stacked patch antenna gain

[jiyaa]

hi all,
can any one plz help me that how can i increase the gain of a stacked patch antenna, as with stacked patch greater BW can be achieved but gain reduces. any parameters that can be used to control the gain.

thanks

 

[thylacine1975]

What substrate are you using? I found that the dielectric losses of my stacked patches hammered the gain. The difference between a typical FR-4-type loss tangent of 0.02 and a better substrate at 0.002 yeilded more than a dB improvement for me at 2.4 GHz.