36 results about "Tuned filter" patented technology

The application discloses a kind of single crystal resonator ferromagnetic resonance line width fast screening device for magnetic tuning filter, belong to microwave component testing field, the testing device includes resonator (1), resonator (2), adjustable DC power supply (3) and vector network analyzer (4);Wherein, the resonator (2) after orientation is placed in resonator (1), the resonator (1) is connected with vector network analyzer (4) and adjustable DC power supply (3) respectively by data line, the application also discloses the method for using the above device to carry out single crystal resonator ferromagnetic resonance line width fast screening for magnetic tuning filter;The screening device of the application can realize the screening of one sample in 30 seconds, and the testing accuracy is good, can meet the demand of batch product screening test, is favorable for improving the tuning efficiency of magnetic tuning filter, reduces production cost, has very strong practical value.

A radio frequency (RF) monitoring apparatus (102), comprising: an RF forward input port (116) and corresponding reverse input port (118); a tunable filter (218); an RF detector (220); an electronic processor (202) comprising a tuning signal output (208), wherein the processor (202) is configured to selectively generate a tuning signal at the tuning signal output corresponding with one or more specified frequency sub-bands, to record RF power signals generated by the RF detector (220) corresponding with RF signals received at the forward and reverse input ports (116, 118) within the specified frequency sub-bands, and to provide monitoring signals determined from the recorded RF power signals.

This invention relates to the fields of optical fiber communication and microwave photonics. Existing tunable dual-passband microwave photonic filters suffer from poor passband stability and cannot meet practical application requirements. This invention provides a narrow-band tunable dual-passband microwave photonic filter using a Brillouin fiber laser. It generates dual-tone pump light to excite the Brillouin using a tunable laser source and an intensity modulator. Combined with a Brillouin fiber oscillator and a cascaded Fabry-Perot cavity, the Brillouin gain spectrum is narrowed to the kHz level. Simultaneously, the different periodic resonant frequencies of the two ring cavities effectively suppress side modes, filtering out the desired frequency band signal. Furthermore, by synchronously tuning the center frequencies of the two passbands of the filter by changing the pump light wavelength, and simultaneously controlling the output frequency of the signal generator, the frequency interval between the two passbands is changed, ultimately realizing a narrow-linewidth tunable dual-passband microwave photonic filter.

The invention discloses a low-loss high-tunability BZT laminated dielectric film and a preparation method thereof, the laminated film comprises a substrate, a BZT film layer and a zinc niobate-based microwave dielectric ceramic film layer, and the chemical general formula of the zinc niobate film layer is Zn [(Ge0. 5Mo0. 5) xNb1-x] 2O6. A ceramic target material is synthesized by adopting a solid-phase reaction method, and thin film layers are sequentially deposited through a magnetron sputtering technology to construct a heterostructure. The high dielectric constant of BZT and the low loss characteristic of zinc niobate are combined, the frequency characteristic is remarkably improved, the dielectric loss is effectively reduced while the high tunability is kept, and the high-quality FOM is obtained and reaches 36.77. The film is excellent in performance and controllable in process, and has important application value in microwave communication devices such as tunable filters and phased array radars.

The present subject matter provides a method and apparatus for tuning an ANC based on a user hearing threshold level, in which hearing threshold level data of a user is obtained by performing a hearing test on the user, and an ANC filter is tuned based on the hearing threshold level data of the user, thereby enabling the user to obtain a more optimized ANC effect.

The invention discloses a system and method for detecting the junction temperature of LD chips in batches in real time, the system comprises aging and testing equipment, an MEMS optical switch, an acousto-optic tunable filter and a PD, the aging and testing equipment comprises a plurality of aging testing modules, the system further comprises a real-time operation, processing and control unit RTOPCU, and the real-time operation, processing and control unit RTOPCU is connected with the MEMS optical switch, the acousto-optic tunable filter and the PD. The control module is also used for controlling the COS unit of each aging test module to output laser, controlling the switching from the multi-path optical fiber input of the MEMS optical switch to the single-path optical fiber output of the MEMS optical switch, and controlling the input voltage of the acousto-optic tunable filter; filtering the multi-wavelength laser output of the MEMS optical switch to obtain a single-wavelength laser output signal corresponding to the input voltage of the MEMS optical switch; synchronously receiving a PD output voltage value obtained by detecting, amplifying and converting the laser signal output by the tunable filter converted by the PD; and calculating the junction temperature of the current COS unit under the condition that the PD output voltage value is not less than the threshold voltage value.

