aer2ned

Transform local spherical coordinates to local north-east-down

Syntax

[xNorth,yEast,zDown] = aer2ned(az,elev,slantRange)

[___] = aer2ned(___,angleUnit)

Description

[xNorth,yEast,zDown] = aer2ned(az,elev,slantRange) transforms the local spherical azimuth-elevation-range (AER) coordinates specified by az, elev, and slantRange to the local north-east-down (NED) coordinates specified by xNorth, yEast, and zDown. Both coordinate systems use the same local origin. Each input argument must match the others in size or be scalar.

[___] = aer2ned(___,angleUnit) specifies the units for azimuth and elevation. Specify angleUnit as 'degrees' (the default) or 'radians'.

Examples

Calculate NED Coordinates from AER Coordinates

A sensor in an aircraft measures the AER coordinates of a nearby landmark. Find the NED coordinates of the landmark with respect to the aircraft, using the AER coordinates of the landmark with respect to the same aircraft.

First, specify the AER coordinates of the landmark. Specify the azimuth and elevation in degrees. For this example, specify the slant range in kilometers.

az = 155.427;
elev = -23.161;
slantRange = 10.885;

Then, calculate the NED coordinates of the landmark. The units for the NED coordinates match the units specified by the slant range. Thus, the NED coordinates are specified in kilometers.

[xNorth,yEast,zDown] = aer2ned(az,elev,slantRange)

xNorth = 
-9.1013

yEast = 
4.1617

zDown = 
4.2812

Reverse the transformation using the ned2aer function.

[az,elev,slantRange] = ned2aer(xNorth,yEast,zDown)

az = 
155.4270

elev = 
-23.1610

slantRange = 
10.8850

Input Arguments

az — Azimuth angles

scalar | vector | matrix | N-D array

Azimuth angles of one or more points in the local AER system, specified as a scalar, vector, matrix, or N-D array. Azimuths are measured clockwise from north. Specify values in degrees. To use values in radians, specify the angleUnit argument as 'radians'.

Data Types: single | double

elev — Elevation angles

scalar | vector | matrix | N-D array

Elevation angles of one or more points in the local AER system, specified as a scalar, vector, matrix, or N-D array. Specify elevations with respect to the xNorth-yEast plane that contains the local origin. If the local origin is on the surface of the spheroid, then the xNorth-yEast plane is tangent to the spheroid.

Specify values in degrees. To use values in radians, specify the angleUnit argument as 'radians'.

Data Types: single | double

slantRange — Distances from local origin

scalar value | vector | matrix | N-D array

Distances from the local origin, specified as a scalar, vector, matrix, or N-D array. Specify each distance as along a straight, 3-D, Cartesian line.

Data Types: single | double

angleUnit — Angle units

'degrees' (default) | 'radians'

Angle units, specified as 'degrees' (the default) or 'radians'.

Output Arguments

xNorth — NED x-coordinates

scalar | vector | matrix | N-D array

NED x-coordinates of one or more points in the local NED system, returned as a scalar, vector, matrix, or N-D array. Values are returned in the same units as the slantRange argument.

yEast — NED y-coordinates

scalar | vector | matrix | N-D array

NED y-coordinates of one or more points in the local NED system, returned as a scalar, vector, matrix, or N-D array. Values are returned in the same units as the slantRange argument.

zDown — NED z-coordinates

scalar | vector | matrix | N-D array

NED z-coordinates of one or more points in the local NED system, returned as a scalar, vector, matrix, or N-D array. Values are returned in the same units as the slantRange argument.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

Version History

Introduced in R2012b

R2021a: Generate C and C++ code using MATLAB Coder

The aer2ned function supports code generation.