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P25 LSM decoder work in progress. Adds a CQPSK decoder based on Max's (KA1RBI) scope.py and gardner loop.

Browse Source 
The CQPSK decoder is starting to take shape, but needs more tweaking and testing.  It's not keeping a good lock on strong P25 signals.  I have to add some more features to the intrumentation package to allow me to visualize the internals of the CQPSK decoder so that I can get a better sense of what needs fine tuning.

The CQPSK decoder may work for anyone that wants to sync the repo and run the build script.
This commit is contained in:
dennis.sheirer
2015-02-10 00:42:08 +00:00
parent 9310fb0daf
commit a65e821e85
43 changed files with 1996 additions and 413 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
src/dsp/am/AMDemodulator.java
View File

@@ -18,8 +18,8 @@ public class AMDemodulator implements Listener<ComplexSample>, RealSampleProvide
{
float demodulated = (float)Math.sqrt( ( sample.real() *
sample.real() ) +
( sample.imaginery() *
sample.imaginery() ) );
( sample.imaginary() *
sample.imaginary() ) );
if( mListener != null )
{

98
src/dsp/filter/FilterFactory.java
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@@ -1,7 +1,12 @@
/*******************************************************************************
* SDR Trunk
* Copyright (C) 2014 Dennis Sheirer
*
* Copyright (C) 2014,2015 Dennis Sheirer
*
* Root Raised Cosine filter designer:
* Copyright 2002,2007,2008,2012,2013 Free Software Foundation, Inc.
* http://gnuradio.org/redmine/projects/gnuradio/repository/changes/gr-filter
* /lib/firdes.cc?rev=435b1d166f0c7092bbd5e1f788e75dbb6ade3a4b
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
@@ -727,4 +732,93 @@ public class FilterFactory
return cicArray;
}
/**
* Creates root raised cosine filter coefficients.
*
* Ported to java from gnuradio/filter/firdes.cc
*
* @param gain - gain value to apply
* @param sampleRate - sample rate in hertz
* @param symbolRate - symbol rate in hertz
* @param alpha - roll-off factor
* @param tapCount - odd number of taps, or will be increased to make odd
* @return - filter coefficients
*/
public static double[] getRootRaisedCosine( double gain,
double sampleRate,
double symbolRate,
double alpha,
int tapCount )
{
/* Ensure odd number of taps */
int taps = tapCount | 1;
double scale = 0;
double samplesPerSymbol = sampleRate / symbolRate;
double[] coefficients = new double[ taps ];
for( int x = 0; x < taps; x++ )
{
double index = x - ( taps / 2 );
double x1 = Math.PI * index / samplesPerSymbol;
double x2 = 4.0 * alpha * index / samplesPerSymbol;
double x3 = x2 * x2 - 1;
double numerator, denominator;
if( Math.abs( x3 ) >= 0.000001 )
{
if( x != taps / 2 )
{
numerator = Math.cos( ( 1.0 + alpha ) * x1 ) +
Math.sin( ( 1.0 - alpha ) * x1 ) /
( 4.0 * alpha * index / samplesPerSymbol );
}
else
{
numerator = Math.cos( ( 1.0 + alpha ) * x1 ) +
( 1.0 - alpha ) * Math.PI / ( 4.0 * alpha );
}
denominator = x3 * Math.PI;
}
else
{
if( alpha == 1.0 )
{
coefficients[ x ] = -1.0;
continue;
}
x3 = ( 1.0 - alpha ) * x1;
x2 = ( 1.0 + alpha ) * x1;
numerator = ( Math.sin( x2 ) * ( 1.0 + alpha ) * Math.PI -
Math.cos( x3 ) * ( ( 1.0 - alpha ) * Math.PI * samplesPerSymbol ) /
( 4 * alpha * index ) +
Math.sin( x3 ) * samplesPerSymbol * samplesPerSymbol /
( 4.0 * alpha * index * index ) );
denominator = -32.0 * Math.PI * alpha * alpha * index / samplesPerSymbol;
}
coefficients[ x ] = 4.0 * alpha * numerator / denominator;
scale += coefficients[ x ];
}
/**
* Normalize (scale) coefficients to 1.0 sum and apply gain
*/
for( int x = 0; x < taps; x++ )
{
coefficients[ x ] = coefficients[ x ] * gain / scale;
}
return coefficients;
}
}

