Hi ankitbende,
Admittedly I still don't understand what you're trying to achieve, but regardless, it seems like your issue is the impedance bandwidth of the patch antenna. Some form of matching can most likely be accomplished at the feed.
Since you are using coaxial connectors, I would attempt to change the radius of the dielectric cutout around the pins which connect to the patch. I've found that this provides a subtle shift in the loading impedance, and may solve your problem.
Good Luck