Help me with designing circular patch antenna (1.5-1.7 GHz)

[guytoub]

cicular patch antenna

hello everybody!

i want to made a patch circular antenna which work between 1.5GHz and 1.7 GHz
which design can i use?

how can i put the feed to have a good impedance?

thanks

 

[biff44]

Re: cicular patch antenna

You mean circularly polarized? I have seen very simple structures that do that, just a big square of copper on a board, ground plane on the backside, and a flexible coax line fed off-center to the copper square. I have some at 2.4 GHz, I could measure the dimensions if you want.

 

[guytoub]

Re: cicular patch antenna

yes i wanted to say circular polarized! thank for your answer .
if you have the measures of the dimensions i want!

thanks a lot

 

[biff44]

Re: cicular patch antenna

Board is 2.1 by 2.1 inches, ground plane on back. Metal square on the top is 1.65 x 1.65 inches. Hole is offset in top square, along the center in X axis, and 0.305 inches down from the top of the metal square in the Y axis. Material appears to be G10, and is around 0.059 inches thick. There is a 0.125 by 0.125 inch 45 degree chamfer missing from the left top and right bottom of the metal square. Antenna works at 2.45 GHz, so you will have to scale things larger for your frequency band.

I have no clue if it is RH or LH circularly polarized, but is one of those.

 

[wusen]

Re: cicular patch antenna

hi..
The single feed scheme cannot satisfy your bandwidth(1.5~1.7G) demand in generally. You should adopt the dual-orthogonal feed using a power divider. there are many schemes can be find in IEEE papers.

 

[biff44]

Re: cicular patch antenna

Could be, the antenna I have only works over a 100 MHz bandwidth. His is around 3 times bigger percentagewise.

 

[guytoub]

Re: cicular patch antenna

thank to you all for your explanation i'm going to make a test .