--- /dev/null
+#!/usr/bin/env python
+#
+
+
+from gnuradio import gr, eng_notation
+from gnuradio import blks2
+from gnuradio.eng_option import eng_option
+from optparse import OptionParser
+import math, time, sys, scipy, pylab
+from scipy import fftpack
+
+class fmtx(gr.hier_block2):
+ def __init__(self, lo_freq, audio_rate, if_rate):
+
+ gr.hier_block2.__init__(self, "build_fm",
+ gr.io_signature(1, 1, gr.sizeof_float), # Input signature
+ gr.io_signature(1, 1, gr.sizeof_gr_complex)) # Output signature
+
+ fmtx = blks2.nbfm_tx (audio_rate, if_rate, max_dev=5e3, tau=75e-6)
+
+ # Local oscillator
+ lo = gr.sig_source_c (if_rate, # sample rate
+ gr.GR_SIN_WAVE, # waveform type
+ lo_freq, #frequency
+ 1.0, # amplitude
+ 0) # DC Offset
+ mixer = gr.multiply_cc ()
+
+ self.connect (self, fmtx, (mixer, 0))
+ self.connect (lo, (mixer, 1))
+ self.connect (mixer, self)
+
+class fmtest(gr.top_block):
+ def __init__(self):
+ gr.top_block.__init__(self)
+
+ self._nsamples = 1000000
+ self._audio_rate = 8000
+
+ # Set up N channels with their own baseband and IF frequencies
+ self._N = 5
+ chspacing = 16000
+ freq = [10, 20, 30, 40, 50]
+ f_lo = [0, 1*chspacing, -1*chspacing, 2*chspacing, -2*chspacing]
+
+ self._if_rate = 4*self._N*self._audio_rate
+
+ # Create a signal source and frequency modulate it
+ self.sum = gr.add_cc ()
+ for n in xrange(self._N):
+ sig = gr.sig_source_f(self._audio_rate, gr.GR_SIN_WAVE, freq[n], 0.5)
+ fm = fmtx(f_lo[n], self._audio_rate, self._if_rate)
+ self.connect(sig, fm)
+ self.connect(fm, (self.sum, n))
+
+ self.head = gr.head(gr.sizeof_gr_complex, self._nsamples)
+ self.snk_tx = gr.vector_sink_c()
+ self.channel = blks2.channel_model(0.1)
+
+ self.connect(self.sum, self.head, self.channel, self.snk_tx)
+
+
+ # Design the channlizer
+ self._M = 10
+ bw = chspacing/2.0
+ t_bw = chspacing/10.0
+ self._chan_rate = self._if_rate / self._M
+ self._taps = gr.firdes.low_pass_2(1, self._if_rate, bw, t_bw,
+ attenuation_dB=100,
+ window=gr.firdes.WIN_BLACKMAN_hARRIS)
+ tpc = math.ceil(float(len(self._taps)) / float(self._M))
+
+ print "Number of taps: ", len(self._taps)
+ print "Number of channels: ", self._M
+ print "Taps per channel: ", tpc
+
+ self.pfb = blks2.pfb_channelizer_ccf(self._M, self._taps)
+
+ self.connect(self.channel, self.pfb)
+
+ # Create a file sink for each of M output channels of the filter and connect it
+ self.fmdet = list()
+ self.squelch = list()
+ self.snks = list()
+ for i in xrange(self._M):
+ self.fmdet.append(blks2.nbfm_rx(self._audio_rate, self._chan_rate))
+ self.squelch.append(blks2.standard_squelch(self._audio_rate*10))
+ self.snks.append(gr.vector_sink_f())
+ self.connect((self.pfb, i), self.fmdet[i], self.squelch[i], self.snks[i])
+
+ def num_tx_channels(self):
+ return self._N
+
+ def num_rx_channels(self):
+ return self._M
+
+def main():
+