The application discloses a parameter design method of a double-tuned filter with damping, and belongs to the technical field of power quality treatment, comprising the following steps: determining the design reactance range of the double-tuned filter under each frequency band according to the harmonic range required to be filtered out by a target power grid area; selecting the optimal parameters of the inductance and the capacitance of the double-tuned filter with the lowest cost as the target; selecting the optimal damping parameters based on the optimization requirements of the load and the energy loss, and determining the final parameter design scheme. The parameter design method of the double-tuned filter with damping can reduce the energy loss as much as possible under the condition of guaranteeing a low harmonic level and a low component cost, realize the parameter design of the double-tuned filter, and has the advantages of low cost, low loss, convenient calculation, high practicability and high reliability.

A self-tuning, resonant cavity transmitter combiner joins multiple RF transmitters and combines their signals onto a single transmission line. An additional tuning element is added to the junction of the signal paths to overcome the bandwidth limitations of the transmission lines joining the signal paths. An algorithm was developed to optimize the RF performance of the combiner by sampling the RF signals at various points in the RF circuit.

A tunable optical filter with a top-hat pass band shape. The proposed tunable optical filter is adapted to be installed over a top surface of a sensor, and comprises a set of at least three stacked dielectric mirrors parallelly adjacent to the plane of installation of the sensor, the at least three stacked dielectric mirrors comprise an upper mirror, an intermediate mirror and a lower mirror, wherein the set of at least three stacked mirrors is spaced within a variable distance to create at least two independent and adjacently equal volumetry cavities between the upper mirror and the intermediate mirror and between the intermediate mirror and the lower mirror.

The invention discloses a reliable direct-type identification method for characteristic parameters of a single-tuned filter, which comprises the following steps of: initializing the single-tuned filter to be detected to be in a zero state, applying a direct-current excitation source with constant amplitude to the single-tuned filter to be detected, sampling, storing a current sequence of the single-tuned filter, carrying out sliding mean filtering processing on a sample, and carrying out direct-current identification on the characteristic parameters of the single-tuned filter. Calculating an identification element, calculating an identification basic parameter, calculating an identification characteristic quantity, and obtaining the characteristic parameters of the single-tuned filter, such as resistance R, inductance L and capacitance C; according to the method, the single-tuned filter is used as a detection object, the characteristic parameters of the single-tuned filter are monitored in real time, a simulation model of the single-tuned filter is constructed, the identification method of the characteristic parameters in the filter is verified through experiments, and the identification method is confirmed to be accurate and reliable on the premise that the filter device is not disassembled and not damaged through analysis of experimental results. And the characteristic parameters of the single-tuned filter in the interference environment can be accurately and reliably estimated.

The invention discloses a superconductive multi-path coupler based on an impedance traction network. Comprising a common end, a first tunable filter circuit, a second tunable filter circuit and a plurality of impedance traction networks, and the first tunable filter circuit comprises a first branch knot and a plurality of first tunable filters arranged on the first branch knot; the second tunable filter circuit comprises a second branch knot and a plurality of second tunable filters arranged on the second branch knot; and at least one of the signal input end and the signal output end of each first tunable filter and each second tunable filter is provided with an impedance traction network for adjusting the port reactance of the first tunable filter and the second tunable filter. The impedance traction network is arranged at the signal input end and / or the signal output end of the first tunable filter and the second tunable filter, and the port reactance of the first tunable filter and the second tunable filter can be adjusted on line, so that the passband return loss performance of the multi-path coupler is improved.