161
src/dsp/filter/interpolator/Interpolator.java Normal file
View File

@@ -0,0 +1,161 @@
package dsp.filter.interpolator;
/*******************************************************************************
* SDR Trunk
* Copyright (C) 2015 Dennis Sheirer
*
* Copyright (C) 2002,2012 Free Software Foundation, Inc.
* Ported to java from gnuradio - interpolator_taps.h
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>
******************************************************************************/
public abstract class Interpolator
{
public static final int NTAPS = 8;
public static final int NSTEPS = 128;
public static final float TAPS[][] = new float[][]
{
// -4 -3 -2 -1 0 1 2 3 mu
{ 0.00000e+00f, 0.00000e+00f, 0.00000e+00f, 0.00000e+00f, 1.00000e+00f, 0.00000e+00f, 0.00000e+00f, 0.00000e+00f }, // 0/128
{ -1.54700e-04f, 8.53777e-04f, -2.76968e-03f, 7.89295e-03f, 9.98534e-01f, -5.41054e-03f, 1.24642e-03f, -1.98993e-04f }, // 1/128
{ -3.09412e-04f, 1.70888e-03f, -5.55134e-03f, 1.58840e-02f, 9.96891e-01f, -1.07209e-02f, 2.47942e-03f, -3.96391e-04f }, // 2/128
{ -4.64053e-04f, 2.56486e-03f, -8.34364e-03f, 2.39714e-02f, 9.95074e-01f, -1.59305e-02f, 3.69852e-03f, -5.92100e-04f }, // 3/128
{ -6.18544e-04f, 3.42130e-03f, -1.11453e-02f, 3.21531e-02f, 9.93082e-01f, -2.10389e-02f, 4.90322e-03f, -7.86031e-04f }, // 4/128
{ -7.72802e-04f, 4.27773e-03f, -1.39548e-02f, 4.04274e-02f, 9.90917e-01f, -2.60456e-02f, 6.09305e-03f, -9.78093e-04f }, // 5/128
{ -9.26747e-04f, 5.13372e-03f, -1.67710e-02f, 4.87921e-02f, 9.88580e-01f, -3.09503e-02f, 7.26755e-03f, -1.16820e-03f }, // 6/128
{ -1.08030e-03f, 5.98883e-03f, -1.95925e-02f, 5.72454e-02f, 9.86071e-01f, -3.57525e-02f, 8.42626e-03f, -1.35627e-03f }, // 7/128
{ -1.23337e-03f, 6.84261e-03f, -2.24178e-02f, 6.57852e-02f, 9.83392e-01f, -4.04519e-02f, 9.56876e-03f, -1.54221e-03f }, // 8/128
{ -1.38589e-03f, 7.69462e-03f, -2.52457e-02f, 7.44095e-02f, 9.80543e-01f, -4.50483e-02f, 1.06946e-02f, -1.72594e-03f }, // 9/128
{ -1.53777e-03f, 8.54441e-03f, -2.80746e-02f, 8.31162e-02f, 9.77526e-01f, -4.95412e-02f, 1.18034e-02f, -1.90738e-03f }, // 10/128
{ -1.68894e-03f, 9.39154e-03f, -3.09033e-02f, 9.19033e-02f, 9.74342e-01f, -5.39305e-02f, 1.28947e-02f, -2.08645e-03f }, // 11/128
{ -1.83931e-03f, 1.02356e-02f, -3.37303e-02f, 1.00769e-01f, 9.70992e-01f, -5.82159e-02f, 1.39681e-02f, -2.26307e-03f }, // 12/128
{ -1.98880e-03f, 1.10760e-02f, -3.65541e-02f, 1.09710e-01f, 9.67477e-01f, -6.23972e-02f, 1.50233e-02f, -2.43718e-03f }, // 13/128
{ -2.13733e-03f, 1.19125e-02f, -3.93735e-02f, 1.18725e-01f, 9.63798e-01f, -6.64743e-02f, 1.60599e-02f, -2.60868e-03f }, // 14/128
{ -2.28483e-03f, 1.27445e-02f, -4.21869e-02f, 1.27812e-01f, 9.59958e-01f, -7.04471e-02f, 1.70776e-02f, -2.77751e-03f }, // 15/128
{ -2.43121e-03f, 1.35716e-02f, -4.49929e-02f, 1.36968e-01f, 9.55956e-01f, -7.43154e-02f, 1.80759e-02f, -2.94361e-03f }, // 16/128
{ -2.57640e-03f, 1.43934e-02f, -4.77900e-02f, 1.46192e-01f, 9.51795e-01f, -7.80792e-02f, 1.90545e-02f, -3.10689e-03f }, // 17/128
{ -2.72032e-03f, 1.52095e-02f, -5.05770e-02f, 1.55480e-01f, 9.47477e-01f, -8.17385e-02f, 2.00132e-02f, -3.26730e-03f }, // 18/128
{ -2.86289e-03f, 1.60193e-02f, -5.33522e-02f, 1.64831e-01f, 9.43001e-01f, -8.52933e-02f, 2.09516e-02f, -3.42477e-03f }, // 19/128
{ -3.00403e-03f, 1.68225e-02f, -5.61142e-02f, 1.74242e-01f, 9.38371e-01f, -8.87435e-02f, 2.18695e-02f, -3.57923e-03f }, // 20/128
{ -3.14367e-03f, 1.76185e-02f, -5.88617e-02f, 1.83711e-01f, 9.33586e-01f, -9.20893e-02f, 2.27664e-02f, -3.73062e-03f }, // 21/128
