physconst
Physical constants
Syntax
Description
Examples
Convert Frequency to Wavelength
Determine the wavelength of a 1 GHz electromagnetic wave.
freq = 1e9;
lambda = physconst('LightSpeed')/freq
lambda = 0.2998
Thermal Noise Power
Determine the thermal noise power per unit bandwidth in the in-phase (I) and quadrature (Q) channels of a receiver. Specify a receiver temperature of 290 K.
T = 290;
k = physconst('Boltzmann');
Compute the noise power per unit bandwidth, split evenly between the I and Q channels. Units are in dB.
Noise_power = 10*log10(k*T/2)
Noise_power = -206.9855
Input Arguments
name
— Name of physical constant
'LightSpeed'
| 'Boltzmann'
| 'EarthRadius'
Name of physical constant, specified as 'LightSpeed'
,
'Boltzmann'
, or 'EarthRadius'
. See Physical Constants for a list of values
for physical constants used in Phased Array System Toolbox™.
Example: 'LightSpeed'
Output Arguments
const
— Value of physical constant
real-valued scalar
Value of physical constant, returned as a real-valued scalar. All values are in SI units.
More About
Physical Constants
This table lists the supported constants and their values in SI units.
Constant | Description | Value |
---|---|---|
'LightSpeed' | Speed of light in vacuum | 299,792,458 m/s. CODATA value commonly denoted by c. |
'Boltzmann' | Boltzmann constant relating kinetic energy to temperature | J/K. CODATA value commonly denoted by k. |
'EarthRadius' | Mean radius of the Earth | 6,371,000 m |
Extended Capabilities
C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.
The function does not support variable-size inputs.
Version History
Introduced in R2011a
See Also
External Websites
MATLAB 명령
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