itpp::Rice_Fading_Generator Class Reference
[Channel Modeling]

Rice type fading generator class. More...

#include <channel.h>

List of all members.

Public Member Functions

Rice_Fading_Generator (double norm_doppler, DOPPLER_SPECTRUM spectrum=Jakes, int no_freq=16, RICE_METHOD method=MEDS)

Default constructor.

virtual ~Rice_Fading_Generator ()

Destructor.

virtual void set_doppler_spectrum (DOPPLER_SPECTRUM spectrum)

Set Doppler spectrum.

virtual void set_no_frequencies (int no_freq)

Set number of Doppler frequencies.

virtual void set_rice_method (RICE_METHOD method)

Set calculation method of Doppler frequencies and amplitudes.

virtual DOPPLER_SPECTRUM get_doppler_spectrum () const

Return Doppler spectrum.

virtual int get_no_frequencies () const

Get number of Doppler frequencies.

virtual RICE_METHOD get_rice_method () const

Get calculation method of Doppler frequencies and amplitudes.

virtual void init ()

Initialize the generator.

virtual void generate (int no_samples, cvec &output)

Generate no_samples values from the fading process.

virtual void set_norm_doppler (double norm_doppler)

Set normalized Doppler.

virtual void set_LOS_doppler (double relative_doppler)

Set relative Doppler (compared to the maximum Doppler) for the LOS component.

virtual void set_time_offset (int offset)

Set time offset in samples.

virtual double get_norm_doppler () const

Return normalized Doppler.

virtual double get_LOS_doppler () const

Get relative Doppler (compared to the maximum doppler) for the LOS component.

virtual double get_time_offset () const

Get time offset in samples.

virtual void shift_time_offset (int no_samples)

Shift generator time offset by a number of samples.

cvec generate (int no_samples)

Generate no_samples values from the fading process.

void set_LOS_power (double relative_power)

Set relative LOS power.

virtual void set_filter_length (int filter_length)

Set FIR filter length (for FIR fading generator).

double get_LOS_power () const

Get relative power of LOS component (Rice factor).

virtual int get_filter_length () const

Set FIR filter length (for FIR fading generator).

Protected Member Functions

void init_MEDS ()

Init function for MEDS method.

void add_LOS (int idx, std::complex< double > &sample)

add LOS component to the sample with index idx

Protected Attributes

DOPPLER_SPECTRUM dopp_spectrum

int Ni

Number of sine waves in a Gaussian process.

RICE_METHOD rice_method

Rice process generation method.

double n_dopp

Normalized maximum Doppler frequency.

double los_dopp

Relative Doppler on LOS component (0.7 by default).

double time_offset

Time offset in samples (time state in the generator).

bool init_flag

signals if generator is initialized or not

double los_power

Relative power of LOS component compared to diffuse component (K factor).

double los_diffuse

Diffuse component: sqrt(1 / (1 + los_power)).

double los_direct

Direct component: sqrt(los_power / (1 + los_power)).

vec f1

vec f2

vec c1

vec c2

vec th1

vec th2

double f01

double f02

Detailed Description

Rice type fading generator class.

Author:: Tony Ottosson, Adam Piatyszek and Zbigniew Dlugaszewski

A Rice generator is a generator of the form:

$\tilde \mu_i(t) = \sum_{n=1}^{N_i} c_{i,n} \cos(2\pi f_{i,n} t + \theta_{i,n})$

Here $c_{i,n}$ , $f_{i,n}$ , and $\theta_{i,n}$ are the Doppler coefficients, discrete Doppler frequencies, and Doppler phases, respectively. Rice showed that a generator of this form can perfectly model a Gaussian process when $N_i \rightarrow \infty$ . When generating a fading pattern we need a complex-valued generator

$\tilde \mu(t) = \tilde \mu_1(t) + j \tilde \mu_2(t)$

Parameters that define the generator are the normalized Doppler and the doppler spectrum. Possible values of the Doppler spectrum are:

Jakes, J, Classic, C: The classical Jakes spectrum shape. This method can be also used for modelling LOS paths, by setting the LOS relative power (Rice factor) and LOS Doppler parameters.
GaussI, GI, Gauss1, G1
GaussII, GII, Gauss2, G2

Furthermore also the number of sine waves, $ N_i $ and method used to calculate the parameters $c_{i,n}$ , $f_{i,n}$ , and $\theta_{i,n}$ can be specified. For now the only method defined for calculating the parameters is the Method of Exact Doppler Spread (MEDS). See [Pat02] for more details.

