spiral antenna design

hi
I want to knw if somebody can guide me the design parameters for square spiral antenna? I have to design a square spiral microstrip antenna in HFSS. I need to know wht does the arm length , thickness of strip, substrate height etc affect the design parameters of the antenna like frequency gain beam width etc. please help me in this regard as i feel stuck in finding the rite material on it ..
Regards
Safwat

Spiral antennas are a class of antenna that are rotational symmetric. Only one part of the antenna radiates at any frequency. The radiation is perpendicular to the plane of the antenna.

Making it square will degrade this performance since there will be discontinuities in the rotation symmetry. This is because the corners and the parallel nature of the turns.

I would suspect that you will have an alternating set of passbands and stop bands.

Thanks, flatulent . But you didn't specified How the Design Parameters can be used ?

The spacing and trace width should increase as you go from the feed point down the traces to the free ends. This increase on round versions is a mathematical function of the rotating angle.

I have never seen a square version as round versions will fit in the same space.

you can use the file from this link:

https://www.edaboard.com/viewtopic.p...9117&highlight

hi
its an old post but still if you look it then can you tell me in log spiral that rotating angle is phi or delta?bkz phi is taken as any value from 0-2pi but delta is normally taken as 90 for complementry op so which is rotation angle plzz do reply