I would keep the same antenna, add a MMIC amplifier followed by a stripline bandpass filter, since they are lower loss than LC BPF.
Hope this helps.
Victor
Hi.
From my experience, ground vias should be placed about every 1/10 lambda. Also, at frequencies aproaching 1GHz, the traces should be impedance matched to 50Ohms, or whatever system impedance you are using. AppCAD works well for this. You can download it, or request a CD from Agilent...