coaxial vco design

how about the frequency?

not enough information.. for the design

Frequency about 950MHz, tuning range 30MHz.

Problem with microstrip resonators is that the overall Q is not very high, for the same space you could use a coaxial resonator and achieve lower phase noise. Whilst the high Q resonator will give you lower phase noise you really have to consider the matching from the resonator to the active device. ie resonator to the base of the transistor.