Rectangular digital constellation. More...

#include <gnuradio/digital/constellation.h>

Public Types
typedef std::shared_ptr< constellation_rect >	sptr

Public Types inherited from gr::digital::constellation
enum	normalization_t { NO_NORMALIZATION , POWER_NORMALIZATION , AMPLITUDE_NORMALIZATION }

Public Member Functions
	~constellation_rect () override

Public Member Functions inherited from gr::digital::constellation_sector
	constellation_sector (std::vector< gr_complex > constell, std::vector< int > pre_diff_code, unsigned int rotational_symmetry, unsigned int dimensionality, unsigned int n_sectors, normalization_t normalization=AMPLITUDE_NORMALIZATION)

	~constellation_sector () override

unsigned int	decision_maker (const gr_complex *sample) override
	Returns the constellation point that matches best. More...

Public Member Functions inherited from gr::digital::constellation
	constellation (std::vector< gr_complex > constell, std::vector< int > pre_diff_code, unsigned int rotational_symmetry, unsigned int dimensionality, normalization_t normalization=AMPLITUDE_NORMALIZATION, float npwr=1.0)

	constellation ()

virtual	~constellation ()

void	normalize (normalization_t normalization)
	Normalizes the constellation. More...

void	map_to_points (unsigned int value, gr_complex *points)
	Returns the constellation points for a symbol value. More...

std::vector< gr_complex >	map_to_points_v (unsigned int value)

unsigned int	decision_maker_v (std::vector< gr_complex > sample)
	Takes a vector rather than a pointer. Better for SWIG wrapping. More...

unsigned int	decision_maker_pe (const gr_complex sample, float phase_error)
	Also calculates the phase error. More...

virtual void	calc_metric (const gr_complex sample, float metric, gr::digital::trellis_metric_type_t type)
	Calculates distance. More...

virtual void	calc_euclidean_metric (const gr_complex sample, float metric)

virtual void	calc_hard_symbol_metric (const gr_complex sample, float metric)

std::vector< gr_complex >	points ()
	Returns the set of points in this constellation. More...

std::vector< gr_complex >	s_points ()
	Returns the vector of points in this constellation. Raise error if dimensionality is not one. More...

std::vector< std::vector< gr_complex > >	v_points ()
	Returns a vector of vectors of points. More...

bool	apply_pre_diff_code ()
	Whether to apply an encoding before doing differential encoding. (e.g. gray coding) More...

void	set_pre_diff_code (bool a)
	Whether to apply an encoding before doing differential encoding. (e.g. gray coding) More...

std::vector< int >	pre_diff_code ()
	Returns the encoding to apply before differential encoding. More...

unsigned int	rotational_symmetry ()
	Returns the order of rotational symmetry. More...

unsigned int	dimensionality ()
	Returns the number of complex numbers in a single symbol. More...

unsigned int	bits_per_symbol ()

unsigned int	arity ()

constellation_sptr	base ()

pmt::pmt_t	as_pmt ()

void	gen_soft_dec_lut (int precision, float npwr=-1)
	Generates the soft decision LUT based on constellation and symbol map. More...

virtual std::vector< float >	calc_soft_dec (gr_complex sample, float npwr=-1)
	Calculate soft decisions for the given `sample`. More...

void	set_soft_dec_lut (const std::vector< std::vector< float >> &soft_dec_lut, int precision)
	Define a soft decision look-up table. More...

void	set_npwr (float npwr)
	Sets the constellation noise power and recalculates LUT given `npwr`. More...

bool	has_soft_dec_lut ()
	Returns True if the soft decision LUT has been defined, False otherwise. More...

std::vector< std::vector< float > >	soft_dec_lut ()

std::vector< float >	soft_decision_maker (gr_complex sample)
	Returns the soft decisions for the given `sample`. More...

