navigation.c File Reference

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Detailed Description

GNSS core 'c' function library: navigation functions.

Author:

Glenn D. MacGougan (GDM)

Date:

2007-11-29

Since:

2005-08-23

"LICENSE INFORMATION"
Copyright (c) 2007, refer to 'author' doxygen tags
All rights reserved.

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• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
  
• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
  
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Definition in file navigation.c.

#include <math.h>
#include "constants.h"
#include "geodesy.h"
#include "navigation.h"

Go to the source code of this file.

Functions
void	NAVIGATION_ComputeDerivativesOf_Range_WithRespectTo_XYZ (const double x, const double y, const double z, const double satX, const double satY, const double satZ, double *dPdx, double *dPdy, double *dPdz, double *range)
	Computes the derivative of the pseudorange with respect to X, Y, Z. Also computes the user to satellite range for convenience.
void	NAVIGATION_ComputeDerivativesOf_Range_WithRespectToLatitudeLongitudeHeight (const double latitude, const double longitude, const double height, const double satX, const double satY, const double satZ, double *dlat, double *dlon, double *dhgt, double *range)
	Computes the derivative of the pseudorange with respect to latitude, longitude, and height/ Also computes the user to satellite range for convenience.
int	NAVIGATION_PerformClosedFormPositionSolution_FromPseuodrangeMeasurements (double p1, double p2, double p3, double p4, double prc_satclk1, double prc_satclk2, double prc_satclk3, double prc_satclk4, double x1, double x2, double x3, double x4, double y1, double y2, double y3, double y4, double z1, double z2, double z3, double z4, double *latitude, double *longitude, double *height, double *rx_clock_bias)
	Compute a closed form position solution using four raw pseudoranges.

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Function Documentation

void NAVIGATION_ComputeDerivativesOf_Range_WithRespectTo_XYZ	(	const double	x,
		const double	y,
		const double	z,
		const double	satX,
		const double	satY,
		const double	satZ,
		double *	dPdx,
		double *	dPdy,
		double *	dPdz,
		double *	range
	)

Computes the derivative of the pseudorange with respect to X, Y, Z. Also computes the user to satellite range for convenience.

Author:

Glenn D. MacGougan (GDM)

Date:

2005-08-23

Since:

2005-08-23

Parameters:

x	User X coordinate WGS84 ECEF [m]
y	User Y coordinate WGS84 ECEF [m]
z	User Z coordinate WGS84 ECEF [m]
satX	Satellite X coordinate WGS84 ECEF [m]
satY	Satellite Y coordinate WGS84 ECEF [m]
satZ	Satellite Z coordinate WGS84 ECEF [m]
dPdx	Derivative of P wrt X []
dPdy	Derivative of P wrt Y []
dPdz	Derivative of P wrt Z []
range	computed user to satellite range [m]

Definition at line 42 of file navigation.c.

void NAVIGATION_ComputeDerivativesOf_Range_WithRespectToLatitudeLongitudeHeight	(	const double	latitude,
		const double	longitude,
		const double	height,
		const double	satX,
		const double	satY,
		const double	satZ,
		double *	dlat,
		double *	dlon,
		double *	dhgt,
		double *	range
	)

Computes the derivative of the pseudorange with respect to latitude, longitude, and height/ Also computes the user to satellite range for convenience.

Author:

Glenn D. MacGougan (GDM)

Date:

2005-08-23

Since:

2005-08-23

Parameters:

latitude	User geodetic latitude [rad]
longitude	User geodetic longtiude [rad]
height	User geodetic height [m]
satX	Satellite X coordinate WGS84 ECEF [m]
satY	Satellite Y coordinate WGS84 ECEF [m]
satZ	Satellite Z coordinate WGS84 ECEF [m]
dlat	d(P)/d(lat) but not in units of [m/rad], [m/m]
dlon	d(P)/d(lon) but not in units of [m/rad], [m/m]
dhgt	d(P)/d(hgt) [m/m]
range	computed user to satellite range [m]

Definition at line 73 of file navigation.c.

int NAVIGATION_PerformClosedFormPositionSolution_FromPseuodrangeMeasurements	(	double	p1,
		double	p2,
		double	p3,
		double	p4,
		double	prc_satclk1,
		double	prc_satclk2,
		double	prc_satclk3,
		double	prc_satclk4,
		double	x1,
		double	x2,
		double	x3,
		double	x4,
		double	y1,
		double	y2,
		double	y3,
		double	y4,
		double	z1,
		double	z2,
		double	z3,
		double	z4,
		double *	latitude,
		double *	longitude,
		double *	height,
		double *	rx_clock_bias
	)

Compute a closed form position solution using four raw pseudoranges.

Author:

Glenn D. MacGougan (GDM)

Date:

2005-08-23

Since:

2005-08-23

Returns:

TRUE(1) if successful, FALSE(0) otherwise.

Remarks:

(1) The satellite clock corrections in meters are required for each pseudorange
(2) This function was written for easy portability into Matlab

REFERENCES
[1] Mezentsev, O. and J. Collin (2004). A Closed Form Solution Of Non-Linear GPS Pseudorange Equations. White paper proof - not published.

Parameters:

p1	1st raw pseudorange measurement [m]
p2	2nd raw pseudorange measurement [m]
p3	3rd raw pseudorange measurement [m]
p4	4th raw pseudorange measurement [m]
prc_satclk1	1st satellite clock corrections for psuedoranges [m]
prc_satclk2	2nd satellite clock corrections for psuedoranges [m]
prc_satclk3	3rd satellite clock corrections for psuedoranges [m]
prc_satclk4	4th satellite clock corrections for psuedoranges [m]
x1	1st satellite X coordinates, WGS84 ECEF [m]
x2	2nd satellite X coordinates, WGS84 ECEF [m]
x3	3rd satellite X coordinates, WGS84 ECEF [m]
x4	4th satellite X coordinates, WGS84 ECEF [m]
y1	1st satellite Y coordinates, WGS84 ECEF [m]
y2	2nd satellite Y coordinates, WGS84 ECEF [m]
y3	3rd satellite Y coordinates, WGS84 ECEF [m]
y4	4th satellite Y coordinates, WGS84 ECEF [m]
z1	1st satellite Z coordinates, WGS84 ECEF [m]
z2	2nd satellite Z coordinates, WGS84 ECEF [m]
z3	3rd satellite Z coordinates, WGS84 ECEF [m]
z4	4th satellite Z coordinates, WGS84 ECEF [m]
latitude	The computed geodetic latitude [rad]
longitude	The computed geodetic longitude [rad]
height	The computed geodetic height [m]
rx_clock_bias	The computed receiver clock bias [m]

Definition at line 150 of file navigation.c.