diff options
| -rw-r--r-- | dpd/src/Dab_Util.py | 12 | ||||
| -rw-r--r-- | dpd/src/phase_align.py | 48 |
2 files changed, 60 insertions, 0 deletions
diff --git a/dpd/src/Dab_Util.py b/dpd/src/Dab_Util.py index e85d45d..a4a271e 100644 --- a/dpd/src/Dab_Util.py +++ b/dpd/src/Dab_Util.py @@ -7,6 +7,7 @@ matplotlib.use('agg') import matplotlib.pyplot as plt import datetime import src.subsample_align as sa +import src.phase_align as pa from scipy import signal import logging @@ -123,6 +124,17 @@ class Dab_Util: rxframe_path = ('/tmp/rx_2_' + dt + '.iq') sig2.tofile(rxframe_path) + sig2 = pa.phase_align(sig2, sig1) + + sig2 = sa.subsample_align(sig2, sig1) + sig2 = pa.phase_align(sig2, sig1) + + if logging.getLogger().getEffectiveLevel() == logging.DEBUG: + txframe_path = ('/tmp/tx_3_' + dt + '.iq') + sig1.tofile(txframe_path) + rxframe_path = ('/tmp/rx_3_' + dt + '.iq') + sig2.tofile(rxframe_path) + logging.debug("Sig1_cut: %d %s, Sig2_cut: %d %s, off: %d" % (len(sig1), sig1.dtype, len(sig2), sig2.dtype, off)) return sig1, sig2 diff --git a/dpd/src/phase_align.py b/dpd/src/phase_align.py new file mode 100644 index 0000000..9e78483 --- /dev/null +++ b/dpd/src/phase_align.py @@ -0,0 +1,48 @@ +import numpy as np +from scipy import signal, optimize +import sys +import matplotlib.pyplot as plt +import datetime +import logging + + +def phase_align(sig, ref_sig): + """Do phase alignment for sig relative to the reference signal + ref_sig. + + Returns the aligned signal""" + + angle_diff = (np.angle(sig) - np.angle(ref_sig)) % (2. * np.pi) + + dt = datetime.datetime.now().isoformat() + fig_path = "/tmp/phase_align_" + dt + ".pdf" + plt.subplot(311) + plt.hist(angle_diff, bins=60, label="Angle Diff") + plt.xlabel("Angle") + plt.ylabel("Count") + plt.legend(loc=4) + + plt.subplot(312) + plt.plot(np.angle(ref_sig[:128]), label="ref_sig") + plt.plot(np.angle(sig[:128]), label="sig") + plt.xlabel("Angle") + plt.ylabel("Sample") + plt.legend(loc=4) + + angle = np.median(angle_diff) + logging.debug("Compensating phase by {} rad, {} degree.".format( + angle, angle*180./np.pi + )) + sig = sig * np.exp(1j * -angle) + + plt.subplot(313) + plt.plot(np.angle(ref_sig[:128]), label="ref_sig") + plt.plot(np.angle(sig[:128]), label="sig") + plt.xlabel("Angle") + plt.ylabel("Sample") + plt.legend(loc=4) + plt.tight_layout() + plt.savefig(fig_path) + plt.clf() + + return sig |