Void-layer thickness determination using spectrum optimization inversion method

Void characterization under pavements is an important aspect of airfield pavement evaluation and maintenance. This paper studies the thickness estimation of void-layer in runways based on the spectrum optimization inversion method, in which the impulse pair in the time domain corresponding to the upper and bottom interface of void-layer can be extracted based on the improved EM wave propagation model and system identification method we have proposed in other paper. The results demonstrate the method is valid and the estimation error of thickness is within 5%.