dielectric resonator oscillator smith chart

Reflection type oscillators which couple a dielectric resonator to the output circuit one half wavelength away from the transistor (such as a field effect transistor), exhibit significantly improved FM noise performance and frequency stability over that of a conventional oscillator. They are therefore the logical choice for many fixed frequency receiver/transmitter low noise oscillator applications.ĭielectric resonator oscillators can generally be classified as being either reflection or feedback type oscillators. Their use maximizes the performance to size ratio for many filters and oscillators, thus enabling low cost and manufacturing components to be realized. These high permittivity materials are available from several manufacturers with a variety of dielectric constants and temperature coefficients. In the past, a variety of microwave components which employ dielectric resonators have been developed due to the availability of low cost temperature stable, high permittivity materials. This invention relates to push-push oscillator circuits for operation in the range of 20 to 40 GHZ and more particular to push-push dielectric resonator oscillators.

The push-push dielectric resonator oscillator circuit according to claim 1 wherein the combining means comprises: a first and second transmission line having a length equal to a half wavelength of the first frequency joined together at one end with the opposite ends connected to the drains of the field effect transistors of the first oscillator means and the second oscillator means, and a third transmission line connected to the joint of the first and second transmission line at one end with said output being provided at the other end. The push-push dielectric resonator oscillator circuit according to claim 2, wherein the dielectric resonator further ensures antiphaseal relationship between the first oscillator means and the second oscillator means.Ĥ. The push-push dielectric resonator circuit according to claim 1, wherein the resonating circuit comprises:Ī first transmission line having a first length and connected to the gate of the first transistor on one end and to the first termination circuit on the other end Ī second transmission line having the first length and connected to the gate of the second transistor on one end and to the second termination circuit on the other end, the second transmission line being located in a predetermined positional relationship to the first transmission line andĪ dielectric resonator means for connecting magnetic energy between the first transmission line and the second transmission line.ģ. The first and second oscillator means each include a field effect transistor circuit including a field effect transistor having a gate, a drain and a source, a resonating circuit tuned to resonate at the first frequency as its fundamental frequency connected to the gate of the field effect transistor, a network circuit tuned for impedance matching at the first frequency and connected to the source, and an output circuit tuned for impedance matching at the first frequency and connected to the drain.Ģ. A push-push dielectric resonator oscillator circuit, comprising:Ī first oscillator means for generating a first signal at a first frequency and phase Ī second oscillator means for generating a second signal at the first frequency and at a second phase Ī resonator means for maintaining an antiphase relationship between the first signal and the second signal Ĭombining means for vectorially combining the first and second signals to obtain an output signal at a second frequency and

Dielectric resonator oscillator smith chart