gr_pll_freqdet_cf Class Reference

Implements a PLL which locks to the input frequency and outputs an estimate of that frequency. Useful for FM Demod.input: stream of complex; output: stream of floats. More...

#include <gr_pll_freqdet_cf.h>

Inheritance diagram for gr_pll_freqdet_cf:

Friends
GR_CORE_API gr_pll_freqdet_cf_sptr	gr_make_pll_freqdet_cf (float loop_bw, float max_freq, float min_freq)

Additional Inherited Members
Public Types inherited from gr_block
enum	{ WORK_CALLED_PRODUCE = -2, WORK_DONE = -1 }
	Magic return values from general_work. More...
enum	tag_propagation_policy_t { TPP_DONT = 0, TPP_ALL_TO_ALL = 1, TPP_ONE_TO_ONE = 2 }
Public Member Functions inherited from gr_sync_block
virtual int	work (int noutput_items, gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)=0
	just like gr_block::general_work, only this arranges to call consume_each for you
void	forecast (int noutput_items, gr_vector_int &ninput_items_required)
	Estimate input requirements given output request.
int	general_work (int noutput_items, gr_vector_int &ninput_items, gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
	compute output items from input items
int	fixed_rate_ninput_to_noutput (int ninput)
	Given ninput samples, return number of output samples that will be produced. N.B. this is only defined if fixed_rate returns true. Generally speaking, you don't need to override this.
int	fixed_rate_noutput_to_ninput (int noutput)
	Given noutput samples, return number of input samples required to produce noutput. N.B. this is only defined if fixed_rate returns true. Generally speaking, you don't need to override this.
Public Member Functions inherited from gri_control_loop
	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 Costas loop's frequency.
void	set_phase (float phase)
	Set the Costas loop's phase.
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 Costas loop's frequency estimate.
float	get_phase () const
	Get the Costas loop's phase estimate.
Protected Types inherited from gr_basic_block
enum	vcolor { WHITE, GREY, BLACK }
Protected Member Functions inherited from gr_sync_block
	gr_sync_block (void)
	gr_sync_block (const std::string &name, gr_io_signature_sptr input_signature, gr_io_signature_sptr output_signature)
Protected Attributes inherited from gr_basic_block
std::string	d_name
gr_io_signature_sptr	d_input_signature
gr_io_signature_sptr	d_output_signature
long	d_unique_id
vcolor	d_color
Protected Attributes inherited from gri_control_loop
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

Detailed Description

Implements a PLL which locks to the input frequency and outputs an estimate of that frequency. Useful for FM Demod.

input: stream of complex; output: stream of floats.

This PLL locks onto a [possibly noisy] reference carrier on the input and outputs an estimate of that frequency in radians per sample. All settings max_freq and min_freq are in terms of radians per sample, NOT HERTZ. The loop bandwidth determins the lock range and should be set around pi/200 – 2pi/100.

See Also

gr_pll_refout_cc, gr_pll_carriertracking_cc

Friends And Related Function Documentation

GR_CORE_API gr_pll_freqdet_cf_sptr gr_make_pll_freqdet_cf ( float  loop_bw, float  max_freq, float  min_freq  )

friend

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

• gr_pll_freqdet_cf.h