4681 results about "Circulator" patented technology

The present invention provides a device and method for antenna matching applied in a transceiver. Wherein, the transceiver has a transmission module and a receiving module. The antenna matching device includes a matching circuit, a duplexer, a circulator, a control unit, and a coupler. Wherein, the matching circuit adjusts the matching impedance according to an adjusting signal and generates a reflection signal. The duplexer receives the reflection signal and a receiving signal and respectively sent the received two signals to the control unit and the receiving module according to their frequencies. The control unit, according to the reflection signal, estimates the adjusting signal for adjusting the matching circuit to an optimal state of the load impedance of the matching antenna, such that the antenna gain may is maximized, and a best efficiency is obtained no matter during receiving or transmission.

A millimeter-wave transmitter-receiver uses an NRD guide as a fundamental configuration and includes a millimeter-wave signal oscillator, a pulse modulator, a circulator, an antenna and a mixer. In the millimeter-wave transmitter-receiver, a line length of a third dielectric guide is set so that δ=±π in which δ is a phase difference at a center frequency between a portion of a transmission millimeter-wave signal, which is reflected via a third dielectric guide on the leading end portion of the third dielectric guide and returned to leak to a third connecting portion of the circulator, and another portion of the millimeter-wave signal, which leaks from a first connecting portion to the third connecting portion of the circulator. It is possible to reduce the change in the mixer output and enhance the millimeter-wave transmission/reception performance.

An RFID transponder is provided with an active backscatter amplifier that amplifies and re-transmits a received signal. The RFID transponder comprises an antenna and a circulator having a first port connected to the antenna. A modulator is connected to a second port of the circulator. An amplifier is connected to a third port of the circulator, with the amplifier connected to the modulator. An RF signal impinging upon the antenna passes through the circulator, the amplifier, and the modulator, and returns to the antenna through the circulator. The modulator further comprises an input coupled to the second port of the circulator and an output coupled to an input of the amplifier. The amplifier has an output coupled to the third port of the circulator. The modulator is adapted to modulate the RF signal using on-off keying.

A transmitter/receiver combination system and a transmission signal canceling method for use in a wireless communication system using a single common antenna are provided. The system includes a circulator for receiving an original transmission signal from the transmitter, transmitting the received transmission signal to an antenna without a signal loss, and transmitting a reception signal received from the antenna to other ends without a signal loss, and a transmission signal canceller for dividing the transmission signal input in an attenuated form as much as a predetermined magnitude via the circulator together with the reception signal into two paths, producing two is phase inverted transmission signals with the same magnitude and delay time as those of the original transmission signal, and recombining the produced two transmission signals with each other, to thereby canceling the transmission signal and transmitting only the reception signal to the receiver.

An optical network for bi-directional wireless communication is disclosed. The optical network includes a remote antenna unit for converting a downlink optical signal into a downlink radio signal, transmitting the downlink radio signal wirelessly, and converting an uplink radio signal received wirelessly into an uplink optical signal. An optical line is used as a transmission medium of the downlink optical signal and the uplink optical signal. The optical network also includes a central base station including a circulator linked to the remote antenna unit through the optical line, so that the central base station outputs the downlink optical signal to the remote antenna unit through the circulator and detects the uplink optical signal inputted through the circulator.

The invention pertains to wavelength-agile optical filters suitable for wavelength-division-multiplexed (WDM) optical communications networks. More particularly, the invention pertains to optical filters with a wavelength reference that can be remotely switched to arbitrarily selectable channels on a standard grid, and to re-configurable optical communications networks employing same. The present invention provides a communication apparatus with a tunable filter which may be used in a wide range of applications including tuning an external cavity laser (ECL), selecting a wavelength for an add/drop multiplexer and providing channel selection and feedback for a wavelength locker. The filter may be utilized as a discrete component or in combination with circulators, wavelength lockers and gain medium. The filter may be implemented in whole or in part as part of a gain medium. The tunable filter exhibits a compact form factor and precise tuning to any selected wavelength of a predetermined set of wavelengths comprising a wavelength grid. The tunable filter may thus be utilized in telecom applications to generate the center wavelengths for any channel on the ITU or other optical grid.

A transmitter/receiver for use in a multichannel time division duplexing system having an independent combiner and divider to isolate a transmission channel from a reception channel. The transmitter/receiver includes a first and second circulator connected, respectively, to a first and second transceiver. A transmission channel, formed between the first and second circulators and an antenna, transfers transmission signals from the first and second transceivers to the antenna in response to a transmission enable signal. A reception channel, formed between the first and second circulators and the antenna, transfers a reception signal from the antenna to the first and second transceiver in response to a reception enable signal. A switching control circuit is provided for generating the transmission enable signal during a transmission mode of operation and for generating the reception enable signal during a reception mode of operation.

A medical treatment system, such as peritoneal dialysis system, may include control and other features to enhance patient comfort and ease of use. For example, a peritoneal dialysis system may include a control system that can adjust the volume of fluid infused into the peritoneal cavity to prevent the intraperitoneal fluid volume from exceeding a pre-determined amount. The control system can adjust by adding one or more therapy cycles, allowing for fill volumes during each cycle to be reduced. The control system may continue to allow the fluid to drain from the peritoneal cavity as completely as possible before starting the next therapy cycle. The control system may also adjust the dwell time of fluid within the peritoneal cavity during therapy cycles in order to complete a therapy within a scheduled time period. The cycler may also be configured to have a heater control system that monitors both the temperature of a heating tray and the temperature of a bag of dialysis fluid in order to bring the temperature of the dialysis fluid rapidly to a specified temperature, with minimal temperature overshoot.

