# Boston, MA 02110-1301, USA.
#
-from gnuradio import gr
+from gnuradio import gr, optfir
class pfb_arb_resampler_ccf(gr.hier_block2):
'''
streams. This block is provided to be consistent with the interface to the
other PFB block.
'''
- def __init__(self, rate, taps, flt_size=32):
+ def __init__(self, rate, taps=None, flt_size=32, atten=100):
gr.hier_block2.__init__(self, "pfb_arb_resampler_ccf",
gr.io_signature(1, 1, gr.sizeof_gr_complex), # Input signature
gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature
self._rate = rate
- self._taps = taps
self._size = flt_size
+ if taps is not None:
+ self._taps = taps
+ else:
+ # Create a filter that covers the full bandwidth of the input signal
+ bw = 0.4
+ tb = 0.2
+ ripple = 0.1
+ #self._taps = gr.firdes.low_pass_2(self._size, self._size, bw, tb, atten)
+ made = False
+ while not made:
+ try:
+ self._taps = optfir.low_pass(self._size, self._size, bw, bw+tb, ripple, atten)
+ made = True
+ except RuntimeError:
+ ripple += 0.01
+ made = False
+ print("Warning: set ripple to %.4f dB. If this is a problem, adjust the attenuation or create your own filter taps." % (ripple))
+
self.pfb = gr.pfb_arb_resampler_ccf(self._rate, self._taps, self._size)
self.connect(self, self.pfb)