new indicators and requirements also bring great challenges for the study of antennas.And antenna measurement is the standard to distinguish a good or bad performance of antenna,so in the modern complex electromagnetic environment,how to accurately measure the weak antenna signal becomes a problem.The importance of antenna measurement as a measurement technology for the accurate measurement of antennas is self-evident.Due to the modern complex electromagnetic environment,the traditional measurement method will be seriously affected,resulting in a large measurement error,so the near-field measurement gradually enter people’s vision,near-field measurement refers to the distance to be measured antenna 3～10 range,through the sampling probe for data acquisition,to obtain the electromagnetic field amplitude phase distribution in the near-field area,and then through a strict mathematical calculation,calculate the antenna far-field area radiation characteristics.This paper starts the work with antenna near-field measurement,and introduces the development history of near-field measurement and the status of domestic and foreign research.After that,the basic theory of antenna planar near-field measurement is introduced,including planar near-far field transformation theory,standing phase method and probe correction theory.Finally,the antenna near-field measurement system in this laboratory is introduced,including the composition and functions of the antenna near-field measurement system.The middle part is based on the theory of planar near and far field transformations,firstly,the theoretical far field directional map is derived for the standard gain angle cone horn antenna,and then the antenna is compared with various results such as HFSS modeling simulation,microwave darkroom experimental measurement,and NSI measurement results to verify the effectiveness and correctness of the algorithm,which is more accurate,practical and convincing compared with the pure simulation results.On top of this result,the finite scan plane truncation error and scan plane position error are explored and compensated accordingly by relevant correction theories combined with experimental measurements and simulations,and compared and analyzed with the theoretical results to further improve the measurement accuracy.Finally,there are two practical engineering applications,including radome near-field measurements,antenna near-field measurement data processing software and antenna near-field measurement 2D plotting software development.The antenna hood near field measurement is mainly to measure and compare the single pulse antenna with and without hood,and to analyze the hood related electrical parameters.The antenna near-field measurement data processing software mainly retrieves,displays and saves multiple test data into *.txt files,which greatly improves the data processing speed.The antenna near-field measurement 2D plotting software is to import the processed *.txt file into the plotting software to draw the antenna direction,which further improves the data visualization.In this paper,the experimental measurement and simulation results are in good accordance with the comparison of theoretical results,in practical engineering,has a certain practicality,for antenna plane near field measurement,has a certain reference value.