decibel.hpp File Reference

#include <cassert>
#include <cmath>
#include <electro/electro.hpp>

Go to the source code of this file.

Classes
struct	electro::decibel_unit
	A dimensionless logarithmic ratio, measured in decibels. More...
struct	electro::milliwatt_reference
	Reference of 1 mW, for dBm. More...
struct	electro::watt_reference
	Reference of 1 W, for dBW. More...
struct	electro::volt_reference
	Reference of 1 V, for dBV. More...
struct	electro::millivolt_reference
	Reference of 1 mV, for dBmV. More...
struct	electro::microvolt_reference
	Reference of 1 µV, for dBµV. More...
struct	electro::is_level< T >
	Trait to detect level specializations. More...
struct	electro::is_level< level< Reference, Rep, Precision > >
class	electro::level< Reference, Rep, Precision >
	An absolute point on a logarithmic scale, relative to a reference. More...
struct	electro::quantity_suffix< decibel_unit, Precision >
	Decibels opt out of the generic SI-prefix suffix machinery. More...

Namespaces
namespace	electro
	Electrical unit types and utilities.
namespace	std
namespace	electro_literals
	User-defined literals for electrical quantity types.

Concepts
concept	electro::decibel_reference
	Concept for decibel reference tags.

Typedefs
template<typename Rep , typename Precision = std::ratio<1>>
using	electro::gain = quantity< decibel_unit, Rep, Precision >
	A logarithmic ratio with configurable representation and precision.
using	electro::decibels = gain< int64_t >
	Gain with 1 dB precision.
using	electro::centidecibels = gain< int64_t, std::centi >
	Gain with 0.01 dB precision.
using	electro::millidecibels = gain< int64_t, std::milli >
	Gain with 0.001 dB precision.
template<typename Rep , typename Precision = std::ratio<1>>
using	electro::dbm_level = level< milliwatt_reference, Rep, Precision >
	A level referenced to 1 mW.
template<typename Rep , typename Precision = std::ratio<1>>
using	electro::dbw_level = level< watt_reference, Rep, Precision >
	A level referenced to 1 W.
template<typename Rep , typename Precision = std::ratio<1>>
using	electro::dbv_level = level< volt_reference, Rep, Precision >
	A level referenced to 1 V.
template<typename Rep , typename Precision = std::ratio<1>>
using	electro::dbmv_level = level< millivolt_reference, Rep, Precision >
	A level referenced to 1 mV.
template<typename Rep , typename Precision = std::ratio<1>>
using	electro::dbuv_level = level< microvolt_reference, Rep, Precision >
	A level referenced to 1 µV.
using	electro::dbm = dbm_level< int64_t >
	Power level in dBm, with 1 dB precision.
using	electro::centi_dbm = dbm_level< int64_t, std::centi >
	Power level in dBm, with 0.01 dB precision.
using	electro::dbw = dbw_level< int64_t >
	Power level in dBW, with 1 dB precision.
using	electro::dbv = dbv_level< int64_t >
	Voltage level in dBV, with 1 dB precision.
using	electro::dbmv = dbmv_level< int64_t >
	Voltage level in dBmV, with 1 dB precision.
using	electro::dbuv = dbuv_level< int64_t >
	Voltage level in dBµV, with 1 dB precision.
using	electro::centi_dbuv = dbuv_level< int64_t, std::centi >
	Voltage level in dBµV, with 0.01 dB precision.

