Manages multiple signal path transformations in a reception model. More...

#include <SignalPath.h>

Inheritance diagram for Calibration::SignalPath:

Public Member Functions
	SignalPath (Pulsar::Calibrator::Type *)
	Default constructor.
void	set_name (const std::string &_name)
	Set the name of this instance.
void	copy (SignalPath *other)
	Copy state of other instance.
void	share (SignalPath *other)
	Share reception model and common transformations of other instance.
void	set_response (MEAL::Complex2 *)
	Set the response transformation.
void	reset ()
	Reset the response to its initial/unmodified value.
void	set_response_variation (unsigned iparam, MEAL::Univariate< MEAL::Scalar > *)
	Allow the specified response parameter to vary as a function of time.
const MEAL::Univariate< MEAL::Scalar > *	get_response_variation (unsigned iparam) const
	Get the specified response parameter temporal variation function.
void	set_impurity (MEAL::Real4 *)
	Include an impurity transformation.
void	set_basis (MEAL::Complex2 *)
	Set the transformation to the receptor basis.
bool	has_basis () const
MEAL::Complex2 *	get_basis ()
const MEAL::Complex2 *	get_basis () const
void	set_constant_pulsar_gain (bool=true)
	Set true when the pulsar Stokes parameters have been normalized.
void	set_foreach_calibrator (const MEAL::Complex2 *)
	Set the transformation to be cloned for each calibrator.
void	set_stepeach_calibrator (const VariableBackend *)
	Set the VariableBackend step to be cloned for each calibrator.
void	set_gain_variation (MEAL::Univariate< MEAL::Scalar > *)
	Set gain to the univariate function of time.
void	set_diff_gain_variation (MEAL::Univariate< MEAL::Scalar > *)
	Set differential gain to the univariate function of time.
void	set_diff_phase_variation (MEAL::Univariate< MEAL::Scalar > *)
	Set differential phase to the univariate function of time.
const MEAL::Scalar *	get_gain_variation () const
	Get the gain function of time.
const MEAL::Scalar *	get_diff_gain_variation () const
	Get the differential gain function of time.
const MEAL::Scalar *	get_diff_phase_variation () const
	Get the differential phase function of time.
void	add_calibrator_epoch (const MJD &)
	Add a step if any of the above functions require it.
void	add_gain_step (const MJD &)
	Add a step to the gain variations.
void	add_diff_gain_step (const MJD &)
	Add a step to the differential gain variations.
void	add_diff_phase_step (const MJD &)
	Add a step to the differential phase variations.
void	add_step (const MJD &mjd, Calibration::VariableBackend *backend=0)
	Insert a step into the instrumental response at the specified time.
void	add_observation_epoch (const MJD &)
	Record the epochs of observations.
void	set_reference_epoch (const MJD &epoch)
	Set the reference epoch.
void	update ()
	Update the relevant estimate.
void	fit_gain (bool flag)
	Allow the absolute gain to vary as a free parameter.
void	equal_ellipticities ()
	Set the receptor ellipticities to a single value.
bool	reduce_nfree ()
	Attempt to reduce the number of degrees of freedom in the model.
void	check_constraints ()
	Check all relevant constraints.
void	solve ()
	Solve the measurement equation.
void	add_psr_path (VariableBackendEstimate *)
	Add a new signal path for pulsar observations.
void	add_cal_path (VariableBackendEstimate *)
	Add a new signal path for poln calibrator observations.
void	fix_orientation ()
	Fix the rotation about the line of sight.
unsigned	get_cal_path_index (const MJD &) const
	Get the index for the signal path experienced by the reference source.
unsigned	get_psr_path_index (const MJD &) const
	Get the index for the signal path experienced by the pulsar.
VariableBackendEstimate *	get_backend (const MJD &epoch) const
	Get the backend that spans the specified epoch.
VariableBackendEstimate *	max_weight_backend ()
	Get the backend with the maximum weight.
void	integrate_calibrator (const MJD &epoch, const MEAL::Complex2 *xform)
	Integrate a calibrator solution.
Calibration::ReceptionModel *	get_equation ()
	Get the measurement equation.
const Calibration::ReceptionModel *	get_equation () const
	Get the measurement equation solver.
void	set_equation (Calibration::ReceptionModel *)
	Set the measurement equation.
void	set_solver (Calibration::ReceptionModel::Solver *)
	Set the algorithm used to solve the measurement equation.
void	copy_transformation (const MEAL::Complex2 *)
	Copy the parameters for the signal path experienced by the pulsar.
const MEAL::Complex2 *	get_transformation () const
	Get the instrumental transformation.
MEAL::Complex2 *	get_transformation ()
	Get the instrumental transformation.
void	add_transformation (MEAL::Complex2 *)
	Add a transformation to the ReceptionModel.
const MEAL::Complex2 *	get_pulsar_transformation (const MJD &) const
	Get the full signal path experienced by the pulsar.
void	get_covariance (std::vector< double > &covar, const MJD &epoch)
	Get the covariance vector at the specified epoch.
void	disengage_time_variations (const MJD &epoch)
	Deactivate time variations and set the Instrument to the given epoch.
void	engage_time_variations ()
	Activate time varations.
bool	get_time_variations_engaged () const
	Return true if time-variations are engaged.
void	set_step_after_cal (bool flag=true)
	Set whether steps occur before or after cals.
void	set_refcal_through_frontend (bool flag=true)
	e.g. true if noise diode illuminates feed; false if coupled after OMT
void	set_valid (bool f, const char *reason=0)
bool	get_valid () const
std::string	get_invalid_reason () const
void	set_projection (MEAL::Variable< MEAL::Complex2 > *)
MEAL::Variable< MEAL::Complex2 > *	get_projection ()
void	set_faraday_rotation (MEAL::Variable< MEAL::Complex2 > *)
MEAL::Variable< MEAL::Complex2 > *	get_faraday_rotation ()
Public Member Functions inherited from Reference::Able
	Able (const Able &)
Able &	operator= (const Able &)
unsigned	get_reference_count () const
Public Member Functions inherited from Reference::HeapTracked
	HeapTracked (const HeapTracked &)
HeapTracked &	operator= (const HeapTracked &)
bool	__is_on_heap () const