{ -3.28174e-03f, 1.84071e-02f, -6.15931e-02f, 1.93236e-01f, 9.28650e-01f, -9.53307e-02f, 2.36423e-02f, -3.87888e-03f }, // 22/128
{ -3.41815e-03f, 1.91877e-02f, -6.43069e-02f, 2.02814e-01f, 9.23564e-01f, -9.84679e-02f, 2.44967e-02f, -4.02397e-03f }, // 23/128
{ -3.55283e-03f, 1.99599e-02f, -6.70018e-02f, 2.12443e-01f, 9.18329e-01f, -1.01501e-01f, 2.53295e-02f, -4.16581e-03f }, // 24/128
{ -3.68570e-03f, 2.07233e-02f, -6.96762e-02f, 2.22120e-01f, 9.12947e-01f, -1.04430e-01f, 2.61404e-02f, -4.30435e-03f }, // 25/128
{ -3.81671e-03f, 2.14774e-02f, -7.23286e-02f, 2.31843e-01f, 9.07420e-01f, -1.07256e-01f, 2.69293e-02f, -4.43955e-03f }, // 26/128
{ -3.94576e-03f, 2.22218e-02f, -7.49577e-02f, 2.41609e-01f, 9.01749e-01f, -1.09978e-01f, 2.76957e-02f, -4.57135e-03f }, // 27/128
{ -4.07279e-03f, 2.29562e-02f, -7.75620e-02f, 2.51417e-01f, 8.95936e-01f, -1.12597e-01f, 2.84397e-02f, -4.69970e-03f }, // 28/128
{ -4.19774e-03f, 2.36801e-02f, -8.01399e-02f, 2.61263e-01f, 8.89984e-01f, -1.15113e-01f, 2.91609e-02f, -4.82456e-03f }, // 29/128
{ -4.32052e-03f, 2.43930e-02f, -8.26900e-02f, 2.71144e-01f, 8.83893e-01f, -1.17526e-01f, 2.98593e-02f, -4.94589e-03f }, // 30/128
{ -4.44107e-03f, 2.50946e-02f, -8.52109e-02f, 2.81060e-01f, 8.77666e-01f, -1.19837e-01f, 3.05345e-02f, -5.06363e-03f }, // 31/128
{ -4.55932e-03f, 2.57844e-02f, -8.77011e-02f, 2.91006e-01f, 8.71305e-01f, -1.22047e-01f, 3.11866e-02f, -5.17776e-03f }, // 32/128
{ -4.67520e-03f, 2.64621e-02f, -9.01591e-02f, 3.00980e-01f, 8.64812e-01f, -1.24154e-01f, 3.18153e-02f, -5.28823e-03f }, // 33/128
{ -4.78866e-03f, 2.71272e-02f, -9.25834e-02f, 3.10980e-01f, 8.58189e-01f, -1.26161e-01f, 3.24205e-02f, -5.39500e-03f }, // 34/128
{ -4.89961e-03f, 2.77794e-02f, -9.49727e-02f, 3.21004e-01f, 8.51437e-01f, -1.28068e-01f, 3.30021e-02f, -5.49804e-03f }, // 35/128
{ -5.00800e-03f, 2.84182e-02f, -9.73254e-02f, 3.31048e-01f, 8.44559e-01f, -1.29874e-01f, 3.35600e-02f, -5.59731e-03f }, // 36/128
{ -5.11376e-03f, 2.90433e-02f, -9.96402e-02f, 3.41109e-01f, 8.37557e-01f, -1.31581e-01f, 3.40940e-02f, -5.69280e-03f }, // 37/128
{ -5.21683e-03f, 2.96543e-02f, -1.01915e-01f, 3.51186e-01f, 8.30432e-01f, -1.33189e-01f, 3.46042e-02f, -5.78446e-03f }, // 38/128
{ -5.31716e-03f, 3.02507e-02f, -1.04150e-01f, 3.61276e-01f, 8.23188e-01f, -1.34699e-01f, 3.50903e-02f, -5.87227e-03f }, // 39/128
{ -5.41467e-03f, 3.08323e-02f, -1.06342e-01f, 3.71376e-01f, 8.15826e-01f, -1.36111e-01f, 3.55525e-02f, -5.95620e-03f }, // 40/128
{ -5.50931e-03f, 3.13987e-02f, -1.08490e-01f, 3.81484e-01f, 8.08348e-01f, -1.37426e-01f, 3.59905e-02f, -6.03624e-03f }, // 41/128
{ -5.60103e-03f, 3.19495e-02f, -1.10593e-01f, 3.91596e-01f, 8.00757e-01f, -1.38644e-01f, 3.64044e-02f, -6.11236e-03f }, // 42/128
{ -5.68976e-03f, 3.24843e-02f, -1.12650e-01f, 4.01710e-01f, 7.93055e-01f, -1.39767e-01f, 3.67941e-02f, -6.18454e-03f }, // 43/128
{ -5.77544e-03f, 3.30027e-02f, -1.14659e-01f, 4.11823e-01f, 7.85244e-01f, -1.40794e-01f, 3.71596e-02f, -6.25277e-03f }, // 44/128
{ -5.85804e-03f, 3.35046e-02f, -1.16618e-01f, 4.21934e-01f, 7.77327e-01f, -1.41727e-01f, 3.75010e-02f, -6.31703e-03f }, // 45/128
{ -5.93749e-03f, 3.39894e-02f, -1.18526e-01f, 4.32038e-01f, 7.69305e-01f, -1.42566e-01f, 3.78182e-02f, -6.37730e-03f }, // 46/128
{ -6.01374e-03f, 3.44568e-02f, -1.20382e-01f, 4.42134e-01f, 7.61181e-01f, -1.43313e-01f, 3.81111e-02f, -6.43358e-03f }, // 47/128
{ -6.08674e-03f, 3.49066e-02f, -1.22185e-01f, 4.52218e-01f, 7.52958e-01f, -1.43968e-01f, 3.83800e-02f, -6.48585e-03f }, // 48/128
