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Diffstat (limited to 'dpd/src/MER.py')
| -rw-r--r-- | dpd/src/MER.py | 132 |
1 files changed, 0 insertions, 132 deletions
diff --git a/dpd/src/MER.py b/dpd/src/MER.py deleted file mode 100644 index 693058d..0000000 --- a/dpd/src/MER.py +++ /dev/null @@ -1,132 +0,0 @@ -# -*- coding: utf-8 -*- -# -# DPD Computation Engine, Modulation Error Rate. -# -# 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 - -class MER: - def __init__(self, c): - self.c = c - - self.plot = c.MER_plot - - def _calc_spectrum(self, tx): - fft = np.fft.fftshift(np.fft.fft(tx)) - return np.delete(fft[self.c.FFT_start:self.c.FFT_end], - self.c.FFT_delete) - - def _split_in_carrier(self, x, y): - if 0.5 < np.mean((np.abs(np.abs(x) - np.abs(y)) / - np.abs(np.abs(x) + np.abs(y)))): - # Constellation points are axis aligned on the Im/Re plane - x1 = x[(y < x) & (y > -x)] - y1 = y[(y < x) & (y > -x)] - - x2 = x[(y > x) & (y > -x)] - y2 = y[(y > x) & (y > -x)] - - x3 = x[(y > x) & (y < -x)] - y3 = y[(y > x) & (y < -x)] - - x4 = x[(y < x) & (y < -x)] - y4 = y[(y < x) & (y < -x)] - else: - # Constellation points are on the diagonal or Im/Re plane - x1 = x[(+x > 0) & (+y > 0)] - y1 = y[(+x > 0) & (+y > 0)] - - x2 = x[(-x > 0) & (+y > 0)] - y2 = y[(-x > 0) & (+y > 0)] - - x3 = x[(-x > 0) & (-y > 0)] - y3 = y[(-x > 0) & (-y > 0)] - - x4 = x[(+x > 0) & (-y > 0)] - y4 = y[(+x > 0) & (-y > 0)] - return (x1, y1), (x2, y2), (x3, y3), (x4, y4) - - def _calc_mer_for_isolated_constellation_point(self, x, y): - """Calculate MER for one constellation point""" - x_mean = np.mean(x) - y_mean = np.mean(y) - - U_RMS = np.sqrt(x_mean ** 2 + y_mean ** 2) - U_ERR = np.mean(np.sqrt((x - x_mean) ** 2 + (y - y_mean) ** 2)) - MER = 20 * np.log10(U_ERR / U_RMS) - - return x_mean, y_mean, U_RMS, U_ERR, MER - - def calc_mer(self, tx, debug_name=""): - """Calculate MER for input signal from a symbol aligned signal.""" - assert tx.shape[0] == self.c.T_U, "Wrong input length" - - spectrum = self._calc_spectrum(tx) - - if self.plot and self.c.plot_location is not None: - dt = datetime.datetime.now().isoformat() - fig_path = self.c.plot_location + "/" + dt + "_MER" + debug_name + ".png" - else: - fig_path = None - - MERs = [] - for i, (x, y) in enumerate(self._split_in_carrier( - np.real(spectrum), - np.imag(spectrum))): - x_mean, y_mean, U_RMS, U_ERR, MER =\ - self._calc_mer_for_isolated_constellation_point(x, y) - MERs.append(MER) - - tau = np.linspace(0, 2 * np.pi, num=100) - x_err = U_ERR * np.sin(tau) + x_mean - y_err = U_ERR * np.cos(tau) + y_mean - - if self.plot: - ax = plt.subplot(221 + i) - ax.scatter(x, y, s=0.2, color='black') - ax.plot(x_mean, y_mean, 'p', color='red') - ax.plot(x_err, y_err, linewidth=2, color='blue') - ax.text(0.1, 0.1, "MER {:.1f}dB".format(MER), transform=ax.transAxes) - ax.set_xlabel("Real") - ax.set_ylabel("Imag") - ylim = ax.get_ylim() - ax.set_ylim(ylim[0] - (ylim[1] - ylim[0]) * 0.1, ylim[1]) - - if fig_path is not None: - plt.tight_layout() - plt.savefig(fig_path) - plt.show() - plt.close() - - MER_res = 20 * np.log10(np.mean([10 ** (MER / 20) for MER in MERs])) - return MER_res - -# 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. |