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105 results about "Tuned filter" patented technology

In signal processing, a tuned filter is a stage in the processing channel which accepts or rejects signals which are tuned for a specific type.

Intelligent suppression management system and method for radio frequency signal interference based on image recognition

The invention discloses a radio frequency signal interference intelligent suppression management system and method based on image recognition. The system comprises a multi-source sensing module, a fusion analysis module, a dynamic suppression module and an execution feedback module. The multi-source sensing module forms a radio frequency original signal set containing frequency spectrum features and time domain waveforms; the fusion analysis module receives the radio frequency original signal set and extracts an interference source feature vector in the radio frequency original signal set through a pre-trained convolutional neural network to generate a fusion decision signal; the dynamic suppression module receives the fusion decision signal and activates a corresponding algorithm in a preset suppression strategy library according to the interference type identifier; and the execution feedback module receives the real-time control signal and drives the tunable filter, the phased-array antenna and the power amplifier to execute interference suppression operation. According to the intelligent suppression management system and method for the radio-frequency signal interference based on image recognition, the problems of fuzzy positioning of the radio-frequency interference source, single suppression strategy and lack of environmental perception capability can be solved.
Owner:BEIJING GOLDARY CENTURY HIGH TECH CO LTD

Front-end module for a wireless communication device

A front-end module comprising a signal input configured to receive a radio-frequency (RF) signal, an antenna switch module (ASM), a power amplifier adapted to amplify the received RF signal to provide an amplified RF signal supplied to the ASM by way of one or more RF signal paths, and a tunable filter with selective coupled resonances. The selective coupled resonances are adapted to filter the RF signal output by the ASM to provide a filtered RF signal at an antenna node forming a signal output of the front-end module and configured to be coupled to an antenna.
Owner:SKYWORKS SOLUTIONS INC

Radio frequency front-end transmitting link and state detection method thereof

The invention relates to a radio frequency front-end transmitting link and a state detection method thereof, the transmitting link adopts four-stage series power amplification circuits, and the four-stage series power amplification circuits comprise a first-stage power amplification circuit, a second-stage power amplification circuit, a third-stage power amplification circuit and a fourth-stage power amplification circuit; the first-stage power amplification circuit is composed of a first pi attenuator and a low-noise amplification chip and used for radio frequency small signal gain amplification. The second-stage power amplification circuit is formed by cascading a temperature compensation attenuator, a filter and a gallium arsenide power amplifier tube, and the filter is a broadband filter, a tuned filter or a frequency hopping filter; the third-stage power amplification circuit is formed by cascading a numerical control attenuator and a three-stage gallium nitride power amplifier tube; and the fourth-stage power amplification circuit is formed by cascading a second pi-type attenuator and a last-stage gallium nitride power amplifier tube. The method has the advantages of being high in dynamic range and good in adaptability in a software radio system.
Owner:SHANGHAI JIEFANG INFORMATION TECH CO LTD

Double-light-path gas detection alarm device based on intermediate infrared SLD

The invention discloses a dual-optical-path gas detection alarm device based on an intermediate infrared SLD, and relates to the technical field of gas safety monitoring and alarm, in particular to the dual-optical-path gas detection alarm device based on the intermediate infrared SLD. In order to solve the problems that an existing gas alarm device is high in false alarm rate and delayed in response, and cannot realize multi-component gas concentration threshold value judgment and sound-light alarm linkage at the same time, the invention provides a dual-light-path gas detection alarm device based on an intermediate infrared SLD. Comprising an SLD light source module, an optical beam splitting and transmission module, a multi-reflection gas absorption cell, a main tunable filter array, a main photoelectric detector array, a reference tunable filter array, a reference photoelectric detector array, a differential amplifier array, a signal processing module, a display module and an alarm module. The method is suitable for the application fields of petroleum, natural gas, mining, underground space operation and the like.
Owner:CHANGCHUN UNIV OF SCI & TECH

