gri_control_loop Class Reference

#include <gri_control_loop.h>

Inheritance diagram for gri_control_loop:

List of all members.

Public Member Functions
	gri_control_loop (float loop_bw, float max_freq, float min_freq)
virtual	~gri_control_loop ()
void	update_gains ()
	update the system gains from the loop bandwidth and damping factor
void	advance_loop (float error)
	update the system gains from the loop bandwidth and damping factor
void	phase_wrap ()
	Keep the phase between -2pi and 2pi.
void	frequency_limit ()
	Keep the frequency between d_min_freq and d_max_freq.
void	set_loop_bandwidth (float bw)
	Set the loop bandwidth.
void	set_damping_factor (float df)
	Set the loop damping factor.
void	set_alpha (float alpha)
	Set the loop gain alpha.
void	set_beta (float beta)
	Set the loop gain beta.
void	set_frequency (float freq)
	Set the control loop's frequency.
void	set_phase (float phase)
	Set the control loop's phase.
void	set_max_freq (float freq)
	Set the control loop's maximum frequency.
void	set_min_freq (float freq)
	Set the control loop's minimum frequency.
float	get_loop_bandwidth () const
	Returns the loop bandwidth.
float	get_damping_factor () const
	Returns the loop damping factor.
float	get_alpha () const
	Returns the loop gain alpha.
float	get_beta () const
	Returns the loop gain beta.
float	get_frequency () const
	Get the control loop's frequency estimate.
float	get_phase () const
	Get the control loop's phase estimate.
float	get_max_freq () const
	Get the control loop's maximum frequency.
float	get_min_freq () const
	Get the control loop's minimum frequency.
Protected Attributes
float	d_phase
float	d_freq
float	d_max_freq
float	d_min_freq
float	d_damping
float	d_loop_bw
float	d_alpha
float	d_beta

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Constructor & Destructor Documentation

gri_control_loop::gri_control_loop	(	float	loop_bw,
		float	max_freq,
		float	min_freq
	)

virtual gri_control_loop::~gri_control_loop

(

)

[virtual]

---

Member Function Documentation

void gri_control_loop::advance_loop

(

float

error

)

update the system gains from the loop bandwidth and damping factor

This function updates the system gains based on the loop bandwidth and damping factor of the system. These two factors can be set separately through their own set functions.

void gri_control_loop::frequency_limit

(

)

Keep the frequency between d_min_freq and d_max_freq.

This function keeps the frequency between d_min_freq and d_max_freq. If the frequency is greater than d_max_freq, it is set to d_max_freq. If the frequency is less than d_min_freq, it is set to d_min_freq.

This function should be called after advance_loop to keep the frequency in the specified region. It is set as a separate method in case another way is desired as this is fairly heavy-handed.

float gri_control_loop::get_alpha

(

)

const

Returns the loop gain alpha.

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

float gri_control_loop::get_beta

(

)

const

Returns the loop gain beta.

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

float gri_control_loop::get_damping_factor

(

)

const

Returns the loop damping factor.

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

float gri_control_loop::get_frequency

(

)

const

Get the control loop's frequency estimate.

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

float gri_control_loop::get_loop_bandwidth

(

)

const

Returns the loop bandwidth.

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

float gri_control_loop::get_max_freq

(

)

const

Get the control loop's maximum frequency.

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

float gri_control_loop::get_min_freq

(

)

const

Get the control loop's minimum frequency.

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

float gri_control_loop::get_phase

(

)

const

Get the control loop's phase estimate.

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

void gri_control_loop::phase_wrap

(

)

Keep the phase between -2pi and 2pi.

This function keeps the phase between -2pi and 2pi. If the phase is greater than 2pi by d, it wraps around to be -2pi+d; similarly if it is less than -2pi by d, it wraps around to 2pi-d.

This function should be called after advance_loop to keep the phase in a good operating region. It is set as a separate method in case another way is desired as this is fairly heavy-handed.

void gri_control_loop::set_alpha

(

float

alpha

)

Set the loop gain alpha.

Set's the loop filter's alpha gain parameter.

This value should really only be set by adjusting the loop bandwidth and damping factor.

Parameters:

alpha

(float) new alpha gain

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

void gri_control_loop::set_beta

(

float

beta

)

Set the loop gain beta.

Set's the loop filter's beta gain parameter.

This value should really only be set by adjusting the loop bandwidth and damping factor.

Parameters:

beta	(float) new beta gain

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

void gri_control_loop::set_damping_factor

(

float

df

)

Set the loop damping factor.

Set the loop filter's damping factor to df. The damping factor should be sqrt(2)/2.0 for critically damped systems. Set it to anything else only if you know what you are doing. It must be a number between 0 and 1.

When a new damping factor is set, the gains, alpha and beta, of the loop are recalculated by a call to update_gains().

Parameters:

df	(float) new damping factor

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

void gri_control_loop::set_frequency

(

float

freq

)

Set the control loop's frequency.

Set's the control loop's frequency. While this is normally updated by the inner loop of the algorithm, it could be useful to manually initialize, set, or reset this under certain circumstances.

Parameters:

freq	(float) new frequency

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

void gri_control_loop::set_loop_bandwidth

(

float

bw

)

Set the loop bandwidth.

Set the loop filter's bandwidth to bw. This should be between 2*pi/200 and 2*pi/100 (in rads/samp). It must also be a positive number.

When a new damping factor is set, the gains, alpha and beta, of the loop are recalculated by a call to update_gains().

Parameters:

bw	(float) new bandwidth

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

void gri_control_loop::set_max_freq

(

float

freq

)

Set the control loop's maximum frequency.

Set the maximum frequency the control loop can track.

Parameters:

freq	(float) new max frequency

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

void gri_control_loop::set_min_freq

(

float

freq

)

Set the control loop's minimum frequency.

Set the minimum frequency the control loop can track.

Parameters:

freq	(float) new min frequency

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

void gri_control_loop::set_phase

(

float

phase

)

Set the control loop's phase.

Set's the control loop's phase. While this is normally updated by the inner loop of the algorithm, it could be useful to manually initialize, set, or reset this under certain circumstances.

Parameters:

phase

(float) new phase

Reimplemented in gr::analog::pll_carriertracking_cc_impl, gr::analog::pll_freqdet_cf_impl, and gr::analog::pll_refout_cc_impl.

void gri_control_loop::update_gains

(

)

update the system gains from the loop bandwidth and damping factor

This function updates the system gains based on the loop bandwidth and damping factor of the system. These two factors can be set separately through their own set functions.

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Member Data Documentation

float gri_control_loop::d_alpha [protected]

float gri_control_loop::d_beta [protected]

float gri_control_loop::d_damping [protected]

float gri_control_loop::d_freq [protected]

float gri_control_loop::d_loop_bw [protected]

float gri_control_loop::d_max_freq [protected]

float gri_control_loop::d_min_freq [protected]

float gri_control_loop::d_phase [protected]

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

• gri_control_loop.h