+ fm = fmtest()
+
+ tstart = time.time()
+ fm.run()
+ tend = time.time()
+
+ if 1:
+ fig1 = pylab.figure(1, figsize=(12,10), facecolor="w")
+ fig2 = pylab.figure(2, figsize=(12,10), facecolor="w")
+ fig3 = pylab.figure(3, figsize=(12,10), facecolor="w")
+
+ Ns = 10000
+ Ne = 100000
+
+ fftlen = 8192
+ winfunc = scipy.blackman
+
+ # Plot transmitted signal
+ fs = fm._if_rate
+
+ d = fm.snk_tx.data()[Ns:Ns+Ne]
+ sp1_f = fig1.add_subplot(2, 1, 1)
+
+ X,freq = sp1_f.psd(d, NFFT=fftlen, noverlap=fftlen/4, Fs=fs,
+ window = lambda d: d*winfunc(fftlen),
+ visible=False)
+ X_in = 10.0*scipy.log10(abs(fftpack.fftshift(X)))
+ f_in = scipy.arange(-fs/2.0, fs/2.0, fs/float(X_in.size))
+ p1_f = sp1_f.plot(f_in, X_in, "b")
+ sp1_f.set_xlim([min(f_in), max(f_in)+1])
+ sp1_f.set_ylim([-120.0, 20.0])
+
+ sp1_f.set_title("Input Signal", weight="bold")
+ sp1_f.set_xlabel("Frequency (Hz)")
+ sp1_f.set_ylabel("Power (dBW)")
+
+ Ts = 1.0/fs
+ Tmax = len(d)*Ts
+
+ t_in = scipy.arange(0, Tmax, Ts)
+ x_in = scipy.array(d)
+ sp1_t = fig1.add_subplot(2, 1, 2)
+ p1_t = sp1_t.plot(t_in, x_in.real, "b-o")
+ #p1_t = sp1_t.plot(t_in, x_in.imag, "r-o")
+ sp1_t.set_ylim([-5, 5])
+
+ # Set up the number of rows and columns for plotting the subfigures
+ Ncols = int(scipy.floor(scipy.sqrt(fm.num_rx_channels())))
+ Nrows = int(scipy.floor(fm.num_rx_channels() / Ncols))
+ if(fm.num_rx_channels() % Ncols != 0):
+ Nrows += 1
+
+ # Plot each of the channels outputs. Frequencies on Figure 2 and
+ # time signals on Figure 3
+ fs_o = fm._audio_rate
+ for i in xrange(len(fm.snks)):
+ # remove issues with the transients at the beginning
+ # also remove some corruption at the end of the stream
+ # this is a bug, probably due to the corner cases
+ d = fm.snks[i].data()[Ns:Ne]
+
+ sp2_f = fig2.add_subplot(Nrows, Ncols, 1+i)
+ X,freq = sp2_f.psd(d, NFFT=fftlen, noverlap=fftlen/4, Fs=fs_o,
+ window = lambda d: d*winfunc(fftlen),
+ visible=False)
+ #X_o = 10.0*scipy.log10(abs(fftpack.fftshift(X)))
+ X_o = 10.0*scipy.log10(abs(X))
+ #f_o = scipy.arange(-fs_o/2.0, fs_o/2.0, fs_o/float(X_o.size))
+ f_o = scipy.arange(0, fs_o/2.0, fs_o/2.0/float(X_o.size))
+ p2_f = sp2_f.plot(f_o, X_o, "b")
+ sp2_f.set_xlim([min(f_o), max(f_o)+0.1])
+ sp2_f.set_ylim([-120.0, 20.0])
+ sp2_f.grid(True)
+
+ sp2_f.set_title(("Channel %d" % i), weight="bold")
+ sp2_f.set_xlabel("Frequency (kHz)")
+ sp2_f.set_ylabel("Power (dBW)")
+
+
+ Ts = 1.0/fs_o
+ Tmax = len(d)*Ts
+ t_o = scipy.arange(0, Tmax, Ts)
+
+ x_t = scipy.array(d)
+ sp2_t = fig3.add_subplot(Nrows, Ncols, 1+i)
+ p2_t = sp2_t.plot(t_o, x_t.real, "b")
+ p2_t = sp2_t.plot(t_o, x_t.imag, "r")
+ sp2_t.set_xlim([min(t_o), max(t_o)+1])
+ sp2_t.set_ylim([-1, 1])
+
+ sp2_t.set_xlabel("Time (s)")
+ sp2_t.set_ylabel("Amplitude")
+
+
+ pylab.show()
+
+
+if __name__ == "__main__":
+ main()
projects / debian / gnuradio / blobdiff