The Window Design Method
The basic idea behind the design of linear-phase FIR filters using the window
method is to choose a proper ideal frequency-selective filter [which always has
a noncausal, infinite duration impulse response] and then truncate its impulse
response hd[n] to obtain a linear-phase and causal FIR filter h[n]. To truncate the
impulse response of the ideal filter a time window w[n] is used. Available windows
in Matlab are rectangular [or boxcar in Matlab], bartlett, hamming, hanning
The code performs a number (ITERS) of iterations of the
Bailey s 6-step FFT algorithm (following the ideas in the
CMU Task parallel suite).
1.- Generates an input signal vector (dgen) with size
n=n1xn2 stored in row major order
In this code the size of the input signal
is NN=NxN (n=NN, n1=n2=N)
2.- Transpose (tpose) A to have it stored in column
major order
3.- Perform independent FFTs on the rows (cffts)
4.- Scale each element of the resulting array by a
factor of w[n]**(p*q)
5.- Transpose (tpose) to prepair it for the next step
6.- Perform independent FFTs on the rows (cffts)
7.- Transpose the resulting matrix
The code requires nested Parallelism.