Static Public Member Functions
static constellation_rect::sptr	make (std::vector< gr_complex > constell, std::vector< int > pre_diff_code, unsigned int rotational_symmetry, unsigned int real_sectors, unsigned int imag_sectors, float width_real_sectors, float width_imag_sectors, normalization_t normalization=AMPLITUDE_NORMALIZATION)

Protected Member Functions
	constellation_rect (std::vector< gr_complex > constell, std::vector< int > pre_diff_code, unsigned int rotational_symmetry, unsigned int real_sectors, unsigned int imag_sectors, float width_real_sectors, float width_imag_sectors, normalization_t normalization=AMPLITUDE_NORMALIZATION)

unsigned int	get_sector (const gr_complex *sample) override

gr_complex	calc_sector_center (unsigned int sector)

unsigned int	calc_sector_value (unsigned int sector) override

Protected Member Functions inherited from gr::digital::constellation_sector
void	find_sector_values ()

Protected Member Functions inherited from gr::digital::constellation
float	get_distance (unsigned int index, const gr_complex *sample)

unsigned int	get_closest_point (const gr_complex *sample)

void	calc_arity ()

void	max_min_axes ()

Additional Inherited Members
Protected Attributes inherited from gr::digital::constellation_sector
unsigned int	n_sectors

Protected Attributes inherited from gr::digital::constellation
std::vector< gr_complex >	d_constellation

std::vector< int >	d_pre_diff_code

bool	d_apply_pre_diff_code

unsigned int	d_rotational_symmetry

unsigned int	d_dimensionality

unsigned int	d_arity

float	d_scalefactor
	The factor by which the user given constellation points were scaled by to achieve an average amplitude of 1. More...

float	d_maxamp

float	d_re_min

float	d_re_max

float	d_im_min

float	d_im_max

std::vector< std::vector< float > >	d_soft_dec_lut

int	d_lut_precision

float	d_lut_scale

float	d_npwr

float	d_padding

bool	d_use_external_lut

Detailed Description

Rectangular digital constellation.

Only implemented for 1-(complex)dimensional constellation.

Constellation space is divided into rectangular sectors. Each sector is associated with the nearest constellation point.

Works well for square QAM.

Works for any generic constellation provided sectors are not too large.

Member Typedef Documentation

◆ sptr

typedef std::shared_ptr<constellation_rect> gr::digital::constellation_rect::sptr

Constructor & Destructor Documentation

◆ ~constellation_rect()

gr::digital::constellation_rect::~constellation_rect ( )

override

◆ constellation_rect()

gr::digital::constellation_rect::constellation_rect	(	std::vector< gr_complex >	constell,
		std::vector< int >	pre_diff_code,
		unsigned int	rotational_symmetry,
		unsigned int	real_sectors,
		unsigned int	imag_sectors,
		float	width_real_sectors,
		float	width_imag_sectors,
		normalization_t	normalization = `AMPLITUDE_NORMALIZATION`
	)

protected

Member Function Documentation

◆ calc_sector_center()

gr_complex gr::digital::constellation_rect::calc_sector_center ( unsigned int sector )

protected

◆ calc_sector_value()

unsigned int gr::digital::constellation_rect::calc_sector_value ( unsigned int sector )

overrideprotectedvirtual

Implements gr::digital::constellation_sector.

Reimplemented in gr::digital::constellation_expl_rect.

◆ get_sector()

unsigned int gr::digital::constellation_rect::get_sector ( const gr_complex * sample )

overrideprotectedvirtual

Implements gr::digital::constellation_sector.

◆ make()

static constellation_rect::sptr gr::digital::constellation_rect::make	(	std::vector< gr_complex >	constell,
		std::vector< int >	pre_diff_code,
		unsigned int	rotational_symmetry,
		unsigned int	real_sectors,
		unsigned int	imag_sectors,
		float	width_real_sectors,
		float	width_imag_sectors,
		normalization_t	normalization = `AMPLITUDE_NORMALIZATION`
	)

static

Make a rectangular constellation object.

Parameters

constell	List of constellation points (order of list matches pre_diff_code)
pre_diff_code	List of alphabet symbols (before applying any differential coding) (order of list matches constell)
rotational_symmetry	Number of rotations around unit circle that have the same representation.
real_sectors	Number of sectors the real axis is split in to.
imag_sectors	Number of sectors the imag axis is split in to.
width_real_sectors	width of each real sector to calculate decision boundaries.
width_imag_sectors	width of each imag sector to calculate decision boundaries.
normalization	Use AMPLITUDE_NORMALIZATION to normalize points to mean(abs(points))=1 (default), POWER_NORMALIZATION to normalize points to mean(abs(points)^2)=1 or NO_NORMALIZATION to keep the original amplitude.

The documentation for this class was generated from the following file:

constellation.h

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Additional Inherited Members