The invention relates to an acousto-optic tunable filter (Acoustical-optical tunable filter-AOTF), which is an electrically controlled tunable spectrum light splitting device, and is characterized in that the acousto-optic tunable filter (Acoustical-optical tunable filter-AOTF) is an electrically controlled tunable spectrum light splitting device. In a complex task, single-band information is often insufficient to support a decision, so that the invention provides a design method of a single transducer-dual-band acousto-optic tunable filter, a numerical calculation model is established through a dual-band wave vector geometry principle, and a dual-band tuning relationship under different cutting types is obtained. And furthermore, the design of the dual-band AOTF device with high diffraction efficiency and low power consumption is realized through the size optimization design of the transducer. Compared with an existing AOTF device design method, the single-transducer-dual-waveband AOTF device design method can utilize a single simple single-transducer AOTF device to obtain dual-waveband spectral data at the same time, the spectral range is expanded, the spectral detection efficiency is improved, and the detection capacity for a dynamic target is improved. Meanwhile, the dual-band detection can reduce the frequency of electrical power loading of the transducer, the thermal load of the device is reduced, and the working stability of the device is improved.

The invention provides an acousto-optic tunable filter device and an optical processing mechanism. The acousto-optic tunable filter device comprises an acousto-optic acting medium; the radio frequency array comprises a plurality of radio frequency assemblies and is arranged on the first side of the acousto-optic interaction medium, the radio frequency assemblies are suitable for emitting radio frequency signals in a working state, and the radio frequency signals excite sound wave signals in the acousto-optic interaction medium to form an acoustic grating; wherein the number of the radio frequency components in the radio frequency array is changed to change the effective action length of the acoustic grating in the acousto-optic action medium, so that the spectral resolution of the acousto-optic tunable filter is adjusted.

The application discloses a specified harmonic compensation method of a hybrid active filter, which simulates a virtual capacitor for a voltage source inverter in a harmonic domain, and the capacitor value can be adaptively adjusted by a perturbation and observation method, so that the LC filter and the virtual capacitor can generate series resonance at a specified harmonic frequency, and the effect of a multi-tuned filter is achieved, thereby greatly improving the filtering characteristic of the LC single-tuned filter; the control method has the advantages of simple control structure, easy implementation and good filtering effect.

The application belongs to the field of femtosecond laser technology, and particularly relates to a few-cycle high-energy fiber chirped pulse amplification system and method. The system comprises a seed source module, a chirped pulse amplification module and a hybrid compression module. The seed source module adopts a nonlinear polarization rotation mode-locked resonator with an integrated tunable filter to generate linear chirped wide spectrum seed pulses with tunable central wavelength. The chirped pulse amplification module realizes energy amplification while effectively suppressing gain narrowing effect through a three-stage structure of pre-chirp management, pre-amplification and main amplification. The hybrid compression module adopts a cascaded scheme of a diffraction grating compressor and a fiber soliton self-compressor to finally compress the pulse width to two optical periods. The application solves the problem that high energy and few cycles are difficult to be considered in a C-band fiber amplification system, and can output high peak power pulses of hundreds of nanojoules and two optical periods.

The invention relates to the technical field of liquid crystal materials, and particularly discloses an isothiocyanate liquid crystal compound, a liquid crystal composition containing the isothiocyanate liquid crystal compound and a high-frequency assembly. The liquid crystal compound is a compound as shown in the following formula I, and Q1 represents O, S or Se. The main ring of the molecular structure of the liquid crystal compound provided by the invention contains a benzofuran, benzothiophene or benzoselenophene structure, and the liquid crystal compound with the specific structure has the advantages of higher clearing point, lower dielectric loss, higher dielectric tuning rate tau and higher quality factor eta. The liquid crystal composition containing the organic compound also has a higher clearing point, lower dielectric loss, higher dielectric tuning rate tau and a higher quality factor eta, and can be used for developing components and devices which are applied in a microwave range and have a high-frequency technology; the invention particularly relates to a microwave phase shifter, a tunable filter, a tunable metamaterial structure and an electronic beam control antenna. I.