Public Attributes
MEAL::Axis< MJD >	time
	The time axis.

Static Public Attributes
static bool	verbose = false
	Verbosity flag.

Protected Types
typedef Reference::To< MEAL::Univariate< MEAL::Scalar > >	ScalarReference
	Temporal variation of response parameters.

Protected Member Functions
VariableBackendEstimate *	new_backend (MEAL::Complex2 *response=0)
	Return a newly constructed and initialized backend.
void	integrate_parameter (MEAL::Scalar *function, double value)
void	update_parameter (MEAL::Scalar *function, double value)
void	set_min_step (MEAL::Scalar *function, double minimum)
	Set the minimum step if Scalar is a Steps.
void	offset_steps (MEAL::Scalar *function, double offset)
	Offset the steps if Scalar is a Steps.
void	set_free (unsigned iparam, const MJD &mjd)
	Allow specified parameter to vary freely in step that spans mjd.
void	fix_last_step (MEAL::Scalar *function)
	Remove the last step if there is no data there.
Protected Member Functions inherited from Reference::Able
Handle *	__reference (bool active) const
void	__dereference (bool auto_delete=true) const

Protected Attributes
bool	valid
	validity flag
std::string	invalid_reason
	reason for valid == false
Reference::To< Calibration::ReceptionModel >	equation
	The measurement equation.
Reference::To< Calibration::ReceptionModel::Solver >	solver
	The algorithm used to solve the measurement equation.
Reference::To< MEAL::Complex2 >	response
	The common instrumental response to be modelled.
Reference::To< MEAL::Complex2 >	initial_response
	Clone of newly created/unmodified respone used to implement reset.
Reference::To< MEAL::Complex2 >	basis
	The basis correction computed by the BasisCorrection class.
Reference::To< MEAL::ProductRule< MEAL::Complex2 > >	instrument
	The instrumental response multiplied by the basis.
Reference::To< MEAL::Variable< MEAL::Complex2 > >	projection
	The transformation from the celestial sphere to the receptors.
Reference::To< MEAL::Variable< MEAL::Complex2 > >	faraday_rotation
	Ionospheric and interstellar Faraday rotation.
Reference::To< MEAL::ChainRule< MEAL::Complex2 > >	response_chain
	ChainRule used to model response parameter variations.
std::map< unsigned, ScalarReference >	response_variation
Calibration::ConvertMJD	convert
	Used to convert MJD to double.
std::vector< Reference::To< VariableBackendEstimate > >	backends
	The set of instrumental backend transformations for each epoch.
Reference::To< const MEAL::Complex2 >	foreach_pcal
	Transformation cloned for each calibrator observation.
Reference::To< const MEAL::Complex2 >	foreach_fcal
Reference::To< const Calibration::VariableBackend >	stepeach_pcal
Reference::To< MEAL::Univariate< MEAL::Scalar > >	gain_variation
Reference::To< MEAL::Univariate< MEAL::Scalar > >	diff_gain_variation
Reference::To< MEAL::Univariate< MEAL::Scalar > >	diff_phase_variation
Reference::To< MEAL::Real4 >	impurity
	The (optional) common instrumental impurity to be modelled.
Reference::To< MEAL::Complex2 >	solution_response
	The instrumental response returned by get_transformation.
bool	time_variations_engaged
bool	step_after_cal
bool	constant_pulsar_gain
bool	refcal_through_frontend
MJD	min_epoch
MJD	max_epoch

