A new scheme for estimating the number of natural resonances contained in the measurement of a conducting radar target response is presented. This method is a new application of the E-pulse concept and has the advantage, as compared with other schemes, of also providing the natural resonance values of the target response. To obtain the number of natural resonance an iterative minimisation procedure between the measured and the reconstructed response is applied. Results, using the response of a thin cylinder and a circular loop, demonstrate the insensitivity of the technique to additive random noise.<<ETX>>