Abstract:
A tuned oscillator is disclosed which comprises an active element (37), a resonator (35) electrically connected to the active element and made of a magnetic material using ferromagnetic resonance phenomenon, and a magnetic circuit for applying a magnetic field to the resonator. The resonator is made of an YIG (yttrium, iron and garnet) thin film magnetic resonance element formed by a thin film forming technique and utilizes an uniform mode ferro-magnetic resonance in the YIG thin film, and operating under the application of magnetic field of the magnetic circuit.
Abstract:
A swept synthesizer signal source provides a digital synchronization signal for accurate internal synchronization of events and for external synchronization of data taking and other operations to predetermined frequencies generated by an oscillator during a sweep. The digital synchronization signal includes a predetermined number of digital pulses, regardless of the sweep time. A ramp voltage which controls the oscillator is corrected during a calibration period to sweep between predetermined limits, thereby insuring that the ramp voltage is synchronized to the digital synchronization signal. The slope of the frequency versus time sweep is also corrected to further improve accuracy. A power level correction technique insures precision power leveling regardless of the sweep range. A table of correction/frequency pairs is entered into the instrument, and an interpolation algorithm is employed to determine corrections at frequencies corresponding to each synchronization pulse. The source can be used in a network analyzer system wherein the synchronization pulses are provided to a receiver to trigger data taking. Two or more sources can be interconnected to provide synchronized sweeps.
Abstract:
A microwave synthesiser comprising: a plurality of oscillator sources (1, 13, 3, 15, 5, 17, 7), each for generating signals over a range of frequencies, said ranges of frequencies together extending over a total range of frequencies generated; means (19, 31, 83, 37, 38, 41, 81) for phase-locking any selected one of said oscillator sources (1, 13, 3, 15, 5, 17, 7) so that it generates signals of a frequency at which it is set; a single low harmonic modulator (21) for modulating the signals generated by the selected one of said oscillator sources (1, 13, 3, 15, 5, 17, 7), the modulated signals passing to an output (27) of said synthesiser; and at said output (27) means (25, 29) for detecting the power of the signals at said output (27), the modulation by said single low harmonic modulator (21) being controlled in dependence on the detected power thereby to control the power of the signals at said output (27).
Abstract:
An oscillator (10) providing predictable oscillator modulation sensitivity includes an amplifier (11) and a feedback circuit (29) disposed about the amplifier (11). The feedback circuit (11) includes a resonator (13) having a first port and a second port, and a voltage-controlled phase shifter (27) having an input port, an output port and a control port (27a), the input port of the voltage-controlled phase shifter (27) being connected to the output port of the amplifier (11) and the output port of the voltage-controlled phase shifter (27) being coupled to a port of the resonator (13). The oscillator (10) further includes a circuit (30), responsive to signals from the output of the voltage-controlled phase shifter (27) and the first port of the resonator (13), to provide a control signal (25a) to the control port (27a) of the voltage-controlled phase shifter (27) for degenerating low frequency FM noise arising within the amplifier (10).
Abstract:
A swept synthesizer signal source provides a digital synchronization signal for accurate internal synchronization of events and for external synchronization of data taking and other operations to predetermined frequencies generated by an oscillator during a sweep. The digital synchronization signal includes a predetermined number of digital pulses, regardless of the sweep time. A ramp voltage which controls the oscillator is corrected during a calibration period to sweep between predetermined limits, thereby insuring that the ramp voltage is synchronized to the digital synchronization signal. The slope of the frequency versus time sweep is also corrected to further improve accuracy. A power level correction technique insures precision power leveling regardless of the sweep range. A table of correction/frequency pairs is entered into the instrument, and an interpolation algorithm is employed to determine corrections at frequencies corresponding to each synchronization pulse. The source can be used in a network analyzer system wherein the synchronization pulses are provided to a receiver to trigger data taking. Two or more sources can be interconnected to provide synchronized sweeps.
Abstract:
L'invention concerne un oscillateur à très hautes fréquences (4-22 GHz) comportant deux résonateurs à billes de Yig. L'oscillateur selon l'invention, basé sur un transistor à effet de champ (1), comporte deux billes de YIG (21, 22) dont les fréquences de résonance sont décalées (àF) ce qui lui communique une large bande de fréquences. En outre, l'une des deux billes (21) est doublement couplée (en 23 et 24) à la source et à la grille du transistor (1), ce qui communique à l'oscillateur une bonne linéarité (≃10 -3 ) dans la bande de fréquence. L'oscillateur est caractérisé en ce qu'une bille de YIG (21) est doublement couplée (en 23 et 24) au transistor (1), et en ce que l'un des deux fils de couplage, celui qui est connecté à la grille du transistor (1), est doublement couplé (en 24) à la première bille (21) et (en 25) à la seconde bille (22). Application aux matériels hyperfréquences.
Abstract:
A tuned oscillator is disclosed which comprises an active element (37), a resonator (35) electrically connected to the active element and made of a magnetic material using ferromagnetic resonance phenomenon, and a magnetic circuit for applying a magnetic field to the resonator. The resonator is made of an YIG (yttrium, iron and garnet) thin film magnetic resonance element formed by a thin film forming technique and utilizes an uniform mode ferro-magnetic resonance in the YIG thin film, and operating under the application of magnetic field of the magnetic circuit.