On the Reference Signal Parameters in the Cross Wigner-Ville Distribution Based Instantaneous Frequency Estimation Method

Discussion on the reference signal (RS) and the related parameters in the recently proposed Cross Wigner-Ville distribution (XWVD) based method for the signal components instantaneous frequency (IF) estimation is presented. By a convenient choice of the reference signal, cross-terms are formed in such a way that the XWVD between the analyzed signal (AS) and a reference signal (RS) yields a scaled image closely resembling the IF laws of the signal components. Following strict geometrical rules that govern interferences and relying on a reference signal for providing a well localized point in timefrequency plane, the time-frequency coordinates of the component IFs can be calculated in an automatic procedure. The effects of the reference signal's parameters on the method's performance are discussed and examples are given for various choices of the RS's parameters.