The present invention provides an optical receiving device and an optical receiving module having a tunable wavelength filter. [Solution] The optical receiving device includes a thermoelectric element 320 arranged on a substrate 310, a first tunable wavelength filter 330 with one end positioned on one side of the thermoelectric element and the other end positioned lower and inclined than the plane of the thermoelectric element, which transmits only a first wavelength that varies according to the temperature of the thermoelectric element, a second tunable wavelength filter 350 positioned above the first tunable wavelength filter and spaced apart on one side of the thermoelectric element, which transmits only a second wavelength that varies according to the temperature of the thermoelectric element, a first detector 360 positioned on the substrate at a distance from the thermoelectric element and on the optical axis of the received signal, which detects signals that pass through both the first tunable wavelength filter and the second tunable wavelength filter, and a second detector 370 positioned at a distance from the first detector on the substrate and which detects signals that have passed through the second tunable wavelength filter and are reflected by the first tunable wavelength filter.

A tunable filter (40; 50; 60; 70; 80; 80'; 90; 130) with tunable suppression, comprising: a first inductor (L1); a second inductor (L2) mutually coupled to the first inductor (L1), wherein the first inductor (L1) is connected in series with the second inductor (L2); and a tunable capacitor circuit (42; 52; 62; 72; 74; 92) which is electrically connected in parallel to the first inductor (L1) which has a switch (S11, S12, ..., S1N; S21, S22, ..., S2N; S31, S32, ..., S3N; S41, S42, ..., S4N; S51, S52, ..., S5N) and which is designed to match at least two notches in the frequency response of the tunable filter by changing a switching state of the switch (S11, S12, ..., S1N; S21, S22, ..., S2N; S31, S32, ..., S3N; S41, S42, ..., S4N; S51, S52, ..., S5N), wherein the tunable filter is designed to filter a high-frequency signal.

An electronic device may include aggressor circuitry that produces noise at a victim frequency, which can adversely affect the operation of victim circuitry. Tunable filter circuitry may be coupled to the aggressor circuitry and / or the victim circuitry. Control circuitry may control the filter state of the tunable filter circuitry based on victim circuitry state and / or aggressor circuitry state to remove the noise at the victim frequency.

This invention discloses a polarization-insensitive five-channel, six-wavelength selective switch with dynamic gain compensation, relating to the field of optical communication technology. It includes an input module, a polarization processing module, a beam splitting module, a dynamic gain compensation module, a wavelength selection module, a beam combining detector, and a redundancy fault-tolerant unit connected sequentially via optical paths. By integrating the dynamic gain compensation module and combining it with distributed temperature and PMD monitoring, the attenuation coefficient is dynamically updated and polarization-related gain deviations are accurately compensated. This solves the problems of large size and high cost of traditional solutions, eliminating polarization sensitivity at the source and significantly reducing polarization-related losses. The wavelength selection module uses a matrix-type tunable filter to achieve independent scheduling of five channels and six wavelengths, improving the utilization rate of optical network resources, reducing multi-channel beam splitting loss deviations, reducing output signal power fluctuations, lowering the receiver bit error rate, and enabling dynamic gain adjustment based on real-time attenuation of different wavelengths and channels, resulting in high adaptability.

The invention discloses a method for designing a piezoelectric ceramic tuned filter considering hysteresis effect compensation, and the method comprises the steps: 1, setting specific constraint conditions, such as frequency range, insertion loss and the like, based on the actual frequency conversion EMI inhibition demands, therefore, the filter can effectively work in the frequency conversion noise suppression process; 2, response data of the piezoelectric ceramic filter are sampled in real time, the bias voltage is dynamically adjusted based on the hysteresis compensation factor, it is ensured that the filter can keep high frequency adjustment precision through the dynamic adjustment, and therefore frequency conversion noise is restrained, and a filtering result meeting the constraint condition is obtained. The piezoelectric ceramic tuned filter can effectively compensate frequency deviation caused by a piezoelectric ceramic hysteresis effect, and the adjustment precision and the noise suppression performance of the piezoelectric ceramic tuned filter are improved.

