Broadband antenna design, 500MHz - 3GHz need info

I am trying to find info on the design of Broadband antenna 500MHz-3GHz , with FR4 PCB (just like the one sold on the Ebay, the log periodic PCB antenna) any design info? how to calculate the size of each elements? or any existing example?

I find "Log Periodic Antenna Design Handbook" Carl E Smith 1966 to be particularly helpful.

A LPD operating from 500 Mhz to 3 GHz souldn't be too hard in FR4. I would expect the base to be a little more than a foot wide and depending on the gain you wand it would be a couple of feet long. A feed of 0.141 semi rigid coax would probably be a good starting point. I have not seen "the one on eBAY".

http://cgi.ebay.com/900-2600-MHz-PCB...742.m153.l1262


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I saw the antennas you referenced on eBAY. If you want to design one use the reference material above.

I would not use their feed with a connector at the apex of the LPD. That has to corrupt the pattern. I don't know your application and this may be just fine.

Or you could just purchase a PCB and go from there. Then good luck.