>Problem is that he does not show how he arrives at the non quadrature
>phasing numbers of 0, -116, -232 etc.
>Can anyone supply more data on how these results were obtained?
I believe the quadrature phasing is referred to as
cophasal in antenna textbooks, and the more aggressive
phasing is referred to as Hansen-Woodyard phasing.
Basically, just model the array on EZNEC starting with
the quadrature phasing and then increase it 10% at a time:
first 90 deg per element, then 100 deg, then 110 deg etc.
You will see that gain goes up but also the sidelobe
level goes up. Depending on what your other design
constraints are, you can stop wherever necessary along
this curve. I have found as a general rule that 30%
excess phase is usually a good number. The phasings
you mentioned are about 30% over cophasal.
If you used too much phase slope, the sidelobes get
really big and the design becomes impractically critical.
Rick Karlquist N6RK
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