A fast time-delay calculation method in TWR detection through two layers

Time delay estimation is one of the key steps in target localization and high resolution imaging in Through-Wall-Radar signal processing procedure. In some typical TWR scenarios, electromagnetic wave propagates through two layers with different physical properties parameters. Traditional methods for the time-delay calculation in such situations are usually using three-dimensional searching algorithm or solving three variables equation of four times and tedious and time-wasting. This paper presents a new fast time-delay algorithm for electromagnetic wave propagating through two layers. An equation of two lateral distances through the walls can be established because of the fact that incident angle at upside of the walls equals to refracting angle at the downside of the walls. Total propagation path and time delay can be calculated by the two lateral distances subsequently. Simulating experiments prove the new algorithm is suitable for real-time time-delay calculation in TWR signal processing.