Time reversal imaging of suspended target in strong reverberation

The weighted wideband time-reversal imaging approach of full signal subspaces is proposed. Provided that the extended target is composed of an infinite number of independent scatterers, time-reversal imaging of all signal subspaces is combined over the entire bandwidth at the locations of suspected targets. On the bottom of a laboratorywater waveguide, a cylindrical shell was used to produce reverberation. Two experiments are carried out. One is that an extended target is suspended near the cylindrical shell, and then the echo seems in different time window with the reverberation reflected by the cylindrical shell. The other is that a point-like target is suspended above the cylindrical shell, thus the echo and the reverberation is in the same time window. The experimental results show that the proposed method has better imaging quality than that of the conventional time reversal imaging methods under the condition of the weak suspended target in a strong reverberation environment.