the calculation (HDL_ANT2_WinForms by W1GHZ) for my offset dish pruduced following results:
- f/D = 0,36, illumination small axis = 68,1deg and a recommendation for -3dB beamwidth = 38,8deg.
With that in mind various helices were calculated. The best result was with 9turns:
So far,this result does not match the recommendation. Compared with all the publications in the net and here in the forum the amout of turns is more or less doubled. I also couldn`t find any discussion about matching the helix and dish illumination. It is clear that this should match, but nobody does take care of this subject.
Further more, I think that a patch antenna will not be acceptable for this f/D because of the broad overspill.
My concern is, that such a helix will creat troubles with my neighbors wlan.
What are your experience and recommendations