References:

[Pat02] Matthias Patzold, Mobile fading channels, Wiley, 2002.

Member Data Documentation

DOPPLER_SPECTRUM itpp::Rice_Fading_Generator::dopp_spectrum [protected]

Doppler spectrum type (Jakes by default)

Referenced by generate(), get_doppler_spectrum(), init_MEDS(), and set_doppler_spectrum().

double itpp::Rice_Fading_Generator::f01 [protected]

Frequency shift values of the Doppler spectrum in GaussI and GaussII

Referenced by generate(), and init_MEDS().

vec itpp::Rice_Fading_Generator::f1 [protected]

Doppler frequencies, amplitudes and phases

Referenced by generate(), and init_MEDS().

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


Public Member Functions
	Rice_Fading_Generator (double norm_doppler, DOPPLER_SPECTRUM spectrum=Jakes, int no_freq=16, RICE_METHOD method=MEDS)
	Default constructor.
virtual	~Rice_Fading_Generator ()
	Destructor.
virtual void	set_doppler_spectrum (DOPPLER_SPECTRUM spectrum)
	Set Doppler spectrum.
virtual void	set_no_frequencies (int no_freq)
	Set number of Doppler frequencies.
virtual void	set_rice_method (RICE_METHOD method)
	Set calculation method of Doppler frequencies and amplitudes.
virtual DOPPLER_SPECTRUM	get_doppler_spectrum () const
	Return Doppler spectrum.
virtual int	get_no_frequencies () const
	Get number of Doppler frequencies.
virtual RICE_METHOD	get_rice_method () const
	Get calculation method of Doppler frequencies and amplitudes.
virtual void	init ()
	Initialize the generator.
virtual void	generate (int no_samples, cvec &output)
	Generate no_samples values from the fading process.
virtual void	set_norm_doppler (double norm_doppler)
	Set normalized Doppler.
virtual void	set_LOS_doppler (double relative_doppler)
	Set relative Doppler (compared to the maximum Doppler) for the LOS component.
virtual void	set_time_offset (int offset)
	Set time offset in samples.
virtual double	get_norm_doppler () const
	Return normalized Doppler.
virtual double	get_LOS_doppler () const
	Get relative Doppler (compared to the maximum doppler) for the LOS component.
virtual double	get_time_offset () const
	Get time offset in samples.
virtual void	shift_time_offset (int no_samples)
	Shift generator time offset by a number of samples.
cvec	generate (int no_samples)
	Generate no_samples values from the fading process.
void	set_LOS_power (double relative_power)
	Set relative LOS power.
virtual void	set_filter_length (int filter_length)
	Set FIR filter length (for FIR fading generator).
double	get_LOS_power () const
	Get relative power of LOS component (Rice factor).
virtual int	get_filter_length () const
	Set FIR filter length (for FIR fading generator).
Protected Member Functions
void	init_MEDS ()
	Init function for MEDS method.
void	add_LOS (int idx, std::complex< double > &sample)
	add LOS component to the sample with index idx
Protected Attributes
DOPPLER_SPECTRUM	dopp_spectrum
int	Ni
	Number of sine waves in a Gaussian process.
RICE_METHOD	rice_method
	Rice process generation method.
double	n_dopp
	Normalized maximum Doppler frequency.
double	los_dopp
	Relative Doppler on LOS component (0.7 by default).
double	time_offset
	Time offset in samples (time state in the generator).
bool	init_flag
	signals if generator is initialized or not
double	los_power
	Relative power of LOS component compared to diffuse component (K factor).
double	los_diffuse
	Diffuse component: sqrt(1 / (1 + los_power)).
double	los_direct
	Direct component: sqrt(los_power / (1 + los_power)).

vec	f1
vec	f2
vec	c1
vec	c2
vec	th1
vec	th2

double	f01
double	f02

itpp::Rice_Fading_Generator Class Reference [Channel Modeling]

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Member Data Documentation

itpp::Rice_Fading_Generator Class Reference
[Channel Modeling]