Tunable filter bank for enhancing out-of-band rejection

The invention relates to a tunable filter bank for enhancing out-of-band rejection. The tunable filter bank comprises a first path switching module, a first filter bank, a second path switching module, a third path switching module, a second filter bank and a fourth path switching module, the first path switching module, the second path switching module, the third path switching module and the fourth path switching module are sequentially connected, and the first filter bank is connected between the first path switching module and the second path switching module. And the second filter bank is connected between the third path switching module and the fourth path switching module. The circuit can be equivalent to one or more of a high-pass filter, a low-pass filter, a transmission line and a band-pass filter, can process signal waveforms in different frequency band ranges, and has the characteristics of high control precision and high reliability.
Owner:XIDIAN UNIV

Back-driving tunable FP filter

The present invention provides a reverse-driven tunable F-P filter and a preparation method thereof, wherein the filter comprises a static mirror, a moving mirror, a supporting bridge pier, a microbridge, an electrode supporting structure and a top electrode; wherein the supporting bridge pier is prepared on the static mirror, and a cavity is formed between the supporting bridge pier and the static mirror; the moving mirror is located in the cavity, and an F-P resonant cavity is formed between the moving mirror and the static mirror, and a first stopper is prepared on the static mirror to prevent the moving mirror from contacting the static mirror; the microbridge comprises a central part and an edge part, wherein the central part is prepared on the side of the moving mirror facing away from the static mirror, and the central part acts as a bottom electrode for adsorption with the top electrode; the edge part is prepared on the top of the supporting bridge pier, and the electrode supporting structure is supported between the edge part and the top electrode. The present invention can determine the minimum cavity length by using a reverse driving method, and drives the moving mirror in the opposite direction of the static mirror, thereby overcoming the problem of adsorption instability in principle, thereby expanding the spectral detection range by increasing the cavity length tuning range.
Owner:CHANGCHUN INST OF OPTICS FINE MECHANICS & PHYSICS CHINESE ACAD OF SCI

Device and method for rapidly screening linewidth of single crystal resonator for magnetic tuning filter

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.
Owner:SOUTHWEST INST OF APPLIED MAGNETICS

An adjustable n-path reflectionless filter and superheterodyne receiver

The application relates to the technical field of tunable N-path filter, in particular to a tunable N-path reflection-free filter and a superheterodyne receiver. The tunable N-path reflection-free filter comprises a signal source, an N-path band-pass filter unit, an N-path band-stop filter unit, an output resistor and a phase-splitting clock generating circuit. The output end of the signal source is connected with one end of the N-path band-pass filter unit and the N-path band-stop filter unit respectively, the other end of the N-path band-stop filter unit is connected with the output resistor, the gate of a plurality of MOS switches in the N-path band-pass filter unit and the N-path band-stop filter unit is connected with the phase-splitting clock generating circuit, and the phase-splitting clock generating circuit outputs a control signal. The tunable N-path reflection-free filter provided by the application has excellent frequency selectivity, can effectively suppress high-order harmonics, and can adjust the passband and the stopband by changing the switching frequency. Meanwhile, the filter can eliminate the reflected signal, prevent the intermodulation interference and gain fluctuation of the mixer and the high-gain amplifier in the system.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Radio site monitoring device

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.
Owner:RF IND

Dual-passband filter with adjustable center frequency and bandwidth

PendingCN119495918AImprove out-of-band rejection performanceLarge tuning rangeWaveguide type devicesFeeder lineSoftware engineering
The invention discloses a dual-passband filter with all adjustable center frequency and bandwidth, and aims to provide a band-pass filter with low loss and wide tuning range. According to the technical scheme, each part comprises an input port, an output port, a coupled feeder line, a quarter-wavelength resonator with a variable capacitance diode loaded at the tail end, and a branch resonator with a variable capacitance diode loaded. According to the structure, a coupling line connected with a source and a load is adopted to feed a resonator in a slot coupling mode, the capacitance value of a variable capacitance diode is changed, and finally, the bandwidth and the center frequency are tunable. According to simulation verification, the center frequency of a high pass band of the all-tunable filter disclosed by the invention is continuously adjustable within 2.39-2.61 GHz, and at the moment, the center frequency of a low pass band is kept unchanged at 1.61 GHz and the bandwidth of 120 MHz; the center frequency of the low pass band is continuously adjustable within 1.45 GHz-1. 8GHz, and the center frequency of the high pass band is kept unchanged at 2.51 GHz and the bandwidth of 107MHz; the bandwidth of the high pass band is tunable in the range of 83-132MHz, the insertion loss fluctuates in the range of 1.16-1.45 dB, and at the moment, the center frequency of 1.6 GHz and the bandwidth of 122MHz of the low pass band are kept unchanged. The result shows that the microstrip filter with the tunable center frequency and bandwidth has the advantages of low loss, wide tuning range and wide application range.
Owner:YUNNAN UNIV

