best position for probe in microstrip patch ?

where is the best position for probe if we want best S11 at f0?
Is there any formula?
or we must try and error?

Hi

well if you have any EM simulator you can do parametric analysis and find the best position for the feed. normally it is at L/4 from the edge where L is the resonant length of a square patch


regards

thanks,
but its an approximation.
do you know any paper that discuss parametrically on prob position?

?

well i dont have any specific paper discussing parametric study on probe position but as i said you can easily do this yourself in any EM simulator


thanks

I think its
Z= cos2(ΠYo/L);
Where Yo is the distance from edge of the patch.
L-length of the patch antenna.

Cross check it.

Hi

yes i agree this is the analytical expression for the input impedance variation along the length of the patch.

regards

what are the lengths of marked arm???

it is available at the bottom

sorry,but i think u r not getting my question

see the pic..

plz help

i am also searching many book . iam not getting nswer for this.
some books thay are telling that is equal to microstip feed lind width.W0
i also looking for the detailas. particularly feed design concept. do u have any other idea?

i am also searching many book . iam not getting nswer for this.
some books thay are telling that is equal to microstip feed lind width.W0
i also looking for the detailas. particularly feed design concept. do u have any other idea?