The application discloses a middle infrared narrow-band tunable filter based on a phase change material GST and particularly relates to the technical field of micro-nano optical devices, and the filter comprises a dielectric substrate layer and a double-rectangular superstructure grating layer arranged periodically on the dielectric substrate layer; the double-rectangular superstructure grating layer comprises first rectangular microstructures and second rectangular microstructures arranged with a certain interval; the first rectangular microstructures are Ge cuboid blocks; and the second rectangular microstructures are composed of Ge cuboid blocks similar to the first rectangular microstructures and phase change material GST blocks with variable dielectric constants embedded at the bottom of the second rectangular microstructures. The tunability of the center wavelength position and the bandwidth of the filter is realized by the change of the incident light inclination angle and the different phase states of the GST, the demand of dynamic regulation of the transmission spectrum is met, and the utilization rate of the filter is greatly improved, so that the filter has the flexible tuning characteristics in practice.

The invention discloses a topological structure of an offshore wind power intermediate-frequency collection system, which is characterized in that an intermediate-frequency network-following type wind turbine generator and an intermediate-frequency network-constructing type wind turbine generator are connected in parallel and collected and then are connected with an uncontrolled rectifying circuit through a tuned filter to form the offshore wind power intermediate-frequency collection system; according to the control strategy of a network-forming type network-side converter adopted in the intermediate-frequency network-forming type wind turbine generator set, reference frequency and reference phase are generated through Q-f control based on a phase-locked loop, damping and inertia; in the process of Q-f control and generation of a given angular velocity, information of a primary side of a double-winding transformer of the intermediate-frequency net-forming type wind turbine generator is collected through a phase-locked loop, damping and inertia links are added in the process of Q-f control and generation of a reference angular velocity, and a reference d-axis voltage is generated through P-V droop control. And the network-forming type grid-side converter is controlled through voltage and current double-closed-loop control. According to the invention, circulation generated when the wind speed fluctuates greatly during the operation of the intermediate-frequency collection system can be reduced.

The utility model discloses a circuit structure of a 108MHz-678MHz high-suppression large-bandwidth electrically tunable filter, which belongs to the technical field of electrically tunable filters and comprises a circuit structure of a 108MHz-225MHz tuned filter, a circuit structure of a 225MHz-400MHz tuned filter, a circuit structure of a 108MHz-225MHz tuned filter and a circuit structure of a 108MHz-678MHz straight-through path. One end of each of the circuit structures of the 108MHz-225MHz tuned filter, the 225MHz-400MHz tuned filter and the 108MHz-225MHz tuned filter and the circuit structure of the 108MHz-678MHz straight-through path is connected with the radio frequency switch U1, the other end of each of the circuit structures of the 108MHz-225MHz tuned filter and the circuit structure of the 108MHz-678MHz straight-through path is connected with the three low-pass filters and the radio frequency switch U2, and the other ends of the three low-pass filters are connected with the radio frequency switch U2. The main magnet ring inductor of the electrically tunable filter is a hollow coil wound by an enameled wire. According to the utility model, the size of the electrically tunable filter is reduced by reducing the number of inductors; through the testing tool, the pins are prevented from being damaged, and the testing efficiency and accuracy are improved.

The application discloses a kind of short tube carbon nanotube nanometer membrane-based hybrid waveguide filter and preparation method thereof, comprising: single-mode optical fiber, straight waveguide, micro-ring waveguide and short tube carbon nanotube nanometer film;Single-mode optical fiber includes a fiber end face, and single-mode optical fiber is used to receive resonant enhanced optical signal, and output;Straight waveguide is arranged on the fiber end face, for transmitting optical signal;Micro-ring waveguide is arranged on the fiber end face, and there is a coupling gap between micro-ring waveguide and straight waveguide, micro-ring waveguide selects optical signal passing through straight waveguide according to specific wavelength, and resonant enhances selected optical signal, short tube carbon nanotube nanometer film is coated on micro-ring waveguide, for absorbing heat.The application is used to solve the technical problems, such as lower tuning efficiency of existing optical filter, greater integration difficulty, to achieve the purpose of simpler integration method, broader tuning range and faster response speed compared with existing on-chip tunable filter.

