wide bandwidth and wide beamwidth patch antenna

hi...i want to design a patch antenna with 12% bandwidth and 120 degree beamwidth..so far i ve achieved 115 degree beamwidth and 8.8% bandwidth with meander line element on a rtduroid substrate (er=2.2) n i have also introduced an airgap of 25.4mm between ground and substrate..freq of operation is L band
how can i improve my bandwidth without reducing the beamwidth?
anybody please help me out...

Hi Divya.S

Bandwidth can be increased creating more than one resonance.
Aperture-coupled patch is a suitable feeding method that allows this. How are you feeding the patch?
Other methods are stacked patches and coplanar parasitic elements, among others.
Look for chapter 9 of "Microstrip Antenna Design Handbook" by Garg, Bhartia, Bahl, and Ittipiboon (Artech House, 2001).
Regards

Z

Thanks :) i will try with aperture coupled patch..i used coaxial probe feeding..With aperture coupled antenna,can i get that 120 degree beamwidth?

Beamwidth does not depend strongly of the feeding method, but mainly of the geometry.
Take into account that beamwidth is different in the E and H planes.
Regards

Z