Close range microwave imaging of human chest

An experimental system made of a large linear antenna array has been set up to obtain 2D images of the human chest with frame rate at microwave frequencies. Algorithms for reconstructing the images at close ranges and in a non homogeneous medium are described in this paper. Numerically calculated Green's functions are used to back propagate the observed signal to the image domain. Experimental results show that the image is better focused taking into account the inhomogeneous features of the propagation medium and that both breathing and heartbeat signals can be correctly extracted from the reconstructed images.