Model-based diameter estimation of reinforcing bar considering in accurate propagation time measurement of microwave radar

This report proposes how to realize a precise diameter estimation of buried objects in concrete structures, especially for reinforcing bars, by introducing two novel signal processing methods. One is a precise diameter estimation method based on a microwave propagation path model with the bi-static antenna configuration which is considering a separation between microwave transmitter and receiver. This separation cannot be ignored, since a buried depth of reinforcing bar in concrete structures is relatively shallow. The other is a high-accuracy propagation time measurement method. A peak time of reflected microwave has provided suitable information for a propagation time measurement with an appropriate compensation. It is confirmed that these two signal processing methods are useful for precise diameter estimation through various experiments.