UniformCn2

MATLAB

Cn2 = UniformCn2(h,C0)
Cn2 = UniformCn2(h,PARAM,ParamValue,lambda,G,x,dx,[xRange])

Description

Returns the value of a uniform (constant) Cn2 value over a propagation path given an input value C0, or given a specified atmospheric parameter, its value, and the wavelength, range, and (if applicable) the set of discrete turbulence phase screens for which the parameter value was calculated. UniformCn2 is a function of altitude h to work with ATMTools framework, and returns a Cn2 vector the size(h), but the Cn2 value returned is constant with respect to altitude variation.

Parameters

Parameters	Description
h [vector]	Altitude above earth's surface (m)
C0 [scalar]	Constant Cn2 value for propagation path (${m}^{-2/3}$)
PARAM [string]	Identifier for atmospheric propagation parameter to be specified to determine value of uniform turbulence. Can be set to 'r0', 'rytov', or 'theta0'
ParamValue [scalar]	Numerical value of the atmospheric propagation parameter specified for uniform turbulence.
lambda [scalar]	Wavelength at which specified propagation parameter value was computed (m)
G [struct/scalar]	Geometry structure from GeomStruct or propagation path length for which specified propagation parameter value was computed (m)
x [vector]	For discrete turbulence model, the normalized location of phase screens at which turbulence is introduced along propagation path (m)
dx [vector]	For discrete turbulence model, the normalized thickness of phase screens for turbulence introduced along propagation path (m)
xRange [vector]	(Optional) Normalized range over which input x and dx are normalized. Defaults to [0 1].

Return Values

Return Values	Description
Cn2 [vector]	Index of refraction structure coefficient (${m}^{-2/3}$). Returned as vector size(h).

Examples

Cn2 = UniformCn2(h,5e-17)
- returns constant Cn2 value of $5e-17$ at points along propagation path specified by h
Cn2 = UniformCn2(h,'r0',0.10,1e-6,50000)
- returns constant Cn2 value giving $r_0$ of 0.10 m at 1 micron wavelength for 50 km propagation path using continuous model
Cn2 = UniformCn2(h,'r0',0.10,1e-6,50000,[0.1,0.3,0.5,0.7,0.9],[.2,.2,.2,.2,.2])
- returns constant Cn2 value giving $r_0$ of 0.10 m at 1 micron wavelength for 50 km propagation path using discrete 5-bin model
Cn2 = UniformCn2(h,'r0',0.10,1e-6,50000,[0.1,0.3,0.5,0.7,0.9],[.1,.1,.1,.1,.1])
- returns constant Cn2 value giving $r_0$ of 0.10 m at 1 micron wavelength for 50 km propagation path using discrete 5-bin model for which turbulence does not fill the entire propagation volume.
Atm = AtmStruct(100000,50,10000,20,'MaxAlt',30000,'Cn2','UniformCn2','r0',0.1,1e-6,'L','x','dx','xRange');
- Setup an Atm structure using UniformCn2. Input of xRange is optional, it will be added if needed