cavity backed antenna

can any body tell me how to design wide beamwidth (>120 deg) wide bandwidth (>1 GHz) in X-band with low cross-polarization cavity backed antenna asap
its urgent guys

ashutosh.kedar@gmail.com

I once used a cavity backed slot (3/8 wavelength gnd spacing) that obtained an 88 deg beamwith and 10% bandwidth at 9GHz.

problem i am facing is of high cross-polarization can u suggest something

I need the help or ur design stuff if u can send at

mian.abdulrazzaq@yahoo.com

You can start with these dimensions and experiment from there:

material: 0.254mm brass

slot dimensions: 16mm x0.8mm

feed tap from end of slot: approx 3mm

gnd spacing: approx 8.5mm

cavity extends approx 1/4 wavelength parallel to slot

Thanks for replying
I dont want slot antenna i want patch antenna supported by a cavity

can u send me something on that or some good papers u have:D

If you are using a patch, why do you need a cavity? are there absorbing material in the cavity to reduce the bask scatter? If it's possible you can use a radom that polarize the radiated field or resonant dipole.