252 results about "Microwave amplifiers" patented technology

A materials processing system comprises a thermal processing chamber and a broadband microwave power source. The power source includes an ovenized small-signal RF circuit, a high power microwave amplifier, and forward and reflected power detectors separated from one another by an isolator. The power detectors are also preferably ovenized. A control system provides control signals to the thermally stabilized VCO and VCA in the small-signal circuit to control output power based on detected forward power compared to demanded forward power. The system may be run in either open-loop or closed-loop modes.

The invention discloses an online long-pulse high-power directional coupler performance testing device and method. The online long-pulse high-power directional coupler performance testing device comprises a high-power klystron system and a vector network analyzer, the output end of the vector network analyzer is connected with a micro-wave amplifier through a micro-wave switch, the output end of the micro-wave amplifier is connect with the high-power klystron system through a first direct current break device, the output end of the high-power klystron system is connected with a bi-directional coupler through a circulator, coupling output signals of the bi-directional coupler are accessed into the vector network analyzer through a micro-wave cable after passing an attenuator and the direct current break device, and the wave guide output of the bi-directional coupler is connected to a high-power water load. The online long-pulse high-power directional coupler performance testing device uses the network analyzer as a testing apparatus and uses the output signals (about 10 mW) of the network analyzer as an oscillation source of the klystron, through testing under different klystron output power and recording S21 parameters obtained by the vector network analyzer under a long-pulse (more than 1000 s) stable running condition, the global performance of the directional coupler is obtained.

Provided is a microwave-signal generating method and device based on the excited brillouin scattering effect and the optical frequency comb in high nonlinear fibers. The invention belongs to the technical field of microwave photonics. The device comprises a tunable laser, a first coupler, a second coupler, a first circulator, a second circulator, a first high nonlinear fiber, an attenuator, a fourth coupler, a first photoelectric detector, a power divider, an intensity modulator, a fourth DC voltage regulator, a first double parallel mach-zehnder modulator, a fifth DC voltage regulator, a sixth DC voltage regulator, a seventh DC voltage regulator, a third circulator, a second high nonlinear fiber, a third coupler, a second photoelectric detector, a microwave amplifier, a second double parallel mach-zehnder modulator, a first DC voltage regulator, a second DC voltage regulator, a third DC voltage regulator, an isolator, a fifth coupler, a third photoelectric detector and a frequency analyzer. Due to the advantages of mode selection and positive feedback of a photoelectric oscillator, the microwave signals which are output by the device have the advantages of good spectrum purity and low noises.

The invention discloses an optoelectronic oscillation loop-based microwave two-third frequency division method, which comprises the following steps: performing primary carrier suppression optical double-sideband modulation on a photocarrier by use of a microwave signal to be subjected to frequency division, then performing secondary carrier suppression optical double-sideband modulation on a primarily modulated optical signal by use of an oscillation signal, converting a secondarily modulated optical signal into an electrical signal by use of a photodetector, causing the electrical signal to pass through a microwave amplifier, a phase shifter and a microwave filter, dividing the electrical signal into two paths as an oscillation signal and two-third frequency division output respectively,and forming positive feedback oscillation in a two-third frequency division oscillation mode in an optoelectronic oscillation loop, thereby obtaining stable two-third frequency division output. The invention also discloses an optoelectronic oscillation loop-based microwave two-third frequency division device. According to the method and the device, two-third frequency division of any microwave signal can be implemented in an optical domain, and the advantages of great bandwidth, low noise, low spur and little interference to the outside are achieved.

The invention provides an angular speed measuring method and device based on a photoelectric oscillator. The device comprises a light source, a first polarization controller, an electrooptical modulator, an Sagnac interferometer, a photoelectric detector, a band filter, a microwave amplifier and a power divider, wherein the Sagnac interferometer comprises an optical circulator, a second polarization controller, a light beam splitter, a Sagnac ring, a rotating table and a polarizer. The method comprises the steps: measuring the frequency fosc of an oscillator signal output by the powder divider when the Sagnac ring is static, measuring the frequency f'osc of an oscillator signal output by the powder divider when the Sagnac ring rotates at the angular speed omega, and calculating the angular speed omega based on the fosc, the f'osc and the parameters of the loop circuit of the photoelectric oscillator. According to the angular speed measuring method and device based on the photoelectric oscillator, the Sagnac ring is embedded into the photoelectric oscillator, the phase change of the Sagnac ring resulted from the angular speed omega is mapped to the oscillation frequency change of the photoelectric oscillator, and simultaneously, the advantages of high-quality microwave signals produced by the photoelectric oscillator and high-resolution microwave measurement are combined, thereby greatly improving the sensitivity and resolution in measuring the angular speed omega.