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43 lines
1.0 KiB
Python
43 lines
1.0 KiB
Python
import numpy as np
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import common
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import wave
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import pylab
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Tsample = 1
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t = np.arange(int(Tsample * common.Fs)) * common.Ts
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sig = np.exp(2j * np.pi * common.Fc * t)
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sig_dump = common.dumps(sig)
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def send():
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p = wave.play('-', stdin=wave.sp.PIPE)
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while True:
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p.stdin.write(sig_dump)
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def recv():
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out = wave.record('-', stdout=wave.sp.PIPE).stdout
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while True:
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data = out.read(len(sig_dump))
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_, x = common.loads(data)
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x = x - np.mean(x)
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c = np.abs(np.dot(x, sig)) / (np.sqrt(0.5 * len(x)) * common.norm(x))
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z = np.dot(x, sig.conj()) / (0.5 * len(x))
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amp = np.abs(z)
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phase = np.angle(z)
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peak = np.max(np.abs(x))
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print('coherence={:.3f} amp={:.3f} phase={:.1f} peak={:.3f}'.format(c, amp, phase * 180 / np.pi, peak))
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def plot(x, z):
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pylab.plot(x)
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pylab.plot((sig * z).real)
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pylab.show()
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if __name__ == '__main__':
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import sys
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opt, = sys.argv[1:]
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if opt == 'send':
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send()
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if opt == 'recv':
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recv()
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