The embodiment of the application provides an antenna system, relates to the technical field of terminals, and solves the problems of device customization difficulty, antenna cost and area limitation under the combination of LB+LB and 4*4 MIMO of a 5G terminal device. The specific scheme is as follows: a first tunable phase-shifting circuit is used for adjusting the frequency when a first antenna receives a signal, so as to receive a first double-frequency signal from the first antenna; a first tunable power divider is used for adjusting the frequency of a radio frequency channel between the first antenna and an integrated module; the first double-frequency signal received from the first tunable phase-shifting circuit is separated into a first frequency signal and a second frequency signal and transmitted to the first antenna integrated module; the first antenna integrated module is used for combining the two signals into a second double-frequency signal through a radio frequency integrated module first tunable filter; and the first tunable filter is used for outputting the second double-frequency signal on different radio frequency channels according to the frequency. The embodiment of the application is used for terminal device downlink reception control.

The invention relates to an acousto-optic tunable filter (AOTF). The acousto-optic tunable filter (AOTF) is an electric control tunable spectrum light splitting element, and the diffraction performance of an AOTF device is influenced by the sound field distribution in the AOTF. Sound field distribution in an existing AOTF device mainly considers that a sound field only comprises a single sound mode which is propagated in a specific direction and has a single wavelength. Therefore, the invention provides the analysis method for the acoustic mode distribution in the AOTF device, and the amplitude of each acoustic mode in the AOTF device is solved and obtained by establishing a non-homogeneous linear equation set through the elastic mechanical boundary condition of the AOTF device and the anisotropic solid constitutive equation. Compared with an existing AOTF device internal sound field modeling method, the AOTF device internal sound mode distribution analysis method provided by the invention has the advantages that a three-dimensional steady-state sound field in the AOTF device can be dispersed into superposition of different sound modes; the method can effectively calculate and analyze the influence of multiple reflections and mode conversion of sound waves on each solid surface of the AOTF device on sound field distribution, and is suitable for any crystal material.

Certain aspects of the present disclosure are directed towards an apparatus for wireless communication. The apparatus generally includes: a first receive chain including a first tunable filter; a second receive chain including a second tunable filter, wherein at least one of the first tunable filter or the second tunable filter is configured to receive control signaling to configure the at least one of the first tunable filter or the second tunable filter in one of multiple configurations including a first configuration for processing a signal within a first band, a second configuration for processing a signal within a second band, and a third configuration for processing a signal within a wide band spanning the first band and the second band; and a switch circuit coupled to the first receive chain and the second receive chain.

The invention discloses an adjustable resonant filter and a communication system, and relates to the technical field of communication, and the disclosed tunable filter comprises an optical resonant structure and at least one layer of lithium niobate film. The lithium niobate thin film is arranged in an optical resonance structure; the lithium niobate film is electrically connected with the electrode; the tuning voltage applied by the electrode is received through the lithium niobate film, and the refractive index is changed based on the electro-optical effect generated by the tuning voltage, so that the resonant wavelength of the optical resonant structure is adjusted. The electro-optical effect of the lithium niobate film is directly utilized, and the refractive index of the lithium niobate film can be instantaneously changed by applying an electric field, so that tuning of resonant wavelength is realized, physical process time required by mechanical movement or an electrothermal effect is avoided, and the response speed is effectively improved.

The invention discloses a Doppler velocity measurement system based on whispering gallery microcavity Brillouin laser, and belongs to the technical field of laser detection. The system comprises an echo wall microcavity Brillouin laser implementation unit, a light selection and amplification unit and a Doppler velocity measurement unit. Pump light is input into a high-quality factor echo wall microcavity through evanescent coupling, a cascade stimulated Brillouin scattering process is stimulated, and narrow-linewidth cascade Brillouin laser is generated; a tunable filter is used for screening out specific-order laser, and the specific-order laser is amplified by an erbium-doped optical fiber amplifier to serve as a detection light source; and after the probe light is reflected by the moving target, feedback light carrying Doppler frequency shift is re-injected into the microcavity and generates a self-mixing interference beat frequency signal with laser in the cavity, and finally the target speed is demodulated through photoelectric detection and spectral analysis. According to the invention, the microcavity enhancement effect and the cascade Brillouin process are utilized to narrow the line width, and the self-mixing interference structure is combined, so that laser Doppler velocity measurement with high resolution, high signal-to-noise ratio, compact structure and strong robustness is realized.