Additional Inherited Members
Static Public Member Functions inherited from Reference::Able
static size_t	get_instance_count ()
Static Public Member Functions inherited from Reference::HeapTracked
static void *	operator new (size_t size, void *ptr=0)
static void	operator delete (void location, void ptr)
static void	operator delete (void *location)
static size_t	get_heap_queue_size ()

Detailed Description

Manages multiple signal path transformations in a reception model.

As in Table 1 of van Straten (2004), different types of observations are subjected to different polarimetric transformations.

Each SignalPath instance manages the polarimetric tranformations for observations of a single pulsar, its reference source (e.g. noise diode), and a flux calibrator.

Multiple pulsars are managed by multiple SignalPaths that share a reception model and a common set of polarimetric transformations.

Member Function Documentation

◆ add_psr_path()

void SignalPath::add_psr_path ( VariableBackendEstimate * backend )

Add a new signal path for pulsar observations.

Signal path experienced by pulsar signal

References add_transformation(), equation, faraday_rotation, Calibration::VariableBackendEstimate::get_psr_response(), projection, and verbose.

◆ get_equation()

Calibration::ReceptionModel * SignalPath::get_equation ( )

Get the measurement equation.

Get the measurement equation solver.

References equation.

Referenced by get_covariance(), and solve().

◆ get_pulsar_transformation()

const MEAL::Complex2 * SignalPath::get_pulsar_transformation ( const MJD & epoch ) const

Get the full signal path experienced by the pulsar.

Get the signal path experienced by the pulsar.

References get_backend().

◆ max_weight_backend()

VariableBackendEstimate * SignalPath::max_weight_backend ( )

Get the backend with the maximum weight.

return the backend with the maximum weight

References backends.

Referenced by get_covariance().

◆ share()

void SignalPath::share ( SignalPath * other )

Share reception model and common transformations of other instance.

Common transformations are experienced by all sources.

References equation, faraday_rotation, impurity, projection, response, and SignalPath().

Member Data Documentation

◆ backends

std::vector< Reference::To< VariableBackendEstimate > > Calibration::SignalPath::backends

protected

The set of instrumental backend transformations for each epoch.

The VariableBackendEstimate class handles jumps in the instrumental response that apply to both calibrator and pulsar observations.

Referenced by add_observation_epoch(), add_step(), disengage_time_variations(), engage_time_variations(), get_backend(), get_covariance(), max_weight_backend(), reduce_nfree(), set_constant_pulsar_gain(), set_diff_gain_variation(), set_diff_phase_variation(), set_gain_variation(), set_refcal_through_frontend(), set_reference_epoch(), solve(), and update().

◆ impurity

Reference::To< MEAL::Real4 > Calibration::SignalPath::impurity

protected

The (optional) common instrumental impurity to be modelled.

When used, all signal paths include this transformation, which supplements the response to be modeled and output as a solution.

Referenced by add_transformation(), set_impurity(), share(), and solve().

◆ response

Reference::To< MEAL::Complex2 > Calibration::SignalPath::response

protected

The common instrumental response to be modelled.

All signal paths include this transformation, which is the response to be modeled and output as a solution.

Other transformations mostly deal with variations as a function of time, variations between signals of different types, etc.

Referenced by add_step(), copy_transformation(), disengage_time_variations(), equal_ellipticities(), fit_gain(), fix_orientation(), get_covariance(), get_transformation(), reset(), set_basis(), set_response(), share(), and update().

◆ solution_response

Reference::To< MEAL::Complex2 > Calibration::SignalPath::solution_response

protected

The instrumental response returned by get_transformation.

Place holder for fiducial solution when there are multiple signal paths.

Referenced by get_covariance(), and get_transformation().

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

SignalPath.h
SignalPath.C

Public Member Functions

Public Attributes

Static Public Attributes

Protected Types

Protected Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ add_psr_path()

◆ get_equation()

◆ get_pulsar_transformation()

◆ max_weight_backend()

◆ share()

Member Data Documentation

◆ backends

◆ impurity

◆ response

◆ solution_response