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Diffstat (limited to 'dpd/src/Dab_Util.py')
-rw-r--r-- | dpd/src/Dab_Util.py | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/dpd/src/Dab_Util.py b/dpd/src/Dab_Util.py new file mode 100644 index 0000000..175b744 --- /dev/null +++ b/dpd/src/Dab_Util.py @@ -0,0 +1,232 @@ +# -*- coding: utf-8 -*- + +import datetime +import os +import logging +logging_path = os.path.dirname(logging.getLoggerClass().root.handlers[0].baseFilename) + +import numpy as np +import scipy +import matplotlib +matplotlib.use('agg') +import matplotlib.pyplot as plt +import src.subsample_align as sa +import src.phase_align as pa +from scipy import signal + +class Dab_Util: + """Collection of methods that can be applied to an array + complex IQ samples of a DAB signal + """ + def __init__(self, sample_rate): + """ + :param sample_rate: sample rate [sample/sec] to use for calculations + """ + self.sample_rate = sample_rate + self.dab_bandwidth = 1536000 #Bandwidth of a dab signal + self.frame_ms = 96 #Duration of a Dab frame + + def lag(self, sig_orig, sig_rec): + """ + Find lag between two signals + Args: + sig_orig: The signal that has been sent + sig_rec: The signal that has been recored + """ + off = sig_rec.shape[0] + c = np.abs(signal.correlate(sig_orig, sig_rec)) + + if logging.getLogger().getEffectiveLevel() == logging.DEBUG: + dt = datetime.datetime.now().isoformat() + corr_path = (logging_path + "/" + dt + "_tx_rx_corr.pdf") + plt.plot(c, label="corr") + plt.legend() + plt.savefig(corr_path) + plt.clf() + + return np.argmax(c) - off + 1 + + def lag_upsampling(self, sig_orig, sig_rec, n_up): + if n_up != 1: + sig_orig_up = signal.resample(sig_orig, sig_orig.shape[0] * n_up) + sig_rec_up = signal.resample(sig_rec, sig_rec.shape[0] * n_up) + else: + sig_orig_up = sig_orig + sig_rec_up = sig_rec + l = self.lag(sig_orig_up, sig_rec_up) + l_orig = float(l) / n_up + return l_orig + + def subsample_align_upsampling(self, sig1, sig2, n_up=32): + """ + Returns an aligned version of sig1 and sig2 by cropping and subsample alignment + Using upsampling + """ + assert(sig1.shape[0] == sig2.shape[0]) + + if sig1.shape[0] % 2 == 1: + sig1 = sig1[:-1] + sig2 = sig2[:-1] + + sig1_up = signal.resample(sig1, sig1.shape[0] * n_up) + sig2_up = signal.resample(sig2, sig2.shape[0] * n_up) + + off_meas = self.lag_upsampling(sig2_up, sig1_up, n_up=1) + off = int(abs(off_meas)) + + if off_meas > 0: + sig1_up = sig1_up[:-off] + sig2_up = sig2_up[off:] + elif off_meas < 0: + sig1_up = sig1_up[off:] + sig2_up = sig2_up[:-off] + + sig1 = signal.resample(sig1_up, sig1_up.shape[0] / n_up).astype(np.complex64) + sig2 = signal.resample(sig2_up, sig2_up.shape[0] / n_up).astype(np.complex64) + return sig1, sig2 + + def subsample_align(self, sig1, sig2): + """ + Returns an aligned version of sig1 and sig2 by cropping and subsample alignment + """ + + if logging.getLogger().getEffectiveLevel() == logging.DEBUG: + dt = datetime.datetime.now().isoformat() + fig_path = logging_path + "/" + dt + "_sync_raw.pdf" + + fig, axs = plt.subplots(2) + axs[0].plot(np.abs(sig1[:128]), label="TX Frame") + axs[0].plot(np.abs(sig2[:128]), label="RX Frame") + axs[0].set_title("Raw Data") + axs[0].set_ylabel("Amplitude") + axs[0].set_xlabel("Samples") + axs[0].legend(loc=4) + + axs[1].plot(np.real(sig1[:128]), label="TX Frame") + axs[1].plot(np.real(sig2[:128]), label="RX Frame") + axs[1].set_title("Raw Data") + axs[1].set_ylabel("Real