VCO at 13 GHz?

I want to design VCO at 13 GHz with BJT infineon BFP520 in microstrip technology(rogers). At the moment i'm stucked at 7 GHz.....is there any examples of similar design? Does anyone has some suggestions what i should do?

send me 7 ghz oscillator. so that i can help you. these my email.ramaraju.bari@gmail.com.i am also working on the vco by usind ads

Added after 3 minutes:

ramaraju.bandari@gmail.com