Dielectric resonant oscillator.

摘要

A dielectric resonant ocillator for use in frequency conversion of X-band signals comprises a dielectric 'puck' (1) of high dielectric constant mounted on a printed circuit board (3) adjacent a stripline conductor (5). The puck (1) forms a resonant cavity to signals in the stripline and the system oscillates typically at X-band. The puck (1) has an inherent temperature compensating dielectric/temperature characteristic which generally compensates temperature dependent circuit characteristics. However the substrate (3) dielectric/temperature characteristic (Figure 1) upsets the balance, the substrate (3) being coupled to the cavity by the electric field. The balance is regained by introducing a metallic pad (7) under the puck of (1) half the puck diameter thus bringing the temperature driven variation to 1.25 ppm. A further development provides 2 or more radial extensions (9) of the pad (7) which shift unwanted hybrid modes away from the wanted TEM mode and prevent mode jumping and consequent instability.