Move python stuff to folder

1 files changed, 246 insertions, 0 deletions

diff --git a/python/dpd/src/Dab_Util.py b/python/dpd/src/Dab_Util.py
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+# -*- coding: utf-8 -*-
+#
+# DPD Computation Engine, utilities for working with DAB signals.
+#
+# http://www.opendigitalradio.org
+# Licence: The MIT License, see notice at the end of this file
+
+import datetime
+import os
+import logging
+import numpy as np
+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
+
+
+def fromfile(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)
+
+
+class Dab_Util:
+    """Collection of methods that can be applied to an array
+     complex IQ samples of a DAB signal
+     """
+
+    def __init__(self, config, sample_rate, plot=False):
+        """
+        :param sample_rate: sample rate [sample/sec] to use for calculations
+        """
+        self.c = config
+        self.sample_rate = sample_rate
+        self.dab_bandwidth = 1536000  # Bandwidth of a dab signal
+        self.frame_ms = 96  # Duration of a Dab frame
+
+        self.plot = plot
+
+    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 self.plot and self.c.plot_location is not None:
+            dt = datetime.datetime.now().isoformat()
+            corr_path = self.c.plot_location + "/" + dt + "_tx_rx_corr.png"
+            plt.plot(c, label="corr")
+            plt.legend()
+            plt.savefig(corr_path)
+            plt.close()
+
+        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, sig_tx, sig_rx, n_up=32):
+        """
+        Returns an aligned version of sig_tx and sig_rx by cropping and subsample alignment
+        Using upsampling
+        """
+        assert (sig_tx.shape[0] == sig_rx.shape[0])
+
+        if sig_tx.shape[0] % 2 == 1:
+            sig_tx = sig_tx[:-1]
+            sig_rx = sig_rx[:-1]
+
+        sig1_up = signal.resample(sig_tx, sig_tx.shape[0] * n_up)
+        sig2_up = signal.resample(sig_rx, sig_rx.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]
+
+        sig_tx = signal.resample(sig1_up, sig1_up.shape[0] / n_up).astype(np.complex64)
+        sig_rx = signal.resample(sig2_up, sig2_up.shape[0] / n_up).astype(np.complex64)
+        return sig_tx, sig_rx
+
+    def subsample_align(self, sig_tx, sig_rx):
+        """
+        Returns an aligned version of sig_tx and sig_rx by cropping and subsample alignment
+        """
+
+        if self.plot and self.c.plot_location is not None:
+            dt = datetime.datetime.now().isoformat()
+            fig_path = self.c.plot_location + "/" + dt + "_sync_raw.png"
+
+            fig, axs = plt.subplots(2)
+            axs[0].plot(np.abs(sig_tx[:128]), label="TX Frame")
+            axs[0].plot(np.abs(sig_rx[: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(sig_tx[:128]), label="TX Frame")
+            axs[1].plot(np.real(sig_rx[: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)
+            plt.close(fig)
+
+        off_meas = self.lag_upsampling(sig_rx, sig_tx, n_up=1)
+        off = int(abs(off_meas))
+
+        logging.debug("sig_tx_orig: {} {}, sig_rx_orig: {} {}, offset {}".format(
+            len(sig_tx),
+            sig_tx.dtype,
+            len(sig_rx),
+            sig_rx.dtype,
+            off_meas))
+
+        if off_meas > 0:
+            sig_tx = sig_tx[:-off]
+            sig_rx = sig_rx[off:]
+        elif off_meas < 0:
+            sig_tx = sig_tx[off:]
+            sig_rx = sig_rx[:-off]
+
+        if off % 2 == 1:
+            sig_tx = sig_tx[:-1]
+            sig_rx = sig_rx[:-1]
+
+        if self.plot and self.c.plot_location is not None:
+            dt = datetime.datetime.now().isoformat()
+            fig_path = self.c.plot_location + "/" + dt + "_sync_sample_aligned.png"
+
+            fig, axs = plt.subplots(2)
+            axs[0].plot(np.abs(sig_tx[:128]), label="TX Frame")
+            axs[0].plot(np.abs(sig_rx[: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(sig_tx[:128]), label="TX Frame")
+            axs[1].plot(np.real(sig_rx[: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)
+            plt.close(fig)
+
+        sig_rx = sa.subsample_align(sig_rx, sig_tx)
+
+        if self.plot and self.c.plot_location is not None:
+            dt = datetime.datetime.now().isoformat()
+            fig_path = self.c.plot_location + "/" + dt + "_sync_subsample_aligned.png"
+
+            fig, axs = plt.subplots(2)
+            axs[0].plot(np.abs(sig_tx[:128]), label="TX Frame")
+            axs[0].plot(np.abs(sig_rx[: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(sig_tx[:128]), label="TX Frame")
+            axs[1].plot(np.real(sig_rx[: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)
+            plt.close(fig)
+
+        sig_rx = pa.phase_align(sig_rx, sig_tx)
+
+        if self.plot and self.c.plot_location is not None:
+            dt = datetime.datetime.now().isoformat()
+            fig_path = self.c.plot_location + "/" + dt + "_sync_phase_aligned.png"
+
+            fig, axs = plt.subplots(2)
+            axs[0].plot(np.abs(sig_tx[:128]), label="TX Frame")
+            axs[0].plot(np.abs(sig_rx[: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(sig_tx[:128]), label="TX Frame")
+            axs[1].plot(np.real(sig_rx[: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)
+            plt.close(fig)
+
+        logging.debug(
+            "Sig1_cut: %d %s, Sig2_cut: %d %s, off: %d" % (len(sig_tx), sig_tx.dtype, len(sig_rx), sig_rx.dtype, off))
+        return sig_tx, sig_rx
+
+# 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.