Optimization design method of double-tuned filter for converter station

An optimization design method of a double-tuned filter for a converter station comprises the following steps: calculating a total impedance function Z (omega) of the double-tuned filter; representing two tuning points of the filter through a full impedance function Z (omega) of the double-tuned filter, and defining an intermediate angular frequency of the double-tuned filter; the value of a high-voltage side capacitor C1 is determined according to the fundamental wave reactive compensation quantity QS1, and the values of L1, L2 and C2 are solved; and calculating the fundamental wave power loss of the medium resistor R of the double-tuned filter and the harmonic amplification coefficient H (omega) of the characteristic harmonic voltage of the AC filter of the converter station. And with the filtering performance, the resonance-free risk and the equipment investment cost as constraint conditions, the values of L1, L2 and C2 are optimized by adopting an optimization algorithm. According to the method, the optimal design process of an existing double-tuned filter topological structure for the converter station is analyzed in detail by considering the filtering effect and the harmonic amplification effect and combining the circuit principle, the filtering effect of the double-tuned filter for the converter station can be improved, and the harmonic resonance or harmonic amplification risk is avoided.
Owner:CHINA THREE GORGES UNIV +1

A brillouin fiber laser narrow-band tunable double-pass microwave photonic filter

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.
Owner:ZHONGBEI UNIV

Generation system and generation method of three-band coherent microwave signal

The invention relates to a generation system and a generation method of a three-band coherent microwave signal. The system comprises a laser, an electro-optical modulator, an optical fiber ring, a photoelectric detector, a first bridge, a second bridge, a first broadband filter, a second broadband filter, a third broadband filter, a tunable filter, a first amplifier, a second amplifier, a third amplifier, a fourth amplifier, a coupler, an external signal source, a signal generator and the like. The generating system disclosed by the invention is a Fourier domain mode-locked photoelectric oscillator system for generating coherent microwave signals of three frequency bands based on difference frequency injection locking, and a Fourier domain mode-locked photoelectric oscillator autonomously-generated signal is combined with an external injection signal; therefore, multiple frequency band sweep frequency signals with good coherence and strong tunability can be output at the same time. The generated microwave signals of three frequency bands have good tunability and coherence, and the formed three-loop Fourier domain mode-locked optoelectronic oscillator system can be applied to multiple fields.
Owner:HEBEI UNIVERSITY

Adjustable N-path non-reflection filter and superheterodyne receiver

The invention relates to the technical field of tunable N-path filters, in particular to an adjustable N-path non-reflection filter and a superheterodyne receiver, the adjustable N-path non-reflection filter comprises a signal source, an N-path band-pass filtering unit, an N-path band-stop filtering unit, an output resistor and a split-phase clock generation circuit; wherein the output end of the signal source is connected with one end of the N-path band-pass filtering unit and one end of the N-path band-stop filtering unit, the other end of the N-path band-stop filtering unit is connected with the output resistor, and the split-phase clock generation circuit is connected with grid electrodes of a plurality of MOS switches in the N-path band-pass filtering unit and the N-path band-stop filtering unit and outputs control signals. The adjustable N-path non-reflection filter provided by the invention has excellent frequency selectivity, can effectively suppress higher harmonics, and can adjust a pass band and a stop band by changing the switching frequency. Meanwhile, the filter can eliminate reflected signals and prevent the reflected signals from inducing a mixer and a high-gain amplifier in a system to generate intermodulation interference and gain fluctuation.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Double-tuned filter and elevator permanent magnet synchronous traction control system

The invention discloses a double-tuned filter, which comprises a filter module and a switch, and is characterized in that the filter module comprises a first series group which is formed by connecting a first inductor, a first resistor and a second capacitor in series; the second series group is formed by connecting a second inductor and a second resistor in series; the first series group and the second series group are connected in parallel and then are connected in series with the first end of the first capacitor; and the second end of the first capacitor is connected in series with the first end of the switch. By introducing the double-tuned filter, harmonic suppression of characteristic frequency generated by an elevator frequency conversion system during constant-speed operation of an elevator is realized, so that torque pulsation generated during constant-speed operation of an elevator permanent magnet motor is effectively suppressed, vibration and noise during operation of the elevator are reduced, and comfort of the elevator is improved. The invention further discloses an elevator permanent magnet synchronous traction control system.
Owner:SHANGHAI MITSUBISHI ELEVATOR CO LTD

