gr_firdes Class Reference
[Digital Filter Design]

Finite Impulse Response (FIR) filter design functions. More...

#include <gr_firdes.h>

List of all members.

Public Types
enum	win_type {   WIN_HAMMING = 0, WIN_HANN = 1, WIN_BLACKMAN = 2, WIN_RECTANGULAR = 3,   WIN_KAISER = 4 }
Static Public Member Functions
static std::vector< float >	low_pass (double gain, double sampling_freq, double cutoff_freq, double transition_width, win_type window=WIN_HAMMING, double beta=6.76)
	use "window method" to design a low-pass FIR filter
static std::vector< float >	high_pass (double gain, double sampling_freq, double cutoff_freq, double transition_width, win_type window=WIN_HAMMING, double beta=6.76)
	use "window method" to design a high-pass FIR filter
static std::vector< float >	band_pass (double gain, double sampling_freq, double low_cutoff_freq, double high_cutoff_freq, double transition_width, win_type window=WIN_HAMMING, double beta=6.76)
	use "window method" to design a band-pass FIR filter
static std::vector< gr_complex >	complex_band_pass (double gain, double sampling_freq, double low_cutoff_freq, double high_cutoff_freq, double transition_width, win_type window=WIN_HAMMING, double beta=6.76)
	use "window method" to design a complex band-pass FIR filter
static std::vector< float >	band_reject (double gain, double sampling_freq, double low_cutoff_freq, double high_cutoff_freq, double transition_width, win_type window=WIN_HAMMING, double beta=6.76)
	use "window method" to design a band-reject FIR filter
static std::vector< float >	hilbert (unsigned int ntaps=19, win_type windowtype=WIN_RECTANGULAR, double beta=6.76)
	design a Hilbert Transform Filter
static std::vector< float >	root_raised_cosine (double gain, double sampling_freq, double symbol_rate, double alpha, int ntaps)
	design a Root Cosine FIR Filter (do we need a window?)
static std::vector< float >	gaussian (double gain, double spb, double bt, int ntaps)
	design a Gaussian filter
static std::vector< float >	window (win_type type, int ntaps, double beta)

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Detailed Description

Finite Impulse Response (FIR) filter design functions.

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Member Enumeration Documentation

enum gr_firdes::win_type

Enumerator:

WIN_HAMMING
WIN_HANN
WIN_BLACKMAN
WIN_RECTANGULAR
WIN_KAISER

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Member Function Documentation

static std::vector<float> gr_firdes::band_pass	(	double	gain,
		double	sampling_freq,
		double	low_cutoff_freq,
		double	high_cutoff_freq,
		double	transition_width,
		win_type	window = WIN_HAMMING,
		double	beta = 6.76
	)			[static]

use "window method" to design a band-pass FIR filter

gain: overall gain of filter (typically 1.0) sampling_freq: sampling freq (Hz) low_cutoff_freq: center of transition band (Hz) high_cutoff_freq: center of transition band (Hz) transition_width: width of transition band (Hz). The normalized width of the transition band is what sets the number of taps required. Narrow --> more taps window_type: What kind of window to use. Determines maximum attenuation and passband ripple. beta: parameter for Kaiser window

static std::vector<float> gr_firdes::band_reject	(	double	gain,
		double	sampling_freq,
		double	low_cutoff_freq,
		double	high_cutoff_freq,
		double	transition_width,
		win_type	window = WIN_HAMMING,
		double	beta = 6.76
	)			[static]

use "window method" to design a band-reject FIR filter

gain: overall gain of filter (typically 1.0) sampling_freq: sampling freq (Hz) low_cutoff_freq: center of transition band (Hz) high_cutoff_freq: center of transition band (Hz) transition_width: width of transition band (Hz). The normalized width of the transition band is what sets the number of taps required. Narrow --> more taps window_type: What kind of window to use. Determines maximum attenuation and passband ripple. beta: parameter for Kaiser window

static std::vector<gr_complex> gr_firdes::complex_band_pass	(	double	gain,
		double	sampling_freq,
		double	low_cutoff_freq,
		double	high_cutoff_freq,
		double	transition_width,
		win_type	window = WIN_HAMMING,
		double	beta = 6.76
	)			[static]

use "window method" to design a complex band-pass FIR filter

gain: overall gain of filter (typically 1.0) sampling_freq: sampling freq (Hz) low_cutoff_freq: center of transition band (Hz) high_cutoff_freq: center of transition band (Hz) transition_width: width of transition band (Hz). The normalized width of the transition band is what sets the number of taps required. Narrow --> more taps window_type: What kind of window to use. Determines maximum attenuation and passband ripple. beta: parameter for Kaiser window

static std::vector<float> gr_firdes::gaussian	(	double	gain,
		double	spb,
		double	bt,
		int	ntaps
	)			[static]

design a Gaussian filter

gain: overall gain of filter (typically 1.0) symbols per bit: symbol rate, must be a factor of sample rate ntaps: number of taps

static std::vector<float> gr_firdes::high_pass	(	double	gain,
		double	sampling_freq,
		double	cutoff_freq,
		double	transition_width,
		win_type	window = WIN_HAMMING,
		double	beta = 6.76
	)			[static]

use "window method" to design a high-pass FIR filter

gain: overall gain of filter (typically 1.0) sampling_freq: sampling freq (Hz) cutoff_freq: center of transition band (Hz) transition_width: width of transition band (Hz). The normalized width of the transition band is what sets the number of taps required. Narrow --> more taps window_type: What kind of window to use. Determines maximum attenuation and passband ripple. beta: parameter for Kaiser window

static std::vector<float> gr_firdes::hilbert	(	unsigned int	ntaps = 19,
		win_type	windowtype = WIN_RECTANGULAR,
		double	beta = 6.76
	)			[static]

design a Hilbert Transform Filter

ntaps: Number of taps, must be odd window_type: What kind of window to use beta: Only used for Kaiser

static std::vector<float> gr_firdes::low_pass	(	double	gain,
		double	sampling_freq,
		double	cutoff_freq,
		double	transition_width,
		win_type	window = WIN_HAMMING,
		double	beta = 6.76
	)			[static]

use "window method" to design a low-pass FIR filter

gain: overall gain of filter (typically 1.0) sampling_freq: sampling freq (Hz) cutoff_freq: center of transition band (Hz) transition_width: width of transition band (Hz). The normalized width of the transition band is what sets the number of taps required. Narrow --> more taps window_type: What kind of window to use. Determines maximum attenuation and passband ripple. beta: parameter for Kaiser window

static std::vector<float> gr_firdes::root_raised_cosine	(	double	gain,
		double	sampling_freq,
		double	symbol_rate,
		double	alpha,
		int	ntaps
	)			[static]

design a Root Cosine FIR Filter (do we need a window?)

gain: overall gain of filter (typically 1.0) sampling_freq: sampling freq (Hz) symbol rate: symbol rate, must be a factor of sample rate alpha: excess bandwidth factor ntaps: number of taps

static std::vector<float> gr_firdes::window	(	win_type	type,
		int	ntaps,
		double	beta
	)			[static]

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

• gr_firdes.h