Part") + axs[1].set_xlabel("Samples") + axs[1].legend(loc=4) + + fig.tight_layout() + fig.savefig(fig_path) + fig.clf() + + logging.debug("Sig1_orig: %d %s, Sig2_orig: %d %s" % (len(sig1), sig1.dtype, len(sig2), sig2.dtype)) + off_meas = self.lag_upsampling(sig2, sig1, n_up=1) + off = int(abs(off_meas)) + + if off_meas > 0: + sig1 = sig1[:-off] + sig2 = sig2[off:] + elif off_meas < 0: + sig1 = sig1[off:] + sig2 = sig2[:-off] + + if off % 2 == 1: + sig1 = sig1[:-1] + sig2 = sig2[:-1] + + if logging.getLogger().getEffectiveLevel() == logging.DEBUG: + dt = datetime.datetime.now().isoformat() + fig_path = logging_path + "/" + dt + "_sync_sample_aligned.pdf" + + fig, axs = plt.subplots(2) + axs[0].plot(np.abs(sig1[:128]), label="TX Frame") + axs[0].plot(np.abs(sig2[:128]), label="RX Frame") + axs[0].set_title("Sample Aligned Data") + axs[0].set_ylabel("Amplitude") + axs[0].set_xlabel("Samples") + axs[0].legend(loc=4) + + axs[1].plot(np.real(sig1[:128]), label="TX Frame") + axs[1].plot(np.real(sig2[:128]), label="RX Frame") + axs[1].set_ylabel("Real Part") + axs[1].set_xlabel("Samples") + axs[1].legend(loc=4) + + fig.tight_layout() + fig.savefig(fig_path) + fig.clf() + + + sig2 = sa.subsample_align(sig2, sig1) + + if logging.getLogger().getEffectiveLevel() == logging.DEBUG: + dt = datetime.datetime.now().isoformat() + fig_path = logging_path + "/" + dt + "_sync_subsample_aligned.pdf" + + fig, axs = plt.subplots(2) + axs[0].plot(np.abs(sig1[:128]), label="TX Frame") + axs[0].plot(np.abs(sig2[:128]), label="RX Frame") + axs[0].set_title("Subsample Aligned") + axs[0].set_ylabel("Amplitude") + axs[0].set_xlabel("Samples") + axs[0].legend(loc=4) + + axs[1].plot(np.real(sig1[:128]), label="TX Frame") + axs[1].plot(np.real(sig2[:128]), label="RX Frame") + axs[1].set_ylabel("Real Part") + axs[1].set_xlabel("Samples") + axs[1].legend(loc=4) + + fig.tight_layout() + fig.savefig(fig_path) + fig.clf() + + sig2 = pa.phase_align(sig2, sig1) + + if logging.getLogger().getEffectiveLevel() == logging.DEBUG: + dt = datetime.datetime.now().isoformat() + fig_path = logging_path + "/" + dt + "_sync_phase_aligned.pdf" + + fig, axs = plt.subplots(2) + axs[0].plot(np.abs(sig1[:128]), label="TX Frame") + axs[0].plot(np.abs(sig2[:128]), label="RX Frame") + axs[0].set_title("Phase Aligned") + axs[0].set_ylabel("Amplitude") + axs[0].set_xlabel("Samples") + axs[0].legend(loc=4) + + axs[1].plot(np.real(sig1[:128]), label="TX Frame") + axs[1].plot(np.real(sig2[:128]), label="RX Frame") + axs[1].set_ylabel("Real Part") + axs[1].set_xlabel("Samples") + axs[1].legend(loc=4) + + fig.tight_layout() + fig.savefig(fig_path) + fig.clf() + + logging.debug("Sig1_cut: %d %s, Sig2_cut: %d %s, off: %d" % (len(sig1), sig1.dtype, len(sig2), sig2.dtype, off)) + return sig1, sig2 + + def fromfile(self, filename, offset=0, length=None): + if length is None: + return np.memmap(filename, dtype=np.complex64, mode='r', offset=64/8*offset) + else: + return np.memmap(filename, dtype=np.complex64, mode='r', offset=64/8*offset, shape=length) + + +# The MIT License (MIT) +# +# Copyright (c) 2017 Andreas Steger +# +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documentation files (the "Software"), to deal +# in the Software without restriction, including without limitation the rights +# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +# copies of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in all +# copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +# SOFTWARE. |