Investigation on spectrum estimation extrapolation method of antenna measurement

Measurement precision of Low frequency antenna is poor for the apparent reflection from absorbers in anechoic chamber. According time-frequency transform theory, a certain bandwidth signal holds the ability of certain range resolution, so a time-domain antenna measurement model can be built. Based on real frequency bandwidth, extrapolating the frequency band to lower frequency and higher frequency by spectrum estimation, thus the broader frequency bandwidth is gained, higher range resolution can be realized, so multi-path reflection can be isolated and removed, as a result, measuring precision of antenna pattern will be improved apparently. Results from simulation and experiment show that the method is correct and effective.