Functions
template<typename ToLevel , typename Reference , typename Rep , typename Precision >
constexpr ToLevel	electro::level_cast (const level< Reference, Rep, Precision > &l)
	Converts a level to a different precision or representation.
template<typename ToLevel , typename Reference , typename Rep , typename Precision >
constexpr ToLevel	electro::floor (const level< Reference, Rep, Precision > &l)
	Converts a level to the target type, rounding toward negative infinity.
template<typename ToLevel , typename Reference , typename Rep , typename Precision >
constexpr ToLevel	electro::ceil (const level< Reference, Rep, Precision > &l)
	Converts a level to the target type, rounding toward positive infinity.
template<typename ToLevel , typename Reference , typename Rep , typename Precision >
constexpr ToLevel	electro::round (const level< Reference, Rep, Precision > &l)
	Converts a level to the target type, rounding to nearest (ties to even).
template<typename Reference , typename Rep1 , typename Precision1 , typename Rep2 , typename Precision2 >
constexpr auto	electro::operator+ (const level< Reference, Rep1, Precision1 > &l, const quantity< decibel_unit, Rep2, Precision2 > &g)
	Applies a gain to a level.
template<typename Reference , typename Rep1 , typename Precision1 , typename Rep2 , typename Precision2 >
constexpr auto	electro::operator+ (const quantity< decibel_unit, Rep2, Precision2 > &g, const level< Reference, Rep1, Precision1 > &l)
	Applies a gain to a level.
template<typename Reference , typename Rep1 , typename Precision1 , typename Rep2 , typename Precision2 >
constexpr auto	electro::operator- (const level< Reference, Rep1, Precision1 > &l, const quantity< decibel_unit, Rep2, Precision2 > &g)
	Applies a loss to a level.
template<typename Reference , typename Rep1 , typename Precision1 , typename Rep2 , typename Precision2 >
constexpr auto	electro::operator- (const level< Reference, Rep1, Precision1 > &a, const level< Reference, Rep2, Precision2 > &b)
	The difference between two levels is a gain.
template<typename Reference , typename Rep1 , typename Precision1 , typename Rep2 , typename Precision2 >
constexpr bool	electro::operator== (const level< Reference, Rep1, Precision1 > &a, const level< Reference, Rep2, Precision2 > &b)
template<typename Reference , typename Rep1 , typename Precision1 , typename Rep2 , typename Precision2 > requires std::three_way_comparable<std::common_type_t<Rep1, Rep2>>
constexpr auto	electro::operator<=> (const level< Reference, Rep1, Precision1 > &a, const level< Reference, Rep2, Precision2 > &b)
template<typename Reference , typename Rep , typename Precision >
auto	electro::to_linear (const level< Reference, Rep, Precision > &l)
	Converts a level to the equivalent linear quantity.
template<typename ToLevel , typename Unit , typename Rep , typename Precision >
ToLevel	electro::to_level (const quantity< Unit, Rep, Precision > &q)
	Converts a linear quantity to a level.
template<typename Rep , typename Precision >
double	electro::power_ratio (const quantity< decibel_unit, Rep, Precision > &g)
	The linear power ratio a gain represents (10^(dB/10)).
template<typename Rep , typename Precision >
double	electro::amplitude_ratio (const quantity< decibel_unit, Rep, Precision > &g)
	The linear amplitude ratio a gain represents (10^(dB/20)).
gain< double >	electro::power_gain (double ratio)
	The gain corresponding to a linear power ratio (10*log10(ratio)).
gain< double >	electro::amplitude_gain (double ratio)
	The gain corresponding to a linear amplitude ratio (20*log10(ratio)).
template<typename Reference , typename Rep1 , typename Precision1 , typename Rep2 , typename Precision2 > requires is_power_reference_v<Reference>
auto	electro::add_powers (const level< Reference, Rep1, Precision1 > &a, const level< Reference, Rep2, Precision2 > &b)
	Combines the powers of two uncorrelated signals.
template<typename Rep , typename Precision > requires _is_decimal_precision<typename Precision::type>
std::string	electro::to_string (const quantity< decibel_unit, Rep, Precision > &g)
	Converts a gain to a string, e.g.
template<typename Reference , typename Rep , typename Precision > requires _is_decimal_precision<typename Precision::type>
std::string	electro::to_string (const level< Reference, Rep, Precision > &l)
	Converts a level to a string, e.g.
template<char... Digits>
constexpr electro::decibels	electro_literals::operator""_dB ()
	Literal for decibels (e.g., 20_dB).
template<char... Digits>
constexpr electro::centidecibels	electro_literals::operator""_cdB ()
	Literal for centidecibels, i.e.
template<char... Digits>
constexpr electro::dbm	electro_literals::operator""_dBm ()
	Literal for dBm (e.g., 20_dBm, or -73_dBm).
template<char... Digits>
constexpr electro::centi_dbm	electro_literals::operator""_cdBm ()
	Literal for dBm in 0.01 dB steps (e.g., 1301_cdBm is 13.01 dBm).
template<char... Digits>
constexpr electro::dbw	electro_literals::operator""_dBW ()
	Literal for dBW (e.g., 10_dBW).
template<char... Digits>
constexpr electro::dbv	electro_literals::operator""_dBV ()
	Literal for dBV (e.g., 6_dBV).
template<char... Digits>
constexpr electro::dbmv	electro_literals::operator""_dBmV ()
	Literal for dBmV (e.g., 40_dBmV).
template<char... Digits>
constexpr electro::dbuv	electro_literals::operator""_dBuV ()
	Literal for dBµV (e.g., 120_dBuV).
template<char... Digits>
constexpr electro::dbuv	electro_literals::operator""_dBµV ()
	Literal for dBµV (e.g., 120_dBµV).

Variables
template<typename Reference >
constexpr bool	electro::is_power_reference_v = false
	True if the reference measures a power quantity (10*log10).
template<decibel_reference Reference>
constexpr bool	electro::is_power_reference_v< Reference > = Reference::factor == 10
template<typename Reference >
constexpr bool	electro::is_field_reference_v = false
	True if the reference measures a field quantity (20*log10).
template<decibel_reference Reference>
constexpr bool	electro::is_field_reference_v< Reference > = Reference::factor == 20
template<typename T >
constexpr bool	electro::is_level_v = is_level<T>::value