Hi
I looked at usrp_flex_band.py to see how blks2.analysis_filterbank is
implemented. The example runs on my PC.
I wrote a simple app where I want to decimate by 16 in the FPGA (no
HBF). So I have samples coming in at 4Msps. I then want to send this
stream to a 20 channel channeliser, resulting in output streams of
200ksps each. I want to test this by connecting an FM demodulator and
see if I can channelise a part of the FM band. Here is some of my
code.
self.u = usrp.source_c(decim_rate=16,fpga_filename=“std_2rx_0tx.rbf”)
if options.rx_subdev_spec is None:
options.rx_subdev_spec = pick_subdevice(self.u)
self.subdev = usrp.selected_subdev(self.u,options.rx_subdev_spec)
self.u.set_mux(usrp.determine_rx_mux_value(self.u,options.rx_subdev_spec))
print “Using RX d’board %s” % (self.subdev.side_and_name(),)
self.set_freq(options.freq)
taps = []
f1 = open(‘fir_lowpass.txt’,‘r’)
for line in f1:
tap = float(line)
taps.append(tap)
f1.close()
#taps = optfir.low_pass(1,usrp_rate,70e3,100e3,0.1,60)
pfb = blks2.analysis_filterbank(20,taps)
self.connect(self.u,pfb)
The application works until I try to connect the usrp source to the
filterbank. I get a Segmentation fault when I try to do this. Does
anyone know what might be wrong?
Thanks in advance.
Sebastiaan
–
Sebastiaan H.
Radar and Remote Sensing Group, University of Cape Town
Tel: +27 83 305 5667