ACTIVE OSCILLATOR PHASE NOISE REDUCTION

IT IS PROPOSED TO REDUCE VIBRATION-INDUCED PHASE NOISE IN CRYSTAL OSCILLATORS BY A COMPACT ARRANGEMENT OF ACTIVE MOUNTINGS. SUCH MOUNTINGS ARE ENVISAGED AS PIEZOELECTRIC BENDER ELEMENTS ARRANGED SO THAT VIBRATIONS OF A BRAOD BANDWIDTH AND MODERATE AMPLITUDE ARE ABSORBED IN 1 TO 3 AXES. WHILE THE MOST CONSERVATIVE ARRANGEMENT WOULD REQUIRE AN ELECTRONIC CONTROL AND AMPLIFIER (PRESUMABLY MONOLITHIC), THE POSSIBILITY EXISTS, DUE TO THE CHARGE BEHAVIOR OF PIEZOELECTRICS, OF OPERATING WITHOUT EXTERNAL ELECTRONICS. THE GENERAL APPROACH TAKEN IN THIS PROPOSAL DOES NOT INCREASE THE COMPLEXITY OF FREQUENCY CONTROL BY THE CRYSTAL, NOR DOES IT REQUIRE COMPROMISE IN THE OSCILLATOR CRYSTAL CUT. THAT IS, IT AVOIDS POSSIBLE TECHNICAL PROBLEMS IN CRYSTAL DESIGN.