Generate quadratic class time-lag kernel functions This function generates kernel functions for various members of the quadratic class of Time-Frequency Distributions. Usage: kernel = quadknl( kernel_type, lag_window_length, full_kernel [, kernel_options] ); kernel_type is one of: 'wvd', 'smoothed', 'stft', 'rm', 'cw', 'bjc', 'zam','b' or 'mb'. Parameters: kernel The kernel is arranged in memory such that the zero time, zero lag point is located at kernel(0,0), and the positive time-lag quadrant extends to kernel(lag_window_length/2, lag_window_length/2). Negative values are indexed from lag_window_length-1 down to lag_window_length/2 + 1. kernel_type A string which defines the parent TF distribution generated by the kernel, one of: 'wvd' Wigner-Ville 'smoothed' Smoothed Wigner-Ville 'stft' Short-Time Fourier Transform 'rm' Rihaczek-Margenau 'cw' Choi-Williams 'bjc' Born-Jordan-Cohen 'zam' Zhao-Atlas-Marks 'b' B-distribution 'mb' Modified B-distribution lag_window_length Size of the generated kernel. Kernel will be defined in both time and lag dimensions from -(lag_window_length/2) to +(lag_window_length/2). full_kernel A boolean, indicating whether the full kernel is to be generated, or just the first quadrant (positive time and lag only). Passing 1 indicates the former case, while 0 indicates the latter. In the latter case, the returned size of the kernel will be (lag_window_length+1)/2 in both dimensions. kernel_options Some kernels require extra parameters: 'smoothed' kernel_option = length of smoothing window kernel_option2 = type of smoothing window, one of: 'rect', 'hann', 'hamm', 'bart' 'stft' kernel_option = length of smoothing window kernel_option2 = type of smoothing window, one of: 'rect', 'hann', 'hamm', 'bart' 'cw' kernel_option = Smoothing parameter 'zam' kernel_option = ZAM 'a' parameter 'b' kernel_option = B-distribution smoothing parameter beta 'mb' kernel_option = modified B-distribution parameter alpha See Also: quadtfd