# surfclutterrcs

Surface clutter radar cross section (RCS)

## Syntax

RCS = surfclutterrcs(NRCS,R,az,el,graz,tau)
RCS = surfclutterrcs(NRCS,R,az,el,graz,tau,c)

## Description

RCS = surfclutterrcs(NRCS,R,az,el,graz,tau) returns the radar cross section (RCS) of a clutter patch that is of range R meters away from the radar system. az and el are the radar system azimuth and elevation beamwidths, respectively, corresponding to the clutter patch. graz is the grazing angle of the clutter patch relative to the radar. tau is the pulse width of the transmitted signal. The calculation automatically determines whether the surface clutter area is beam limited or pulse limited, based on the values of the input arguments.

RCS = surfclutterrcs(NRCS,R,az,el,graz,tau,c) specifies the propagation speed in meters per second.

## Input Arguments

 NRCS Normalized radar cross section of clutter patch in units of square meters/square meters. R Range of clutter patch from radar system, in meters. az Azimuth beamwidth of radar system corresponding to clutter patch, in degrees. el Elevation beamwidth of radar system corresponding to clutter patch, in degrees. graz Grazing angle of clutter patch relative to radar system, in degrees. tau Pulse width of transmitted signal, in seconds. c Propagation speed, in meters per second. Default: Speed of light

## Output Arguments

 RCS Radar cross section of clutter patch.

## Examples

collapse all

Calculate the RCS of a clutter patch and estimate the clutter-to-noise ratio (CNR) at the receiver. Assume that the patch has a normalized radar cross section (NRCS) of 1 m²/m² and is 1.0 km away from the radar system. The azimuth and elevation beamwidths are 1° and 3°, respectively. The grazing angle is 10°. The pulse width is 10μs. The radar operates at a wavelength of 1 cm with a peak power of 5 kW.

nrcs = 1;
rng = 1.0e3;
az = 1;
el = 3;
graz = 10;
tau = 10e-6;
lambda = 0.01;
ppow = 5000;
rcs = surfclutterrcs(nrcs,rng,az,el,graz,tau)
rcs = 5.2627e+03
cnr = 75.2006

## Tips

• You can calculate the clutter-to-noise ratio using the output of this function as the RCS input argument value in radareqsnr.

See [1].

## References

[1] Richards, M. A. Fundamentals of Radar Signal Processing. New York: McGraw-Hill, 2005, pp. 57–63.