Because of the high maintenance needed to monitor and filter spammers from the RF Cafe Forums, I decided that it would
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Below are all of the forum threads, including all
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Post subject: High Frequency/High Perm CP antenna
Posted: Mon Nov 06, 2006 12:12 pm
Joined: Wed Jul 20, 2005 9:59 am
I am trying to design a CP patch antenna at 24 GHz. The antenna is to be fed by CPW and is EM coupled into the patch on the other side. The substrate that I am using has a high permitivity value of 12.9. I am using HFSS and would consider myself an experienced user so I am confident the of the values of axial ratio I am getting (which is at best about 10dB)
I have tried chopping the corners, alternating the angle of the feed, alternating the type of feed (cap or inductive), putting slots in the patch but all to no avail. Is there something fundamental I am missing that means I can't generate CP with the parameters set out above.