G’day,
I have a problem using the above function. My assumption is that
band_reject
means the rejection of a portion of a spectrum as used in notch filters.
The
following filter design does not show up the expected notch in the
spectrum.
To the contrary, the spectrum shows a slight increase of the noise
contents
at 1000Hz.
sample_rate = 48000
frequency = 1000
bandwidth = 100
coeffs = gr.firdes.band_reject(
1.0,
sample_rate,
frequency - (bandwidth/2),
frequency + (bandwidth/2),
50,
gr.firdes.WIN_HANN)
filter = gr.fir_filter_fcc(1, coeffs)
The band/low/high pass filters work as expected. I use gr.noise_source
and
fft_sink to verify the design. What am I doing wrong?
cheerio Berndt