BZT laminated dielectric film with low loss and high tuning rate and preparation method thereof

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.
Owner:DONGGUAN UNIV OF TECH

Capacitance setting method and equipment of filter and storage medium

The invention discloses a capacitance setting method and device for a filter and a storage medium, and the method comprises the steps: calculating a working current flowing through a single-tuned filter under the condition that a harmonic wave is injected into the single-tuned filter; the single tuned filter comprises a capacitor and a reactor; calculating the rated capacity of the capacitor according to the working current; according to the rated capacity of the capacitor, calculating the rated voltage which can filter harmonic waves and is minimum in capacity for the capacitor; and setting the minimum capacity of the capacitor according to the rated voltage of the capacitor. According to the embodiment of the invention, the minimum capacity of the capacitor is calculated under the condition of keeping the harmonic filtering effect of the capacitor of the single-tuned filter, and the cost of the capacitor can be reduced, so that the cost of the single-tuned filter is reduced, and the cost is reduced on a large scale when a large number of low single-tuned filters are deployed in a power distribution network.
Owner:GUANGDONG POWER GRID CO LTD +1

Method and device for tuning ANC based on hearing threshold level

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.
Owner:HARMAN INT IND INC

Tunable laser with channel selector

Systems and methods here may include improved tunable lasers having a tunable filter and a tunable channel selector that can control precisely the wavelength and the bandwidth of the light emitted by the laser, while suppressing light that may otherwise be emitted by the laser outside the desired wavelength and bandwidth with unidirectional ring lasers having a resonator of which forms a ring and where light propagates only in one of the two possible directions.
Owner:MONARCH QUANTUM INC

Band-pass filter free of fundamental wave loss and low in parallel resonance

The invention relates to the technical field of power grid harmonic suppression, in particular to a fundamental-loss-free low-parallel-resonance band-pass filter which comprises a first single-tuned filter Hn1 and a second single-tuned filter Hn2 which are arranged in parallel, and the series resonance frequencies of the first single-tuned filter Hn1 and the second single-tuned filter Hn2 are different. A group of resistors R1 is bridged between the first single-tuned filter Hn1 and the second single-tuned filter Hn2; the first single-tuned filter Hn1 comprises a first capacitor C11, a second capacitor C12 and a first reactor L1, the first capacitor C11, the second capacitor C12 and the first reactor L1 are connected in series, the second single-tuned filter Hn2 comprises a third capacitor C2 and a second reactor L2, and the third capacitor C2 and the second reactor L2 are connected in series; according to the invention, the structure is simple, the cost is low, the resistor R1 has no fundamental wave loss, the energy conversion efficiency of the whole power system is improved, the loss of energy in the transmission and treatment process is reduced, and the energy-saving effect is good.
Owner:NANJING GEZHI POWER TECH CO LTD

System and method for detecting junction temperature of LD chips in real time in batches

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.
Owner:BEIJING HEPLIN OPTOELECTRONICS TECHNOLOGY CO LTD

Radio frequency front end of radar receiver with large dynamic range

The invention discloses a radio frequency front end of a radar receiver with a large dynamic range, relates to the field of wireless communication, and aims to solve the problem that a third-order intercept point and a noise coefficient are difficult to meet indexes under the condition that an existing receiver meets high sensitivity. The method comprises the following steps: a receiving calibration switch selects to input an antenna signal and a calibration signal into a preposed step attenuator, the antenna signal and the calibration signal enter a numerical control tuned filter after impedance matching by a matching circuit, an output tuned and filtered signal enters a low-noise amplifier, and the signal after low-noise amplification and a receiving gate enter a frequency mixer after being selected by a transceiving switch; and the weak intermediate-frequency signal is subjected to signal intensity adjustment through the first amplifier and the rear step attenuator in sequence, and is processed by the crystal filter and the amplifier twice to output the intermediate-frequency signal. Under the condition of high sensitivity, the optimal signal-to-noise ratio can be obtained, the noise coefficient is reduced, the influence on a channel third-order intercept point index is reduced, and the harmonic suppression degree of an intermediate-frequency signal is improved.
Owner:BEIJING INST OF RADIO METROLOGY & MEASUREMENT

