Microwave oscillation circuit using a dielectric resonator

A microwave oscillation circuit comprising a dielectric resonator located on a dielectric substrate, a first high frequency transmission line formed on said dielectric substrate and having one end coupled to said dielectric resonator at a resonation frequency, and a second high frequency transmission line formed on said dielectric substrate and having one end coupled to said dielectric resonator at said resonation frequency, and a transistor mounted on said dielectric substrate and having an input terminal connected to the other end of said first high frequency transmission line and an output terminal connected to the other end of said second high frequency transmission line, so that when said transistor is driven with a DC voltage, said transistor oscillates so that an oscillation output is outputted from said output terminal of said transistor, the microwave oscillation circuit further includes a bias resistor located in the neighborhood of a connection point between said other end of said first high frequency transmission line and said input terminal of said transistor, said bias resistor having a resistance which basically determines a bias voltage supplied to said input terminal of said transistor and which is enough to make high the impedance of a bias voltage supplying circuit including said bias resistor, viewed at said input terminal of said transistor.