To detect over lapped echoes due to the thin pavement layers.we present at hicknessmeasurement approach for the very thin layer of pavement structures.The term “ thin” is relative to the incident wave length or pulse.By means of independent component analysis of noisy signals received by a single radar sensor,the over-lapped echoes can be successfully separated.Once the echoes from the topand bottom side of a thin layer have been separated,the time delay and the layer thickness determination follow immediately.Results of the simulation and real data verify the feasibility of the presented method.

       Keywords:thinlayer;thickness measurement;independent component analysis;ground penetrating nradar; pavement