{ -6.15644e-03f, 3.53384e-02f, -1.23933e-01f, 4.62289e-01f, 7.44637e-01f, -1.44531e-01f, 3.86247e-02f, -6.53412e-03f }, // 49/128
{ -6.22280e-03f, 3.57519e-02f, -1.25624e-01f, 4.72342e-01f, 7.36222e-01f, -1.45004e-01f, 3.88454e-02f, -6.57836e-03f }, // 50/128
{ -6.28577e-03f, 3.61468e-02f, -1.27258e-01f, 4.82377e-01f, 7.27714e-01f, -1.45387e-01f, 3.90420e-02f, -6.61859e-03f }, // 51/128
{ -6.34530e-03f, 3.65227e-02f, -1.28832e-01f, 4.92389e-01f, 7.19116e-01f, -1.45682e-01f, 3.92147e-02f, -6.65479e-03f }, // 52/128
{ -6.40135e-03f, 3.68795e-02f, -1.30347e-01f, 5.02377e-01f, 7.10431e-01f, -1.45889e-01f, 3.93636e-02f, -6.68698e-03f }, // 53/128
{ -6.45388e-03f, 3.72167e-02f, -1.31800e-01f, 5.12337e-01f, 7.01661e-01f, -1.46009e-01f, 3.94886e-02f, -6.71514e-03f }, // 54/128
{ -6.50285e-03f, 3.75341e-02f, -1.33190e-01f, 5.22267e-01f, 6.92808e-01f, -1.46043e-01f, 3.95900e-02f, -6.73929e-03f }, // 55/128
{ -6.54823e-03f, 3.78315e-02f, -1.34515e-01f, 5.32164e-01f, 6.83875e-01f, -1.45993e-01f, 3.96678e-02f, -6.75943e-03f }, // 56/128
{ -6.58996e-03f, 3.81085e-02f, -1.35775e-01f, 5.42025e-01f, 6.74865e-01f, -1.45859e-01f, 3.97222e-02f, -6.77557e-03f }, // 57/128
{ -6.62802e-03f, 3.83650e-02f, -1.36969e-01f, 5.51849e-01f, 6.65779e-01f, -1.45641e-01f, 3.97532e-02f, -6.78771e-03f }, // 58/128
{ -6.66238e-03f, 3.86006e-02f, -1.38094e-01f, 5.61631e-01f, 6.56621e-01f, -1.45343e-01f, 3.97610e-02f, -6.79588e-03f }, // 59/128
{ -6.69300e-03f, 3.88151e-02f, -1.39150e-01f, 5.71370e-01f, 6.47394e-01f, -1.44963e-01f, 3.97458e-02f, -6.80007e-03f }, // 60/128
{ -6.71985e-03f, 3.90083e-02f, -1.40136e-01f, 5.81063e-01f, 6.38099e-01f, -1.44503e-01f, 3.97077e-02f, -6.80032e-03f }, // 61/128
{ -6.74291e-03f, 3.91800e-02f, -1.41050e-01f, 5.90706e-01f, 6.28739e-01f, -1.43965e-01f, 3.96469e-02f, -6.79662e-03f }, // 62/128
{ -6.76214e-03f, 3.93299e-02f, -1.41891e-01f, 6.00298e-01f, 6.19318e-01f, -1.43350e-01f, 3.95635e-02f, -6.78902e-03f }, // 63/128
{ -6.77751e-03f, 3.94578e-02f, -1.42658e-01f, 6.09836e-01f, 6.09836e-01f, -1.42658e-01f, 3.94578e-02f, -6.77751e-03f }, // 64/128
{ -6.78902e-03f, 3.95635e-02f, -1.43350e-01f, 6.19318e-01f, 6.00298e-01f, -1.41891e-01f, 3.93299e-02f, -6.76214e-03f }, // 65/128
{ -6.79662e-03f, 3.96469e-02f, -1.43965e-01f, 6.28739e-01f, 5.90706e-01f, -1.41050e-01f, 3.91800e-02f, -6.74291e-03f }, // 66/128
{ -6.80032e-03f, 3.97077e-02f, -1.44503e-01f, 6.38099e-01f, 5.81063e-01f, -1.40136e-01f, 3.90083e-02f, -6.71985e-03f }, // 67/128
{ -6.80007e-03f, 3.97458e-02f, -1.44963e-01f, 6.47394e-01f, 5.71370e-01f, -1.39150e-01f, 3.88151e-02f, -6.69300e-03f }, // 68/128
{ -6.79588e-03f, 3.97610e-02f, -1.45343e-01f, 6.56621e-01f, 5.61631e-01f, -1.38094e-01f, 3.86006e-02f, -6.66238e-03f }, // 69/128
{ -6.78771e-03f, 3.97532e-02f, -1.45641e-01f, 6.65779e-01f, 5.51849e-01f, -1.36969e-01f, 3.83650e-02f, -6.62802e-03f }, // 70/128
{ -6.77557e-03f, 3.97222e-02f, -1.45859e-01f, 6.74865e-01f, 5.42025e-01f, -1.35775e-01f, 3.81085e-02f, -6.58996e-03f }, // 71/128
{ -6.75943e-03f, 3.96678e-02f, -1.45993e-01f, 6.83875e-01f, 5.32164e-01f, -1.34515e-01f, 3.78315e-02f, -6.54823e-03f }, // 72/128
{ -6.73929e-03f, 3.95900e-02f, -1.46043e-01f, 6.92808e-01f, 5.22267e-01f, -1.33190e-01f, 3.75341e-02f, -6.50285e-03f }, // 73/128
{ -6.71514e-03f, 3.94886e-02f, -1.46009e-01f, 7.01661e-01f, 5.12337e-01f, -1.31800e-01f, 3.72167e-02f, -6.45388e-03f }, // 74/128
