Distance of microstrip patch from the ends of the substrate while designing

Hi!
Can anyone please tell the criteria for the distance between the microstrip patch and the ends of the substrate to satisfy the resonant frequency of 2.4GHz?
In the image given, please indicate the rule or formula to calculate the distances a,b and c.

Thanks in advance.

Normally the patch is at the center of your substrate, but that may differ based on your application. So there's no rule for where exactly to place your patch.

For example in mobile phone handsets it's normally the case to place the patch at the complete edge to give better matching, for other applications this may differ.

Your design looks quite normal. So to resonate at 2.4GHz you need to change your dimensions according to the formulas for microstrip patch antennas, or take a look at this post with the automatic calculation of the dimensions for any resonant frequency (but with coaxial feed).

https://www.edaboard.com/thread281995.html