a Matlab package for phased array beam shape inspection

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C. Matlab functions
There are two types of m-files in the e3ant directory: m-files that produce plots, and
m-files that don’t. The plotting files have simple headers and do not usually allow
parameter input on the command line. Instead, they require that the input parameters
be hardcoded in the files themselves. Plotting normally requires so much parameters
and fine-tuning that putting all that info into call parameter list is impractical. Thus,
the files must be manipulated, but I have made an effort to indicate what can be safely
modified. The other group of m-files perform some clearly defined computation and have
normal parametrized headers, and the normal Matlab help should work usefully in their
case.
Plotting functions
• beamshape2d — Plot beam’s 2D cross section.
• beamsteering — Plot beam direction as a function of phasing angle.
• common volume — Compute and plot the size of the effective scattering volume.
• planearray — Plot array gain in V-plane at any azimuth.
• planearray-jitter — Plot beam shape jitter distributions.
• plot maxgain — Plot maximum available gain (the element’s gain) and the vertical
beamwidth as function of elevation.
• simplebeam — Plot the cos n (θ/2) gain pattern.
• sitegeom1 — Plot a sites’s pointing directions for certain Tromsø beam directions.
Computation-only functions
• arraygain Compute array factor and element gain in arbitrary directions.
• beamwidth Compute vertical beam width of an array.
• grating dir Compute an array’s grating beam directions.
• powerint Computes an array’s directivity and power integral.
• simplegain Compute an element’s normalized gain assuming cos n (θ/2) shape.
• simple vhfbeam Gaussian approximation to VHF antenna beam shape.
• testarray snr Compute the expected SNR for the test array.