mirror of
https://github.com/f4exb/sdrangel.git
synced 2024-12-23 18:15:45 -05:00
192 lines
5.1 KiB
C++
192 lines
5.1 KiB
C++
///////////////////////////////////////////////////////////////////////////////////////
|
|
// Copyright (C) 2015-2019 Edouard Griffiths, F4EXB <f4exb06@gmail.com> //
|
|
// //
|
|
// 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 as 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 V3 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/>. //
|
|
///////////////////////////////////////////////////////////////////////////////////////
|
|
|
|
#include <algorithm>
|
|
#include "dsp/agc.h"
|
|
|
|
#include "util/stepfunctions.h"
|
|
|
|
AGC::AGC(int historySize, double R) :
|
|
m_u0(1.0),
|
|
m_R(R),
|
|
m_moving_average(historySize, m_R),
|
|
m_historySize(historySize),
|
|
m_count(0)
|
|
{}
|
|
|
|
AGC::~AGC()
|
|
{}
|
|
|
|
void AGC::resize(int historySize, double R)
|
|
{
|
|
m_R = R;
|
|
m_moving_average.resize(historySize, R);
|
|
m_historySize = historySize;
|
|
m_count = 0;
|
|
}
|
|
|
|
Real AGC::getValue()
|
|
{
|
|
return m_u0;
|
|
}
|
|
|
|
Real AGC::getAverage()
|
|
{
|
|
return m_moving_average.average();
|
|
}
|
|
|
|
|
|
MagAGC::MagAGC(int historySize, double R, double threshold) :
|
|
AGC(historySize, R),
|
|
m_squared(false),
|
|
m_magsq(0.0),
|
|
m_threshold(threshold),
|
|
m_thresholdEnable(true),
|
|
m_gate(0),
|
|
m_stepLength(std::min(2400, historySize/2)), // max 50 ms (at 48 kHz)
|
|
m_stepDelta(1.0/m_stepLength),
|
|
m_stepUpCounter(0),
|
|
m_stepDownCounter(0),
|
|
m_gateCounter(0),
|
|
m_stepDownDelay(historySize),
|
|
m_hardLimiting(false)
|
|
{}
|
|
|
|
MagAGC::~MagAGC()
|
|
{}
|
|
|
|
void MagAGC::resize(int historySize, int stepLength, Real R)
|
|
{
|
|
m_stepLength = stepLength;
|
|
m_stepDelta = 1.0 / m_stepLength;
|
|
m_stepUpCounter = 0;
|
|
m_stepDownCounter = 0;
|
|
AGC::resize(historySize, R);
|
|
m_moving_average.fill(m_squared ? R : R*R);
|
|
}
|
|
|
|
void MagAGC::setOrder(double R)
|
|
{
|
|
AGC::setOrder(R);
|
|
m_moving_average.fill(m_squared ? R : R*R);
|
|
}
|
|
|
|
void MagAGC::setThresholdEnable(bool enable)
|
|
{
|
|
if (m_thresholdEnable != enable)
|
|
{
|
|
m_stepUpCounter = 0;
|
|
m_stepDownCounter = 0;
|
|
}
|
|
|
|
m_thresholdEnable = enable;
|
|
}
|
|
|
|
void MagAGC::feed(Complex& ci)
|
|
{
|
|
ci *= feedAndGetValue(ci);
|
|
}
|
|
|
|
double MagAGC::hardLimiter(double multiplier, double magsq)
|
|
{
|
|
if ((m_hardLimiting) && (multiplier*multiplier*magsq > 1.0)) {
|
|
return 1.0 / (multiplier*sqrt(magsq));
|
|
} else {
|
|
return multiplier;
|
|
}
|
|
}
|
|
|
|
double MagAGC::feedAndGetValue(const Complex& ci)
|
|
{
|
|
m_magsq = ci.real()*ci.real() + ci.imag()*ci.imag();
|
|
m_moving_average.feed(m_magsq);
|
|
m_u0 = m_R / (m_squared ? m_moving_average.average() : sqrt(m_moving_average.average()));
|
|
|
|
if (m_thresholdEnable)
|
|
{
|
|
bool open = false;
|
|
|
|
if (m_magsq > m_threshold)
|
|
{
|
|
if (m_gateCounter < m_gate) {
|
|
m_gateCounter++;
|
|
} else {
|
|
open = true;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
m_gateCounter = 0;
|
|
}
|
|
|
|
if (open)
|
|
{
|
|
m_count = m_stepDownDelay; // delay before step down (grace delay)
|
|
}
|
|
else
|
|
{
|
|
m_count--;
|
|
m_gateCounter = m_gate; // keep gate open during grace
|
|
}
|
|
|
|
if (m_count > 0) // up phase
|
|
{
|
|
m_stepDownCounter = m_stepUpCounter; // prepare for step down
|
|
|
|
if (m_stepUpCounter < m_stepLength) // step up
|
|
{
|
|
m_stepUpCounter++;
|
|
return hardLimiter(m_u0 * StepFunctions::smootherstep(m_stepUpCounter * m_stepDelta), m_magsq);
|
|
}
|
|
else // steady open
|
|
{
|
|
return hardLimiter(m_u0, m_magsq);
|
|
}
|
|
}
|
|
else // down phase
|
|
{
|
|
m_stepUpCounter = m_stepDownCounter; // prepare for step up
|
|
|
|
if (m_stepDownCounter > 0) // step down
|
|
{
|
|
m_stepDownCounter--;
|
|
return hardLimiter(m_u0 * StepFunctions::smootherstep(m_stepDownCounter * m_stepDelta), m_magsq);
|
|
}
|
|
else // steady closed
|
|
{
|
|
return 0.0;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
return hardLimiter(m_u0, m_magsq);
|
|
}
|
|
}
|
|
|
|
float MagAGC::getStepValue() const
|
|
{
|
|
if (m_count > 0) // up phase
|
|
{
|
|
return StepFunctions::smootherstep(m_stepUpCounter * m_stepDelta); // step up
|
|
}
|
|
else // down phase
|
|
{
|
|
return StepFunctions::smootherstep(m_stepDownCounter * m_stepDelta); // step down
|
|
}
|
|
}
|