{ -6.68698e-03f, 3.93636e-02f, -1.45889e-01f, 7.10431e-01f, 5.02377e-01f, -1.30347e-01f, 3.68795e-02f, -6.40135e-03f }, // 75/128
{ -6.65479e-03f, 3.92147e-02f, -1.45682e-01f, 7.19116e-01f, 4.92389e-01f, -1.28832e-01f, 3.65227e-02f, -6.34530e-03f }, // 76/128
{ -6.61859e-03f, 3.90420e-02f, -1.45387e-01f, 7.27714e-01f, 4.82377e-01f, -1.27258e-01f, 3.61468e-02f, -6.28577e-03f }, // 77/128
{ -6.57836e-03f, 3.88454e-02f, -1.45004e-01f, 7.36222e-01f, 4.72342e-01f, -1.25624e-01f, 3.57519e-02f, -6.22280e-03f }, // 78/128
{ -6.53412e-03f, 3.86247e-02f, -1.44531e-01f, 7.44637e-01f, 4.62289e-01f, -1.23933e-01f, 3.53384e-02f, -6.15644e-03f }, // 79/128
{ -6.48585e-03f, 3.83800e-02f, -1.43968e-01f, 7.52958e-01f, 4.52218e-01f, -1.22185e-01f, 3.49066e-02f, -6.08674e-03f }, // 80/128
{ -6.43358e-03f, 3.81111e-02f, -1.43313e-01f, 7.61181e-01f, 4.42134e-01f, -1.20382e-01f, 3.44568e-02f, -6.01374e-03f }, // 81/128
{ -6.37730e-03f, 3.78182e-02f, -1.42566e-01f, 7.69305e-01f, 4.32038e-01f, -1.18526e-01f, 3.39894e-02f, -5.93749e-03f }, // 82/128
{ -6.31703e-03f, 3.75010e-02f, -1.41727e-01f, 7.77327e-01f, 4.21934e-01f, -1.16618e-01f, 3.35046e-02f, -5.85804e-03f }, // 83/128
{ -6.25277e-03f, 3.71596e-02f, -1.40794e-01f, 7.85244e-01f, 4.11823e-01f, -1.14659e-01f, 3.30027e-02f, -5.77544e-03f }, // 84/128
{ -6.18454e-03f, 3.67941e-02f, -1.39767e-01f, 7.93055e-01f, 4.01710e-01f, -1.12650e-01f, 3.24843e-02f, -5.68976e-03f }, // 85/128
{ -6.11236e-03f, 3.64044e-02f, -1.38644e-01f, 8.00757e-01f, 3.91596e-01f, -1.10593e-01f, 3.19495e-02f, -5.60103e-03f }, // 86/128
{ -6.03624e-03f, 3.59905e-02f, -1.37426e-01f, 8.08348e-01f, 3.81484e-01f, -1.08490e-01f, 3.13987e-02f, -5.50931e-03f }, // 87/128
{ -5.95620e-03f, 3.55525e-02f, -1.36111e-01f, 8.15826e-01f, 3.71376e-01f, -1.06342e-01f, 3.08323e-02f, -5.41467e-03f }, // 88/128
{ -5.87227e-03f, 3.50903e-02f, -1.34699e-01f, 8.23188e-01f, 3.61276e-01f, -1.04150e-01f, 3.02507e-02f, -5.31716e-03f }, // 89/128
{ -5.78446e-03f, 3.46042e-02f, -1.33189e-01f, 8.30432e-01f, 3.51186e-01f, -1.01915e-01f, 2.96543e-02f, -5.21683e-03f }, // 90/128
{ -5.69280e-03f, 3.40940e-02f, -1.31581e-01f, 8.37557e-01f, 3.41109e-01f, -9.96402e-02f, 2.90433e-02f, -5.11376e-03f }, // 91/128
{ -5.59731e-03f, 3.35600e-02f, -1.29874e-01f, 8.44559e-01f, 3.31048e-01f, -9.73254e-02f, 2.84182e-02f, -5.00800e-03f }, // 92/128
{ -5.49804e-03f, 3.30021e-02f, -1.28068e-01f, 8.51437e-01f, 3.21004e-01f, -9.49727e-02f, 2.77794e-02f, -4.89961e-03f }, // 93/128
{ -5.39500e-03f, 3.24205e-02f, -1.26161e-01f, 8.58189e-01f, 3.10980e-01f, -9.25834e-02f, 2.71272e-02f, -4.78866e-03f }, // 94/128
{ -5.28823e-03f, 3.18153e-02f, -1.24154e-01f, 8.64812e-01f, 3.00980e-01f, -9.01591e-02f, 2.64621e-02f, -4.67520e-03f }, // 95/128
{ -5.17776e-03f, 3.11866e-02f, -1.22047e-01f, 8.71305e-01f, 2.91006e-01f, -8.77011e-02f, 2.57844e-02f, -4.55932e-03f }, // 96/128
{ -5.06363e-03f, 3.05345e-02f, -1.19837e-01f, 8.77666e-01f, 2.81060e-01f, -8.52109e-02f, 2.50946e-02f, -4.44107e-03f }, // 97/128
{ -4.94589e-03f, 2.98593e-02f, -1.17526e-01f, 8.83893e-01f, 2.71144e-01f, -8.26900e-02f, 2.43930e-02f, -4.32052e-03f }, // 98/128
{ -4.82456e-03f, 2.91609e-02f, -1.15113e-01f, 8.89984e-01f, 2.61263e-01f, -8.01399e-02f, 2.36801e-02f, -4.19774e-03f }, // 99/128
{ -4.69970e-03f, 2.84397e-02f, -1.12597e-01f, 8.95936e-01f, 2.51417e-01f, -7.75620e-02f, 2.29562e-02f, -4.07279e-03f }, // 100/128
{ -4.57135e-03f, 2.76957e-02f, -1.09978e-01f, 9.01749e-01f, 2.41609e-01f, -7.49577e-02f, 2.22218e-02f, -3.94576e-03f }, // 101/128
