A tunable distributed voltage controlled oscillator for generating high frequency microwave signals. The oscillator comprises a plurality of stages of complimentary metal oxide semiconductor (CMOS) inverters in parallel configuration. Each of the inverters comprises a p-metal oxide semiconductor field effect transistor (MOSFET) at the top and a n-metal oxide semiconductor field effect transistor (MOSFET) at the bottom with their gates connected to a supply voltage and to a gate transmission line and their drains connected to the supply voltage and to a drain transmission line . The drain transmission line and the gate transmission line are connected to each other through a feed back path . The drain transmission line and the gate transmission line each comprises a plurality of coplanar wave guides in series respectively. The number of coplanar wave guide in each of the gate and drain transmission lines is greater than the number of stages of CMOS inverters by a factor of 1. The body of the p-MOSFET is inwardly directed and connected to a forward body bias voltage and the source of the p-MOSFET is connected to the supply voltage. The body of the n-MOSFET is outwardly directed and the body and source of the n-MOSFET are earthed. The gate transmission line further comprises a frequency collector .