Time-varying signals analysis using squared analytic signals

Wigner distribution (WD) can provide for high frequency- or time- resolution, but its nonlinear property poses problems when applied to signals with multiple frequency components. This paper proposes an alternative to WD with improved performance for such signals, based on a consideration why WD offers high resolution. The observed data is first converted to analytic signals, which are then subjected to Fourier transform after squaring. Experimental results revealed its superiority over WD for multi-component signals.