I have been playing with various antenna modelers (EZNEC, MMANA-gal, 4nec2) and I keep finding the same (counter-intutive) thing. Imagine a simple 5 wire 2m Ground Plane antenna in free-space where the four resonant radials are horizontal.
Wouldn't you expect that the maximum radiation would be a few (maybe 30) degrees above the plane of the radials, kind of like a 1/4λ monopole against a real ground.
All of the NEC2 based engines show max radiation at zero degrees, and the 3-d pattern shows a perfect donut with symmetry along the Z-axis, just like a free-space vertical 1/2λ dipole would have.
Seems counter-intuitive to me. I would expect that the four orthogonal radials should cause the peak radiation point to move upwards from 0 degrees. Is this a limitation of the NEC2 algorithm, or is this a real behavior?
Wouldn't you expect that the maximum radiation would be a few (maybe 30) degrees above the plane of the radials, kind of like a 1/4λ monopole against a real ground.
All of the NEC2 based engines show max radiation at zero degrees, and the 3-d pattern shows a perfect donut with symmetry along the Z-axis, just like a free-space vertical 1/2λ dipole would have.
Seems counter-intuitive to me. I would expect that the four orthogonal radials should cause the peak radiation point to move upwards from 0 degrees. Is this a limitation of the NEC2 algorithm, or is this a real behavior?