I understand you're interested in computing antenna parameters such as HPBW, FNBW, SLL, directivity, and more using MATLAB. While there isn't a single function that calculates all these parameters, you can use the findLobes function to determine several key characteristics, including:
- HPBW (half-power beamwidth)
- FNBW (first-null beamwidth)
- F/B (front-to-back ratio)
- SLL (side lobe level)
- Main (main lobe peak value and corresponding angle)
- Back (back lobe peak value and corresponding angle)
Below is the example that creates a 15-element ULA of isotropic antenna with elements spaced one-half wavelength apart. Plot the directivity of the array at 20 GHz. Then, find the mainlobe, sidelobe, and backlobe directions of the array pattern.
c = physconst('Lightspeed');
antenna = phased.IsotropicAntennaElement('FrequencyRange',[1.0e9,100.0e9]);
array = phased.ULA('Element',antenna,'NumElements',15,'ElementSpacing',lam/2);
a = pattern(array,fc,angs,0);
P = polarpattern(angs,a);
L = findLobes(P)
L =
mainLobe: [1×1 struct]
backLobe: [1×1 struct]
sideLobes: [1×1 struct]
FB: 0
SLL: 0
HPBW: 8.0000
FNBW: 16.0000
FBIdx: [181 1]
SLLIdx: [181 361]
HPBWIdx: [357 5]
HPBWAng: [176 -176]
FNBWIdx: [173 189]
If you're also interested in learning how to interact with polar plots and view associated metrics, you can refer to the following documentation
For more information on the findLobes function:
Hope it helps!
