sdrangel/modemm17/CarrierDetect.h

41 wiersze
838 B
C++

// Copyright 2020 Mobilinkd LLC.
#pragma once
#include "IirFilter.h"
#include <array>
#include <algorithm>
#include <numeric>
#include <cmath>
#include <tuple>
namespace modemm17
{
struct CarrierDetect
{
using result_t = std::tuple<bool, float>;
BaseIirFilter<3> filter_;
float lock_;
float unlock_;
bool locked_ = false;
CarrierDetect(std::array<float, 3> const& b, std::array<float, 3> const& a, float lock_level, float unlock_level)
: filter_(b, a), lock_(lock_level), unlock_(unlock_level)
{
}
result_t operator()(float value)
{
auto filtered = filter_(std::abs(value));
if (locked_ && (filtered > unlock_)) locked_ = false;
else if (!locked_ && (filtered < lock_)) locked_ = true;
return std::make_tuple(locked_, filtered);
}
};
} // modemm17