GNU Radio Manual and C++ API Reference  3.7.13.4
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gr::digital::constellation_calcdist Class Reference

Calculate Euclidian distance for any constellation. More...

#include <gnuradio/digital/constellation.h>

Public Types

typedef boost::shared_ptr< constellation_calcdistsptr
 

Public Member Functions

unsigned int decision_maker (const gr_complex *sample)
 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)
 
 constellation ()
 
virtual ~constellation ()
 
void map_to_points (unsigned int value, gr_complex *points)
 Returns the constellation points for a symbol value. More...
 
std::vector< gr_complexmap_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_complexpoints ()
 Returns the set of points in this constellation. More...
 
std::vector< gr_complexs_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=1.0)
 Generates the soft decision LUT based on constellation and symbol map. More...
 
virtual std::vector< float > calc_soft_dec (gr_complex sample, float npwr=1.0)
 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...
 
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 sptr make (std::vector< gr_complex > constell, std::vector< int > pre_diff_code, unsigned int rotational_symmetry, unsigned int dimensionality)
 

Protected Member Functions

 constellation_calcdist (std::vector< gr_complex > constell, std::vector< int > pre_diff_code, unsigned int rotational_symmetry, unsigned int dimensionality)
 
- 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
std::vector< gr_complexd_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_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
 

Detailed Description

Calculate Euclidian distance for any constellation.

Constellation which calculates the distance to each point in the constellation for decision making. Inefficient for large constellations.

Member Typedef Documentation

Constructor & Destructor Documentation

gr::digital::constellation_calcdist::constellation_calcdist ( std::vector< gr_complex constell,
std::vector< int >  pre_diff_code,
unsigned int  rotational_symmetry,
unsigned int  dimensionality 
)
protected

Member Function Documentation

unsigned int gr::digital::constellation_calcdist::decision_maker ( const gr_complex sample)
virtual

Returns the constellation point that matches best.

Implements gr::digital::constellation.

static sptr gr::digital::constellation_calcdist::make ( std::vector< gr_complex constell,
std::vector< int >  pre_diff_code,
unsigned int  rotational_symmetry,
unsigned int  dimensionality 
)
static

Make a general constellation object that calculates the Euclidean distance for hard decisions.

Parameters
constellList of constellation points (order of list matches pre_diff_code)
pre_diff_codeList of alphabet symbols (before applying any differential coding) (order of list matches constell)
rotational_symmetryNumber of rotations around unit circle that have the same representation.
dimensionalityNumber of dimensions to the constellation.

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