A feed network for an antenna subarray includes a first feed arrangement having an sum output, a second feed arrangement having an delta output, a fixed attenuator having a first port and a second port, the first port connected to the delta output of the second feed arrangement, a first power divider/combiner having a first and second port and a third port; the first port connected to the second port of the fixed attenuator, a variable phase shifter having a first port and a second port, the first port connected to the second port of the power divider/combiner, a variable attenuator having a first port and a second port, the first port connected to the second port of the variable phase shifter, a second power divider/combiner having a first and second port and a third port; the first port connected to the second port of the fixed attenuator, a first circulator having a first port, a second port and a third port, the first port connected to the sum output of the first feed arrangement, and a third power divider/combiner having a first and second port and a third port; the third port connected to the second port of the circulator and the second port connected to the second port of the variable attenuator.

An RF front-end apparatus in a TDD wireless communication system is provided. In the RF front-end apparatus, a detector is provided at a predetermined position in a signal path, and detects a signal propagating in the signal path. A circulator provides a signal received from a power amplifier to an antenna feed line and a signal received from the antenna feed line to a switch. A switch controller generates a control signal based on the signal received from the detector and a switch on/off signal received from a control board. The switch, which is disposed at an input port of an LNA, switches on/off according to the control signal received from the switch controller.

The invention discloses a vehicle-mounted millimeter-wave radar moving target recognizer. The vehicle-mounted millimeter-wave radar moving target recognizer is characterized in that the recognizer is a frequency synthesizer; a frequency agility continuous signal is modulated into a pulse signal and then is processed into a millimeter-wave signal by up-conversion; after being amplified by a power amplifier, the millimeter-wave signal is transmitted out; an antenna receives a radar echo signal back to a circulator and then the signal is transmitted into a frequency mixer; a high-frequency echo pulse and constant-amplitude high-frequency voltage generated by a high-stability local oscillator are mixed and the signal is reduced to a middle frequency and then is processed by a middle-frequency amplifier; the middle-frequency signal is directly sampled by an A/D (Analogue/Digital) conversion module; after being sampled, echo signals of a whole pulse string are stored into a storage unit; and information of targets, such as quantity, speed and direction, is measured by a signal processing unit and then is transmitted to an alarm executing unit. With the adoption of the structure, the vehicle-mounted millimeter-wave radar moving target recognizer has the advantages that 1 the distance measuring precision and the angle measuring precision of a moving target are improved; and 2 excessive hardware does not need to be added and the production cost is lower.

A resonator system comprises an optical resonator that supports one or more pairs of nearly degenerate defect states. One or more magnetic domains comprising at least one gyrotropic material in the optical resonator cause magneto-optical coupling between the two states so that the system lacks time-reversal symmetry. In one embodiment, a single magnetic domain is used that dominates induced magneto-optical coupling between the defect states. The above resonator system may be used together with other components such as waveguides to form circulators, add drop filters, switches and memories.

The invention relates to the technical field of radio fix radars, in particular to a millimetre wave time-division linear frequency modulation multi-object detection automobile anti-collision radar. The radar of the invention adopts full phase parameter receiving/emitting benchmark signal and time-division and time-sequence asynchronous control to receive/emit a dual-purpose quasi-light integrated medium lens antenna array, and scans the objects possible to be collided on the warning road surfaces by DSP according to lane scanning wave beam; the road situation photographing combined with the vehicle speed and GPS data MCU to control time-division n-passage modulation frequency and waveform millimetre wave linear locking phase frequency modulation; emission is carried out sequentially by R/T2, a circulator, a wave beam switch and the antenna array; echo passes through the antenna array, the wave beam switch, the circulator, the R/T1, low noise high amplifier, subharmonic mixing, middle amplifier and a time-dividing circuit and multi-object signal corresponding matching filter wave and is processed and controlled by MCU at DSP; when a plurality of road barriers are encountered, the orientation, distance and relative speed are determined by DSP restriction virtual warning; three-dimensional images are displayed by a CRT; the closer the distance of the object is, the higher the resolution is; the object which is closest to the vehicle is recognised; sound and light alarm are carried out when the distance is less than safety distance; when the distance is near to the dangerous distance, the vehicle can intelligently avoid the barrier or reduce the speed or brake; the radar of the invention can make a choice according to the control reference road situation, the vehicle speed and the GPS data, thus obviously improving the driving safety of the vehicle.

A sous vide cooking appliance which holds the cooking liquid and vacuum packed food, circulates the liquid, heats the liquid, and regulates the temperature of the liquid.

A transmitting apparatus in a TDD wireless communication system is provided. In the transmitting apparatus, a circulator transmits a signal received from a power amplifier to an antenna feed line and transmits a signal received from the antenna feed line to a quarter-wave transmission line. The quarter-wave transmission line is installed in a reception path, for reception isolation in a transmission mode. An RF switch shorts the load of the quarter-wave transmission line to the ground or connects the load of the quarter-wave transmission line to an LNA according to a control signal. The LNA low-noise-amplifies a signal received from the RF switch.

Fiber-optic-based systems and methods for monitoring physical parameters using a remotely deployed circulator are disclosed. In a preferred embodiment the circulator is remotely deployed with respect to an optical source/detector and coupled thereto by two dedicated fiber optical cables: a forward line for passing light from the source through the circulator to fiber-optic-based sensors, and a return line for passing light reflected from the sensors through the circulator back to the detector. By using separate forward and return lines in conjunction with the circulator, backscattering phenomenon experienced on the forward line will not interfere with the reflected light signals coming from the sensors. The circulator, and hence the sensors, may therefore be remotely deployed from the source/detector present at a monitoring station, greatly expanding distances which optical sensing systems can span.