From 9b47ed5a0efa26a25a40d438ea8028c51ea18312 Mon Sep 17 00:00:00 2001
From: Mike Jameson <mike@scanoo.com>
Date: Sun, 24 Mar 2013 17:12:45 +0000
Subject: uhd: updated usrp_spectrum_sense with frequency readout
---
gr-uhd/examples/python/usrp_spectrum_sense.py | 45 +++++++++++++++++++++------
1 file changed, 35 insertions(+), 10 deletions(-)
(limited to 'gr-uhd/examples/python/usrp_spectrum_sense.py')
diff --git a/gr-uhd/examples/python/usrp_spectrum_sense.py b/gr-uhd/examples/python/usrp_spectrum_sense.py
index 32980adbfa..71f1f8c266 100755
--- a/gr-uhd/examples/python/usrp_spectrum_sense.py
+++ b/gr-uhd/examples/python/usrp_spectrum_sense.py
@@ -104,7 +104,10 @@ class my_top_block(gr.top_block):
help="time to delay (in seconds) after changing frequency [default=%default]")
parser.add_option("", "--dwell-delay", type="eng_float",
default=10e-3, metavar="SECS",
- help="time to dwell (in seconds) at a given frequncy [default=%default]")
+ help="time to dwell (in seconds) at a given frequency [default=%default]")
+ parser.add_option("", "--channel-bandwidth", type="eng_float",
+ default=12.5e3, metavar="Hz",
+ help="channel bandwidth of fft bins in Hz [default=%default]")
parser.add_option("-F", "--fft-size", type="int", default=256,
help="specify number of FFT bins [default=%default]")
parser.add_option("", "--real-time", action="store_true", default=False,
@@ -122,8 +125,9 @@ class my_top_block(gr.top_block):
# swap them
self.min_freq, self.max_freq = self.max_freq, self.min_freq
- self.fft_size = options.fft_size
-
+ self.fft_size = options.fft_size
+ self.channel_bandwidth = options.channel_bandwidth
+
if not options.real_time:
realtime = False
else:
@@ -147,14 +151,14 @@ class my_top_block(gr.top_block):
if(options.antenna):
self.u.set_antenna(options.antenna, 0)
- usrp_rate = options.samp_rate
+ self.usrp_rate = usrp_rate = options.samp_rate
self.u.set_samp_rate(usrp_rate)
dev_rate = self.u.get_samp_rate()
- s2v = gr.stream_to_vector(gr.sizeof_gr_complex, self.fft_size)
+ s2v = gr.stream_to_vector(gr.sizeof_gr_complex, self.fft_size)
mywindow = window.blackmanharris(self.fft_size)
- fft = gr.fft_vcc(self.fft_size, True, mywindow)
+ fft = gr.fft_vcc(self.fft_size, True, mywindow, True)
power = 0
for tap in mywindow:
power += tap*tap
@@ -185,8 +189,8 @@ class my_top_block(gr.top_block):
dwell_delay)
# FIXME leave out the log10 until we speed it up
- #self.connect(self.u, s2v, fft, c2mag, log, stats)
- self.connect(self.u, s2v, fft, c2mag, stats)
+ #self.connect(self.u, s2v, fft, c2mag, log, stats)
+ self.connect(self.u, s2v, fft, c2mag, stats)
if options.gain is None:
# if no gain was specified, use the mid-point in dB
@@ -194,7 +198,7 @@ class my_top_block(gr.top_block):
options.gain = float(g.start()+g.stop())/2.0
self.set_gain(options.gain)
- print "gain =", options.gain
+ print "gain =", options.gain
def set_next_freq(self):
target_freq = self.next_freq
@@ -227,6 +231,20 @@ class my_top_block(gr.top_block):
def main_loop(tb):
+
+ def nearest_freq(freq, channel_bandwidth):
+ freq = round(freq / channel_bandwidth, 0) * channel_bandwidth
+ return freq
+
+ def bin_freq(i_bin, center_freq):
+ hz_per_bin = tb.usrp_rate / tb.fft_size
+ freq = center_freq - (tb.usrp_rate / 2) + (hz_per_bin * i_bin)
+ freq = nearest_freq(freq, tb.channel_bandwidth)
+ return freq
+
+ bin_start = int(tb.fft_size * ((1 - 0.75) / 2))
+ bin_stop = int(tb.fft_size - bin_start)
+
while 1:
# Get the next message sent from the C++ code (blocking call).
@@ -234,7 +252,7 @@ def main_loop(tb):
m = parse_msg(tb.msgq.delete_head())
# Print center freq so we know that something is happening...
- print m.center_freq
+ #print "m.center_freq:", m.center_freq
# FIXME do something useful with the data...
@@ -244,6 +262,13 @@ def main_loop(tb):
# m.raw_data is a string that contains the binary floats.
# You could write this as binary to a file.
+ for i_bin in range(bin_start, bin_stop):
+
+ # create signal object to find matching signals
+ freq = int(bin_freq(i_bin, m.center_freq))
+ power = float(m.data[i_bin])
+
+ print freq, power
if __name__ == '__main__':
t = ThreadClass()
--
cgit v1.2.3