u2061 u025b r u03c3 u2202 e approx u2202 u025b r u2062 u03b4 u025b r u2202 e approx u2202 u03c3 u2062 u03b4 u03c3 1 u03c6 e true u2061 u025b r u03c3 u2245 u03c6 e approx u2061 u025b r u03c3 u2202 u03c6 e approx u2202 u025b r u2062 u03b4 u025b r u2202 u03c6 e approx u2202 u03c3 u2062 u03b4 u03c3 2 where e is the electric field u03c6 e is electric field phase and u03b5 r and u03c3 are the permittivity and conductivity respectively with reference now to fig2 there are illustrated exemplary steps employed to obtain a microwave image using apparatus and methodologies according to the present subject matter an exemplary reconstruction algorithm in accordance with the present subject matter can be summarized as corresponding to a five step process a first step in the exemplary reconstruction algorithm corresponds to computing the amplitude and phase of electric field at measurement sites based on an initial guess for material properties u03b5 g u03c3 g according to the present subject matter this initial guess is based on ultrasound recovered profiles and is obtained using an algorithm based on so called bayliss and turkel radiation boundary condition a main step in reconstruction of permittivity and conductivity profiles based on experimental data corresponds to a so called forward or direct computation.