Inverse estimation of antenna model for ground penetrating radar using ensemble Kalman filter

Abstract

In order to estimate the unknown parameters of the antenna model in the simulation of electromagnetic wave propagation for a radar test, we incorporated the ensemble Kalman filter, a data assimilation method, to the finite time domain difference method (FDTD method). As a fundamental study of the application of the method, twin experiment was conducted to simulate radar tests in a simple medium to verify the accuracy of the estimation of antenna model parameters. The validation analysis showed that the proposed method is capable of simultaneously estimating unknown parameters of the antenna model. Sensitivity analysis for various analytical conditions shows that the time increment has a large impact on the ensemble approximation of the error covariance matrix of the state vector and, consequently, on the estimation accuracy. Also, the time increment should be sufficiently smaller than the upper limit of the time increment that satisfies the Courant condition.