Geddes on Waveguides

Can you explain what rounding this is? It might help me solve some issues using AxiDriver.

AxiDriver is ok - I just put wrong number that was rounded in Excel to zero Delta_Z.

Enclosed normalized (to 0 deg) directivity plot.
 

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Good job, jzagaja,
*if* - for one reason or another – you'd like to stick with that particular driver and do not like to take a ring radiator with sufficient displacement instead, I'd like to see a simu with the inner ring of that driver covered by a phase plug reaching out to the mouth of the horn - meaning you close and extend the middle phase plug .

In praxis you could make that phase plug hollow - slide it over the middle phase plug (the ring shaped one) - stuff it heavily, to absorb what's coming from the inner ring.
Sure - you will lose some of the active membrane area but not *that* much IMO (rough guess : 75% still active).

If simu is any good, you then could go on checking out if tweaking the contour of the looooong phase plug is worth the effort.

Michael
 
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AxiDriver is ok - I just put wrong number that was rounded in Excel to zero Delta_Z.

Enclosed normalized (to 0 deg) directivity plot.

Jack

I don't think that you understand how a phase plug works. What you have drawn are all incorrect or if they are modeled from a real device are very bad designs. The cross sectional areas must be a smoothely varying continuos function of the propagation path and should conform to the waveguide flare all the back to the diapragm (which of course is never the case - they are virtually always conical). Yours do not do that, the cross section area changes abruptly at the end of the plug.