A non-disassembly direct identification method for characteristic parameters of single-tuned filters

The present invention discloses a non-disassembly type direct identification method for characteristic parameters of a single-tuned filter, comprising the following steps: detecting the current of the single-tuned filter by using a current detection system, initializing the single-tuned filter to be tested to a zero state, applying a DC voltage source with a constant amplitude to the single-tuned filter to be tested, sampling its current and saving the sample, calculating a basic coefficient, a basic factor and an average basic factor, calculating an average estimated dynamic factor, calculating an estimated factor, and calculating the capacitance value, the inductance value and the resistance value of the single-tuned filter; the present invention takes the single-tuned filter as a detection object, monitors its characteristic parameters in real time, constructs a simulation model of the single-tuned filter, and verifies the identification method of the characteristic parameters in the filter through experiments. By analyzing the experimental results, it is confirmed that the identification method of the present invention can accurately estimate the size of the characteristic parameters of the single-tuned filter without disassembling or damaging the filter device.
Owner:XIHUA UNIV

Low-frequency low-noise tuning amplification system

PendingCN119675598AEliminate the influence of incoming noisePrevent amplification and saturationMultiple-port networksAmplifier modifications to reduce noise influenceLow noiseNoise
The invention discloses a low-frequency low-noise tuning amplification system, which relates to the technical field of low-frequency communication and comprises a control isolation driving circuit, a controllable attenuator group, a single-tuned filter and a low-noise amplifier, the input end of the control isolation driving circuit is connected with a control signal, the first output end of the control isolation driving circuit is connected with the first input end of the single tuned filter through the controllable attenuator group, and the control isolation driving circuit is used for carrying out signal attenuation on the first path of control signal to obtain an attenuated control signal; the second output end of the control isolation driving circuit is connected with the second input end of the single tuned filter; the single tuned filter is used for isolating the attenuated control signal and performing gain amplification, and performing gain amplification according to the second path of control signal to obtain a tuned output signal; and the low-noise amplifier is used for amplifying the tuned output signal. According to the invention, through the controllable attenuator, amplification saturation when signals and noise are too large is prevented; the single tuned filter has signal amplification gain and out-of-band rejection capability, so that the anti-interference performance of the low-frequency receiving front end is effectively improved; the digital control signal is isolated by controlling the isolation drive circuit, the influence of noise introduced by an external digital circuit is eliminated, and the anti-interference capability is improved.
Owner:WUHAN SHIP COMM RES INST (NO 722 RES INST OF CHINA STATE SHIPBUILDING CORP)

Front-end module for a wireless communication device

A front-end module comprising a signal input configured to receive a radio-frequency (RF) signal, an antenna switch module (ASM), a power amplifier adapted to amplify the received RF signal to provide an amplified RF signal supplied to the ASM by way of one or more RF signal paths, and a tunable filter with selective coupled resonances. The selective coupled resonances are adapted to filter the RF signal output by the ASM to provide a filtered RF signal at an antenna node forming a signal output of the front-end module and configured to be coupled to an antenna.
Owner:SKYWORKS SOLUTIONS INC

Multiband reconfigurable fourier mode-locked optoelectronic oscillator

The present application relates to a kind of multi-band reconfigurable fourier mode-locked optoelectronic oscillator, its structure includes laser, electro-optic modulator, photodetector, first A low noise amplifier, first multiplexer, second multiplexer, filter amplification branch, arbitrary waveform generator and electric power divider etc., wherein, first multiplexer, second multiplexer, the N filter amplification branches connected therebetween and arbitrary waveform generator jointly constitute multi-band reconfigurable filter module.The present application sets up multiple filter amplification branches in optoelectronic feedback oscillation loop, thereby constructs a multi-band fourier mode-locked oscillation loop cavity, the frequency range and period of multi-band reconfigurable microwave signal are determined by the sweep width and period of tunable filter in each filter amplification branch in multi-band reconfigurable filter module.Thereby for anti-radar or anti-jamming communication system provides a high-quality microwave signal source.
Owner:HEBEI UNIVERSITY

