Wigner-Ville distribution Computes the wvd of the input signal. An analytic signal generator is called if the input signal is real. The supplied length of the analysis window defines whether the "true" wvd or a pseudo (windowed) wvd is computed. This version takes advantage of the reality of the wvd to increase calculation speed. Usage: tfd = wvd(signal, [lag_window_length] [,time_res] [, fft_length] ) Parameters: signal Input one dimensional signal to be analysed. An analytic signal is required for this function, however, if signal is real, a default analytic transformer routine will be called from this function before computing tfd. lag_window_length This is the data window length and controls the size of the kernel used for analysis (lag_window_length must be odd). The kernel used will be defined from -(lag_window_length+1)/2 to +(lag_window_length+1)/2 in both time and lag dimensions. time_res The number of time samples to skip between successive slices. Default vaule is 1. fft_length Zero-padding at the FFT stage of the analysis may be specified by giving an fft_length larger than lag_window_length. If fft_length is not specified, or is smaller than the lag_window_length, then the next highest power of two above lag_window_length is used. If fft_length is not a power of two, the next highest power of two is used. tfd The computed time-frequency distribution. size(tfd) will return [a, b], where a is the next largest power of two above fft_length, and b is floor(length(signal)/time_res) - 1. See Also: analyt, quadtfd