{ -4.43955e-03f, 2.69293e-02f, -1.07256e-01f, 9.07420e-01f, 2.31843e-01f, -7.23286e-02f, 2.14774e-02f, -3.81671e-03f }, // 102/128
{ -4.30435e-03f, 2.61404e-02f, -1.04430e-01f, 9.12947e-01f, 2.22120e-01f, -6.96762e-02f, 2.07233e-02f, -3.68570e-03f }, // 103/128
{ -4.16581e-03f, 2.53295e-02f, -1.01501e-01f, 9.18329e-01f, 2.12443e-01f, -6.70018e-02f, 1.99599e-02f, -3.55283e-03f }, // 104/128
{ -4.02397e-03f, 2.44967e-02f, -9.84679e-02f, 9.23564e-01f, 2.02814e-01f, -6.43069e-02f, 1.91877e-02f, -3.41815e-03f }, // 105/128
{ -3.87888e-03f, 2.36423e-02f, -9.53307e-02f, 9.28650e-01f, 1.93236e-01f, -6.15931e-02f, 1.84071e-02f, -3.28174e-03f }, // 106/128
{ -3.73062e-03f, 2.27664e-02f, -9.20893e-02f, 9.33586e-01f, 1.83711e-01f, -5.88617e-02f, 1.76185e-02f, -3.14367e-03f }, // 107/128
{ -3.57923e-03f, 2.18695e-02f, -8.87435e-02f, 9.38371e-01f, 1.74242e-01f, -5.61142e-02f, 1.68225e-02f, -3.00403e-03f }, // 108/128
{ -3.42477e-03f, 2.09516e-02f, -8.52933e-02f, 9.43001e-01f, 1.64831e-01f, -5.33522e-02f, 1.60193e-02f, -2.86289e-03f }, // 109/128
{ -3.26730e-03f, 2.00132e-02f, -8.17385e-02f, 9.47477e-01f, 1.55480e-01f, -5.05770e-02f, 1.52095e-02f, -2.72032e-03f }, // 110/128
{ -3.10689e-03f, 1.90545e-02f, -7.80792e-02f, 9.51795e-01f, 1.46192e-01f, -4.77900e-02f, 1.43934e-02f, -2.57640e-03f }, // 111/128
{ -2.94361e-03f, 1.80759e-02f, -7.43154e-02f, 9.55956e-01f, 1.36968e-01f, -4.49929e-02f, 1.35716e-02f, -2.43121e-03f }, // 112/128
{ -2.77751e-03f, 1.70776e-02f, -7.04471e-02f, 9.59958e-01f, 1.27812e-01f, -4.21869e-02f, 1.27445e-02f, -2.28483e-03f }, // 113/128
{ -2.60868e-03f, 1.60599e-02f, -6.64743e-02f, 9.63798e-01f, 1.18725e-01f, -3.93735e-02f, 1.19125e-02f, -2.13733e-03f }, // 114/128
{ -2.43718e-03f, 1.50233e-02f, -6.23972e-02f, 9.67477e-01f, 1.09710e-01f, -3.65541e-02f, 1.10760e-02f, -1.98880e-03f }, // 115/128
{ -2.26307e-03f, 1.39681e-02f, -5.82159e-02f, 9.70992e-01f, 1.00769e-01f, -3.37303e-02f, 1.02356e-02f, -1.83931e-03f }, // 116/128
{ -2.08645e-03f, 1.28947e-02f, -5.39305e-02f, 9.74342e-01f, 9.19033e-02f, -3.09033e-02f, 9.39154e-03f, -1.68894e-03f }, // 117/128
{ -1.90738e-03f, 1.18034e-02f, -4.95412e-02f, 9.77526e-01f, 8.31162e-02f, -2.80746e-02f, 8.54441e-03f, -1.53777e-03f }, // 118/128
{ -1.72594e-03f, 1.06946e-02f, -4.50483e-02f, 9.80543e-01f, 7.44095e-02f, -2.52457e-02f, 7.69462e-03f, -1.38589e-03f }, // 119/128
{ -1.54221e-03f, 9.56876e-03f, -4.04519e-02f, 9.83392e-01f, 6.57852e-02f, -2.24178e-02f, 6.84261e-03f, -1.23337e-03f }, // 120/128
{ -1.35627e-03f, 8.42626e-03f, -3.57525e-02f, 9.86071e-01f, 5.72454e-02f, -1.95925e-02f, 5.98883e-03f, -1.08030e-03f }, // 121/128
{ -1.16820e-03f, 7.26755e-03f, -3.09503e-02f, 9.88580e-01f, 4.87921e-02f, -1.67710e-02f, 5.13372e-03f, -9.26747e-04f }, // 122/128
{ -9.78093e-04f, 6.09305e-03f, -2.60456e-02f, 9.90917e-01f, 4.04274e-02f, -1.39548e-02f, 4.27773e-03f, -7.72802e-04f }, // 123/128
{ -7.86031e-04f, 4.90322e-03f, -2.10389e-02f, 9.93082e-01f, 3.21531e-02f, -1.11453e-02f, 3.42130e-03f, -6.18544e-04f }, // 124/128
{ -5.92100e-04f, 3.69852e-03f, -1.59305e-02f, 9.95074e-01f, 2.39714e-02f, -8.34364e-03f, 2.56486e-03f, -4.64053e-04f }, // 125/128
{ -3.96391e-04f, 2.47942e-03f, -1.07209e-02f, 9.96891e-01f, 1.58840e-02f, -5.55134e-03f, 1.70888e-03f, -3.09412e-04f }, // 126/128
{ -1.98993e-04f, 1.24642e-03f, -5.41054e-03f, 9.98534e-01f, 7.89295e-03f, -2.76968e-03f, 8.53777e-04f, -1.54700e-04f }, // 127/128
{ 0.00000e+00f, 0.00000e+00f, 0.00000e+00f, 1.00000e+00f, 0.00000e+00f, 0.00000e+00f, 0.00000e+00f, 0.00000e+00f }, // 128/128
};
}

