Design radar antenna at 1.5 Ghz

HI
I intend design radar antenna ( array antenna) at 1.5 Ghz. The problem here is how to choose the type of antenna. Metal dipole antenna is Ok? If i use this design I mut use with the balance line But I wonder if the feedng ( balanced line ) work in this frequency-may be the loss is big compared to that of coxial cable-. Microstrip antenna is okie, but the price may be expensive
So do any one have comercial product of 1.5 ( or suround this ) of array antenna ?
thank in advanced

Radar antennas typically are in the vicinity of 30 dBi . That implies an array or reflector.

Start by figuring out what characteristics you need and then go looking for suitable antennas.

The first:

For which radar type do you need antenna?
(air surveillance, target acquisition, ...)

Then goes everything else.

I think ND is right
first you must know the type of the radar