Based On Delay-related Aperture Synthesis Radiometer Measurement Principle Verification

In order to achieve a high spatial resolution,the geostationary orbit satellite payload requires a large number array of antenna,and each antenna requires a receiving channel,which increases the weight and size of the payload.The delay-related aperture synthesis radiometer(ASR)can greatly reduce the number of channels and effectively reduce the complexity of the system,and provides a feasible solution to solve the problem of excessive weight and size on the payload.The paper mainly validates the principle of delay-related aperture synthesis radiometer measurement from the experiment.During the experiment,we have obtained the following research results :1)The thesis study the principle and method of delay-related aperture synthesis radiometer measurement.Compared with the characteristics of aperture synthesis radiometer,the array factor,spatial resolution and output signal noise of delay-related aperture synthesis radiometer are given.Theoretically,the time-delayed aperture synthesis radiometer measurement method can also achieve the same effect as the aperture synthesis radiometer measurement method.2)Design the delay module to realize the addition of the delay signals.The material and length of the delay line were analyzed.Finally,the 16m-coaxial is selected as the delay line.It is proposed to use the power divider to realize the addition of the two signals.In the experiment,the AV36580 A vector network analyzer is used to measure the parameters of the coaxial,power divider and low noise amplifier.The loss of the coaxial is about 8dB,and the loss of the delay module is about 7dB.It is proposed to use two low noise amplifiers to make up the loss of coaxial and the delay module.When the voltage values of the two low noise amplifiers connected to the delay module are 6.7V and 5.3V,the loss of the delay module can be reduced to about 0.3dB.3)Establishing the system of time-delay-related aperture synthesis radiometer and conducting the measurement experiment about delay-related aperture synthesis radiometer.By analyzing the time-domain and frequency-domain spectrum of the delay-related data,it is found that the results of time-domain and frequency-domain spectrum are in agreement with the theoretical analysis values,which proves that the established delay system can measurethe delay-added data,and processes the data to verify the delay-related theory.In order to compare the results of the delay-related aperture synthesis radiometer data obtained by the aperture synthesis radiometer was used to verify the delay theory at the simulation level.Finally the delay correlation theory is experimentally verified.4)Analyze the errors generated in the experiment,the reason why small correlation peaks occur is analyzed when the delay time is not 20 times,the reason why the delay-related data calculated auto-correlation peak is less than the auto-correlation peak obtained by the simulation is analyzed,and proposed the improved measurement scheme to get the corrected results.