55
src/dsp/filter/interpolator/QPSKInterpolator.java Normal file
View File

@@ -0,0 +1,55 @@
package dsp.filter.interpolator;
import java.util.Arrays;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import sample.complex.ComplexSample;
public class QPSKInterpolator extends Interpolator
{
private final static Logger mLog = LoggerFactory.getLogger( QPSKInterpolator.class );
/**
* Calculates an interpolated value from the 8 samples beginning at the
* offset index. Uses the mu value to determine which of 128 filter kernels
* to use in order to closely approximate the ideal frequency response for
* the value of mu, ranging from 0.0 to 1.0, indicating the interpolated
* position in the sample set ranging from offset to offset + 7.
*
* @param samples - sample array of length at least offset + 7
*
* @param mu - interpolated sample position between 0 and 1.0
*
* @return - interpolated sample value
*/
public ComplexSample filter( ComplexSample[] samples, int offset, float mu )
{
/* Ensure we have enough samples in the array */
assert( samples.length >= offset + 7 );
/* Identify the filter bank that corresponds to mu */
int index = (int)( NSTEPS * mu );
float realAccumulator = ( TAPS[ index ][ 7 ] * samples[ offset ].real() );
realAccumulator += ( TAPS[ index ][ 6 ] * samples[ offset + 1 ].real() );
realAccumulator += ( TAPS[ index ][ 5 ] * samples[ offset + 2 ].real() );
realAccumulator += ( TAPS[ index ][ 4 ] * samples[ offset + 3 ].real() );
realAccumulator += ( TAPS[ index ][ 3 ] * samples[ offset + 4 ].real() );
realAccumulator += ( TAPS[ index ][ 2 ] * samples[ offset + 5 ].real() );
realAccumulator += ( TAPS[ index ][ 1 ] * samples[ offset + 6 ].real() );
realAccumulator += ( TAPS[ index ][ 0 ] * samples[ offset + 7 ].real() );
float imaginaryAccumulator = ( TAPS[ index ][ 7 ] * samples[ offset ].imaginary() );
imaginaryAccumulator += ( TAPS[ index ][ 6 ] * samples[ offset + 1 ].imaginary() );
imaginaryAccumulator += ( TAPS[ index ][ 5 ] * samples[ offset + 2 ].imaginary() );
imaginaryAccumulator += ( TAPS[ index ][ 4 ] * samples[ offset + 3 ].imaginary() );
imaginaryAccumulator += ( TAPS[ index ][ 3 ] * samples[ offset + 4 ].imaginary() );
imaginaryAccumulator += ( TAPS[ index ][ 2 ] * samples[ offset + 5 ].imaginary() );
imaginaryAccumulator += ( TAPS[ index ][ 1 ] * samples[ offset + 6 ].imaginary() );
imaginaryAccumulator += ( TAPS[ index ][ 0 ] * samples[ offset + 7 ].imaginary() );
return new ComplexSample( realAccumulator, imaginaryAccumulator );
}
}