Tunable intermediate infrared fiber laser with high power flatness

PendingCN121261182AActive medium shape and constructionLaser low energyGain
The invention discloses a tunable mid-infrared fiber laser with high power flatness. A pumping source enters an erbium-doped fiber through a pumping / signal coupler, and a low-reflectivity cavity mirror, the erbium-doped fiber, a laser collimator and a tuned filter form a laser resonant cavity; the low-reflectivity cavity mirror and the pumping / signal coupler are coupled to output intermediate infrared laser, the tuning filter device is used for realizing a wavelength tuning function, and the insertion loss difference value of the device under different working wavelengths is less than 0.5 dB; the wavelength of the pumping source is in a 1.6-1.7 micron wave band, erbium ions are pumped from a ground state energy level to a laser upper energy level, and laser lower energy level particles are consumed; the stable insertion loss in the process of adjusting the working wavelength by using a tuning filter device is combined with the characteristics that the emission cross section and the absorption cross section of erbium ions are gradually reduced along with the increase of the wavelength and the reduction rate of the absorption cross section is greater than that of the emission cross section, so that the gain difference caused by the emission cross section difference under different laser wavelengths of the fiber laser is reduced; and the power flatness of the fiber laser under different tuning wavelengths is improved.
Owner:TIANJIN UNIV

Structure for solving synchronous tuning of coaxial mechanical tuned filter

ActiveCN223680365UWaveguide type devicesSoftware engineeringCoaxial cavity
The utility model discloses a structure for solving synchronous tuning of a coaxial mechanically tuned filter, which belongs to the technical field of microwave filters and comprises five parallel coaxial cavities, tuning rods in the coaxial cavities, double-coupling hole structures between adjacent cavities and input and output structures. The cavity bodies of the five parallel-row coaxial cavities are the same in size and are symmetrically distributed, the number of the cavity bodies can be N, and the coaxial cavity bodies can be arranged in a parallel-row mode or other flexible modes. The tuning rods in the coaxial cavity are symmetrically distributed, the diameters of the tuning rods are different, the middle of the tuning rods is thick, and the two sides of the tuning rods are thin. The double-coupling junction hole structure between the adjacent cavities is formed by forming two regular coupling holes in the common wall of the adjacent cavities, and the coupling between the whole cavities is symmetrically distributed. By changing the diameter of the resonance rod in the coaxial cavity, the problem of asynchronous high-frequency mechanical tuning is solved, and meanwhile, the bandwidth difference in the whole tuning range can be reduced by adopting the double coupling holes.
Owner:THE 54TH RESEARCH INSTITUTE OF CHINA ELECTRONICS TECHNOLOGY GROUP CORPORATION

A parameter design method of a double-tuned filter with damping

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.
Owner:ZHONGHUI INTELLIGENT ELECTRIC (JIANGSU) TECH CO LTD

Giant magnetostrictive micro-strain unit, tunable filter and passband adjusting method

The invention discloses a giant magnetostrictive micro-strain unit, a tunable filter and a passband adjusting method, and belongs to the technical field of electronic devices and radio frequency communication. The giant magnetostrictive micro-strain unit is composed of an outer conductor, an inner conductor, a supporting structure and a driver. The driver is composed of a giant magnetostrictive material, an output structure, a framework, a coil and a fixing structure. The tunable filter comprises a plurality of giant magnetostrictive micro-strain units; according to the filter, the current input into the coil is controlled, the driving magnetic field of the giant magnetostrictive material is changed, and the giant magnetostrictive effect of the giant magnetostrictive material is utilized to enable the giant magnetostrictive material to generate micro-strain, so that the structure of the filter is adjusted to adjust the characteristics of the filter; the position of the inner conductor in the outer conductor is adjusted by adjusting the micro strain of a driver at the bottom of the micro coaxial inner conductor, so that the loss and out-of-band rejection characteristics are adjusted; the length of the resonant transmission line is adjusted by adjusting the micro-strain of the driver at the end part of the resonant transmission line, so that the resonant frequency and the bandwidth are adjusted.
Owner:BEIJING MAITIAN TONGXIN TECHNOLOGY CENTER (LLP)