This thesis presents the designs of 2.4GHz and 5.2GHz voltage control oscillators by two kinds of microwave resonator. he 2.4GHz VCO uses microstrip line resonator and the 5.2GHz VCO uses substrate integrated waveguide (SIW) cavity resonator. Low pass filters are added at output port of each VCO to improve its harmonic rejection. The simulated results for both VCOs are presented and their performances are compared with other VCOs.