3
src/dsp/gain/DirectGainControl.java
View File

@@ -71,6 +71,8 @@ public class DirectGainControl implements GainController, RealSampleListener
{
mGain = mMaximum;
}
mLog.debug( "Gain Increase: " + mGain );
}
@Override
@@ -82,6 +84,7 @@ public class DirectGainControl implements GainController, RealSampleListener
{
mGain = mMinimum;
}
mLog.debug( "Gain Decrease: " + mGain );
}
public void setListener( RealSampleListener listener )

2
src/dsp/nbfm/FMDiscriminator.java
View File

@@ -74,7 +74,7 @@ public class FMDiscriminator implements Listener<ComplexSample>
else
{
/**
* Use the arcus tangent of imaginary (q) divided by real (i) to
* Use the arc-tangent of imaginary (q) divided by real (i) to
* get the phase angle (+/-) which was directly manipulated by the
* original message waveform during the modulation. This value now
* serves as the instantaneous amplitude of the demodulated signal

384
src/dsp/psk/CQPSKDemodulator.java Normal file
View File

@@ -0,0 +1,384 @@
package dsp.psk;
/*******************************************************************************
* SDR Trunk
* Copyright (C) 2015 Dennis Sheirer
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>
******************************************************************************/
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import sample.Listener;
import sample.Provider;
import sample.complex.ComplexSample;
import dsp.filter.interpolator.QPSKInterpolator;
public class CQPSKDemodulator implements Listener<ComplexSample>,
Provider<ComplexSample>
{
private final static Logger mLog =
LoggerFactory.getLogger( CQPSKDemodulator.class );
/* Sample Rate 48000 / Symbol Rate 4800 = Samples Per Symbol 10 */
public static final int SAMPLES_PER_SYMBOL = 10;
public static final int d_twice_sps = 20;
public static final int half_sps = 5;
public static final double TWO_PI = 2.0 * Math.PI;
/* CQPSK constellation is offset from normal QPSK by 45 degrees or pi/4 */
public static final float THETA = (float)( Math.PI / 4.0d );
private float d_mu = 10.5f;
private float d_gain_mu = 0.05f;
/* samples per symbol */
private float d_omega = 10.0f;
private float d_half_omega = 5.0f;
private float d_gain_omega = 0.1f * d_gain_mu * d_gain_mu;
private float d_omega_rel = 0.005f;
private float d_min_omega = d_omega * ( 1.0f - d_omega_rel );
private float d_max_omega = d_omega * ( 1.0f + d_omega_rel );
private float d_omega_mid = 10.0f;
private float d_phase = 0.0f;
private float d_freq = 0.0f;
private ComplexSample[] d_dl = new ComplexSample[ 40 ];
private int d_dl_index = 0;
private Listener<ComplexSample> mListener;
private ComplexSample[] mConstellationPoints;
private SymbolTracker mSymbolTracker = new SymbolTracker();
private QPSKPhaseErrorTracker mPhaseTracker = new QPSKPhaseErrorTracker();
private QPSKInterpolator mInterpolator = new QPSKInterpolator();
private ComplexSample d_last_sample = new ComplexSample( 0.0f, 0.0f );
public CQPSKDemodulator()
{
createConstellationPoints();
/* prefill the delay line */
for( int x = 0; x < 40; x++ )
{
d_dl[ x ] = new ComplexSample( 0.0f, 0.0f );
}
}
private void createConstellationPoints()
{
mConstellationPoints = new ComplexSample[ 4 ];
for( int x = 0; x < 4; x++ )
{
mConstellationPoints[ x ] = ComplexSample.fromAngle(
( (float)( TWO_PI / 4.0f ) * (float)x ) );
}
}
@Override
public void receive( ComplexSample sample )
{
/* skip a number of symbols between sampling */
d_mu--;
/* increment phase based on the frequency of the rotation */
d_phase += d_freq;
/* keep phase clamped and not walk to infinity */
unwrapPhase();
/* NCO value for derotating the current sample */
ComplexSample nco = ComplexSample.fromAngle( d_phase + THETA );
/* Mixed/downconverted symbol */
ComplexSample symbol = ComplexSample.multiply( nco, sample );
/* Fill up the delay line for the interpolator */
d_dl[ d_dl_index ] = symbol;
d_dl[ d_dl_index + d_twice_sps ] = symbol;
/* Keep the delay line index in bounds */
d_dl_index = ( d_dl_index + 1 ) % d_twice_sps;
if( d_mu <= 1.0f )
{
ComplexSample interp_samp_mid = mInterpolator.filter( d_dl, d_dl_index, d_mu );
ComplexSample interp_samp = mInterpolator.filter( d_dl, d_dl_index + half_sps, d_mu );
float error_real = ( d_last_sample.real() - interp_samp.real() ) * interp_samp_mid.real();
float error_imag = ( d_last_sample.imaginary() - interp_samp.imaginary() ) * interp_samp_mid.imaginary();
ComplexSample diffdec = ComplexSample.multiply( interp_samp, d_last_sample.conjugate() );
d_last_sample = interp_samp;
float symbol_error = normalize( error_real + error_imag ); //Garner loop error
d_omega = d_omega + d_gain_omega * symbol_error * interp_samp.magnitude();
d_omega = d_omega_mid + clip( d_omega_mid, d_omega_rel );
d_mu += d_omega + d_gain_mu * symbol_error;
// mSymbolTracker.receive( interpolated );
mPhaseTracker.receive( diffdec );
if( mListener != null )
{
// mListener.receive( interp_samp );
mListener.receive( diffdec );
}
}
}
private float normalize( float symbol_error )
{
if( Float.isNaN( symbol_error ) )
{
return 0.0f;
}
if( symbol_error < -1.0 )
{
return -1.0f;
}
if( symbol_error > 1.0 )
{
return 1.0f;
}
return symbol_error;
}
/**
* Constrains value to the range of ( -maximum <> maximum )
*/
private float clip( float value, float maximum )
{
if( value > maximum )
{
return maximum;
}
else if( value < -maximum )
{
return -maximum;
}
return value;
}
public static int getQPSKConstellationPoint( ComplexSample sample )
{
if( sample.real() >= 0.0f )
{
if( sample.imaginary() >= 0.0f )
{
return 0;
}
else
{
return 2;
}
}
else
{
if( sample.imaginary() >= 0.0f )
{
return 1;
}
else
{
return 3;
}
}
}
private void unwrapPhase()
{
while( d_phase > TWO_PI )
{
d_phase -= TWO_PI;
}
while( d_phase < -TWO_PI )
{
d_phase += TWO_PI;
}
}
/**
* Mueller & Mueller symbol timing tracker
*/
public class SymbolTracker implements Listener<ComplexSample>
{
ComplexSample mPoint2T = new ComplexSample();
ComplexSample mPoint1T = new ComplexSample();
ComplexSample mPoint0T = new ComplexSample();
ComplexSample mConstellation2T = new ComplexSample();
ComplexSample mConstellation1T = new ComplexSample();
ComplexSample mConstellation0T = new ComplexSample();
@Override
public void receive( ComplexSample sample )
{
mPoint2T = mPoint1T;
mPoint1T = mPoint0T;
mPoint0T = sample;
mConstellation2T = mConstellation1T;
mConstellation1T = mConstellation0T;
int currentConstellation = getQPSKConstellationPoint( mPoint0T );
mConstellation0T = mConstellationPoints[ currentConstellation ];
ComplexSample x = ComplexSample.multiply(
ComplexSample.subtract( mConstellation0T, mConstellation2T ),
mPoint1T.conjugate() );
ComplexSample y = ComplexSample.multiply(
ComplexSample.subtract( mPoint0T, mPoint2T ),
mConstellation1T.conjugate() );
ComplexSample u = ComplexSample.subtract( y, x );
/* Real part of u contains error -- constrain to -1.0 to 1.0 */
float mm_error = clip( u.real(), 1.0f );
/* Update omega (samples per symbol) based on loop error */
d_omega = d_omega + d_gain_omega * mm_error;
/* Make sure we don't walk away */
d_omega = d_omega_mid + clip( d_omega - d_omega_mid, d_omega_rel );
/* update mu based on loop error */
d_mu += d_omega + d_gain_mu * mm_error;
}
}
/**
* Implements a control loop for QPSK
*
* Ported to java from gnuradio/control_loop and gnuradio/mpsk_receiver_cc
* using initialization values from OP25/cqpsk.py
*/
public class QPSKPhaseErrorTracker implements Listener<ComplexSample>
{
private float d_loop_bw = 0.03f;
private float d_damping = (float)Math.sqrt( 2.0 ) / 2.0f;
private float d_alpha = 0.03f;
private float d_beta = 0.125f * d_alpha * d_alpha;
private float d_max_freq = ( 2.0f * (float)Math.PI * 1200.0f ) / 48000.0f;
public QPSKPhaseErrorTracker()
{
}
@Override
public void receive( ComplexSample sample )
{
float phase_error = -getPhaseError( sample );
advance_loop(phase_error, sample );
unwrapPhase();
frequency_limit();
}
private void advance_loop( float phase_error, ComplexSample sample )
{
float abs = sample.magnitude();
d_freq += d_beta * phase_error * abs;
d_phase += d_freq + d_alpha * phase_error * abs;
}
private void frequency_limit()
{
if( d_freq > d_max_freq )
{
d_freq = d_max_freq;
}
if( d_freq < -d_max_freq )
{
d_freq = -d_max_freq;
}
}
/**
* Calculates the phase error for a qpsk sample. Standard qpsk samples
* should be aligned along the x/y axis and any deviation from either
* axis represents an error. Whichever component, real or imaginary,
* that has the lesser absolute value, represents the error, since that
* component should be zero valued.
*
* For example, constellation point 0 is zero degrees and is represented
* by a sample that contains a real = +1 and an imaginary = 0 component.
* If we sample too early or too late, that will cause a +/- phase
* deviation in the resultant sample and the sample will reflect that
* error value in the imaginary component. That deviation is the error.
*/
public float getPhaseError( ComplexSample sample )
{
if( sample.realAbsolute() > sample.imaginaryAbsolute() )
{
if( sample.real() > 0 )
{
return -sample.imaginary();
}
else
{
return sample.imaginary();
}
}
else
{
if( sample.imaginary() > 0 )
{
return sample.real();
}
else
{
return -sample.real();
}
}
}
}
@Override
public void setListener( Listener<ComplexSample> listener )
{
mListener = listener;
}
@Override
public void removeListener( Listener<ComplexSample> listener )
{
mListener = null;
}
}

2
src/dsp/symbol/FrameSync.java
View File

@@ -2,7 +2,7 @@ package dsp.symbol;
public enum FrameSync
{
P25_PHASE1( 0x5575F5FF77FFl ),
P25_PHASE1( 0x5575F5FF77FFl ), //+3 +3 +3 +3 +3 -3 +3 +3 -3 -3 +3 +3 -3 -3 -3 -3 +3 -3 +3 -3 -3 -3 -3 -3
P25_PHASE1_INVERTED( 0xFFDF5F55DD55l );
private long mSync;