Error Correction Of Antenna Array For In-situ Radiated Emission Measurement And Research On The Vivaldi Antenna Array

With the development and application of electronic information technology in many fields,the types and quantities of electromagnetic interference signals in the environment are increasing,which makes it difficult for the environmental level to meet the standard requirements in the measurement of in-situ radiated emission.In order to suppress environmental signals,the combination of array signal processing and adaptive noise cancellation is an effective method.As an important part of the receiving system of this method,the receiving antenna array is a key factor that affects the accuracy of radiation emission measurement.Therefore,it is necessary to study the error correction method of the receiving array.In addition,in order to further realize the suppression of complex interference signals by using fewer array elements,it is of great significance to develop a directional receiving antenna array suitable for radiation emission measurement.Firstly,the mutual coupling calibration method of the receiving array is studied.According to the characteristics of array signal processing in the in-situ radiated emission measurement,a method of adding auxiliary array elements combined with the coupled pattern method is proposed.This method uses the auxiliary array elements method to solve the edge effect problem of the array,and then combines the improved pattern multiplication method to deal with the mutual coupling problem.so that the subsequent array signal processing can be carried out directly on the received data obtained by the receiving device,and the process of mutual coupling calibration is simplified.Then,the method of amplitude and phase error correction with single auxiliary source is introduced,and the correction process of this method in radiated emission measurement is given.Finally,the effectiveness of the method is verified by experiments.In this paper,an antipodal Vivaldi antenna array with a working frequency range of2GHz?8GHz is developed,and the active voltage standing wave ratio(active VSWR)of the array elements in the whole frequency range is less than 3.First,the basic size of the antenna is determined according to the radiation principle and design requirements of the Vivaldi antenna.And then,the impedance and radiation characteristics are simulated to optimize the relevant parameters of the antenna.Finally,the high-frequency antenna array is analyzed,and the form of the array antenna is determined by the simulation of the whole antenna array and the active characteristics of the array elements.In addition,a low-frequency antipodal Vivaldi antenna array with a reflector plate is designed.Its working frequency range is from 300 MHz to 2GHz.In the array,the active VSWR of the array elements in the whole frequency range is less than 4.3,and the front-to-back ratio of the array is greater than 10 d B.The impedance and radiation characteristics of the designed high-frequency and lowfrequency antenna are tested,and the results are basically consistent with the simulation results.Finally,the experiment shows that using the developed antenna array combined with the error correction method can accurately estimate the directions of arrival(DOAs)of the signals,complete the suppression of the interference signals,and then restore the radiated emission signal value of the electronic equipment under test.