FIR filter using windowed impulse response
h = window(d,'window',fcnhndl)
h = window(d,win)
h = window(d,'window',fcnhndl) designs
an FIR filter using the specifications in filter specification object
Depending on the specification type of
d, the returned
filter is either a single-rate digital filter — a
or a multirate digital filter — an
fcnhndl is a handle to a filter design function
that returns a window vector, such as the
an optional argument that returns a window. You pass the function
window. Refer to example 1 in the following
section to see the function argument used to design the filter.
h = window(d,win) designs
a filter using the vector you supply in
length of vector
win must be the same as the impulse
response of the filter, which is equal to the filter order plus one.
Construct a lowpass filter specification object of order 10 with a cutoff frequency of 12 kilohertz. We use a sampling frequency of 48 kilohertz. Next we use a function handle to the function Kaiser to provide the window.
d=fdesign.lowpass('n,fc',10,12000,48000); Hd=window(d,'window',@kaiser); fvtool(Hd);