speed2dop

Convert speed to Doppler shift

Syntax

dps = speed2dop(radvel,lambda)

Description

dps = speed2dop(radvel,lambda) returns the one-way Doppler shift in hertz corresponding to the radial velocity radvel for the wavelength lambda.

Examples

Calculate Doppler Shift from Speed

Calculate the Doppler shift in hertz for a given carrier wavelength and source speed. The radar frequency is 24.15 GHz. Assume a radial speed of 35.76 m/s.

radvel = 35.76;
f0 = 24.15e9;
lambda = physconst('LightSpeed')/f0;
doppler_shift = speed2dop(radvel,lambda)

doppler_shift = 
2.8807e+03

Input Arguments

radvel — Radial velocity

scalar | vector | matrix

Radial velocity in meters per second, specified as a scalar, vector, or matrix.

Data Types: double

lambda — Wavelength

positive scalar

Wavelength in meters, specified as a positive scalar.

Data Types: double

Output Arguments

dps — One-way Doppler shift

scalar | vector | matrix

One-way Doppler shift in hertz, returned as a scalar, vector, or matrix.

More About

Doppler-Radial Velocity Relation

The Doppler shift of a source relative to a receiver can be computed from the relative radial velocity between the source and receiver:

$$\Delta f=\frac{V_{s,r}}{\lambda }$$

where Δf is the Doppler shift in hertz, V_s,r denotes the radial velocity of the source relative to the receiver, and λ is the carrier frequency wavelength in meters.

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using MATLAB® Coder™.

Usage notes and limitations:

Does not support variable-size inputs.

References

[1] Rappaport, T. Wireless Communications: Principles & Practices. Upper Saddle River, NJ: Prentice Hall, 1996.

[2] Skolnik, M. Introduction to Radar Systems, 3rd Ed. New York: McGraw-Hill, 2001.

Version History

Introduced in R2011a