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43 results about "Passive filtering" patented technology

A passive filter is a kind of electronic filter that is made only from passive elements – in contrast to an active filter, it does not require an external power source (beyond the signal). An active filter is a type of analog electronic filter, distinguished by the use of one or more active components and require an external power source.

SiC MOSFET conduction current extraction circuit and method

The invention relates to power semiconductor device on-line monitoring and power electronic system control, in particular to a SiC MOSFET conduction current extraction circuit and method, high-frequency oscillation interference is effectively suppressed through a second-order passive RC filter circuit, a measurement error less than or equal to 1.5% is realized within a current range of 50A-300A in combination with an accurate mathematical model established by a depth symbol optimization algorithm, and the measurement accuracy is improved. The requirement of the intelligent gate driver on high-precision current feedback is met, and the measurement precision is remarkably improved; the pulse width direct analysis technology is adopted, a traditional active integrator and a digital decoding link are omitted, the system response delay is smaller than or equal to 500 ns, microsecond-level over-current protection can be supported, the response speed and the real-time performance are optimized, and the system safety in a high-frequency application scene is remarkably improved.
Owner:烟台哈尔滨工程大学研究院

Tunnel magnetoresistance array type magnetic anomaly detection device with low noise, high precision and low power consumption

The invention discloses a low-noise, high-precision and low-power-consumption tunnel magnetoresistance array type magnetic anomaly detection device, and relates to the field of geomagnetic field magnetic anomaly detection. In order to overcome the defects that in the prior art, the detection precision is insufficient, the noise level is high, power consumption is large, and long-time stable operation is difficult to consider, the technical scheme provided by the invention is that a signal acquisition and amplification circuit is composed of a plurality of triaxial tunnel magnetoresistive sensors, an isolation circuit, an instrument amplification circuit and a passive filter circuit; the master control and signal processing circuit is composed of a high-precision analog-to-digital conversion circuit, a clock circuit and a microprocessor circuit. The signal transmission circuit is composed of an Ethernet module and is used for transmitting the processed data to an upper computer; the power supply module is composed of a low-noise low-dropout voltage stabilizing circuit and a reference voltage circuit, and is used for providing a stable power supply and a unified reference voltage. The method is suitable for long-time high-precision geomagnetic anomaly detection work in geophysical exploration, national defense safety monitoring and complex environments.
Owner:HARBIN ENG UNIV

Passive low-harmonic frequency converter special for rail transit air conditioner

The utility model belongs to the technical field of electronic circuit, especially relates to a passive low harmonic frequency converter special for rail transit air conditioner. The frequency converter includes: passive filter module, rectifier module, precharge module, voltage-sharing filter module, inverter module and control module. The input end of passive filter module is connected to the output end of alternating -current source, and the output end is connected to the input end of rectifier module, and the output end of rectifier module is connected to the input end of precharge module, the output end of precharge module is connected to the input end of voltage-sharing filter module, the output end of voltage-sharing filter module is connected to the input end of inverter module, and the output end of inverter module is the voltage output end of passive low harmonic frequency converter special for rail transit air conditioner, and inverter module and control module are connected through inverter control and protection circuit. The utility model can reduce the harmonic interference of frequency converter inverter to input power grid, protects the electrical equipment on power grid, and improves the security of operation.
Owner:SHEN ZHEN NEW ENERGY ANHUA TECH CO LTD

Optical filter and spectrometer

The utility model discloses an optical filter and a spectrograph, the optical filter (100) comprises multiple stages of passive filtering units (300), in two adjacent stages of passive filtering units (300), the output end of the previous stage of passive filtering unit (300) is connected with the input end of the next stage of passive filtering unit (300), and the output end of the next stage of passive filtering unit (300) is connected with the output end of the next stage of passive filtering unit (300). The passive filtering unit (300) is used for filtering and modulating an incident optical signal, so that the optical signal processed by the previous-stage passive filtering unit (300) enters the next-stage passive filtering unit (300), and the passive filtering unit (300) is used for filtering and modulating the incident optical signal; and the multiple stages of passive filtering units (300) are respectively used for modulating light with different wavelengths. The optical filter and the spectrometer provided by the utility model have the advantages of low power consumption and miniaturization.
Owner:GLITTERINTECH (XUZHOU) LTD

Multi-tuning composite passive filtering device and intelligent switching control system and method thereof

The invention provides a multi-tuning composite passive filtering device and an intelligent switching control system and method thereof, and belongs to the field of passive filtering. The device comprises a plurality of groups of single-tuned filters and a group of C-type filters which are connected in parallel to a traction network, the front end of each branch is provided with a fling-cut switch which is used for cooperatively inhibiting multi-frequency harmonic waves and providing reactive compensation, and the system is used for controlling the switching of passive filters of each branch. By collecting system voltage, current of each branch, element temperature and switching state in real time and utilizing a digital signal processor to carry out fast Fourier transform and comprehensive state diagnosis, faults such as detuning, failure and overload of filter branches and the change trend of system harmonic waves can be intelligently judged; based on a diagnosis result, the system can automatically execute a protective removal or optimization switching strategy; according to the invention, upgrading from passive filtering to active early warning and intelligent treatment is realized, and the problem of system resonance risk possibly caused by filter performance reduction and continuous access is fundamentally solved.
Owner:SCI & TECH RES INST OF DAQIN RAILWAY CO LTD +2

Power filter with signal masking function

The invention relates to the technical field of power supply filtering, and discloses a power supply filter with a signal masking function, which comprises a shell module for packaging each functional module and providing electromagnetic shielding; the passive filtering module performs primary filtering on a power supply signal to reduce low-frequency and intermediate-frequency noise; the signal sampling and spectrum analysis module samples and analyzes the frequency domain characteristics of the power supply signal, and extracts a target frequency band signal; the abnormal signal identification module identifies and judges abnormal coupling signals; the interference signal generation module generates a masking signal to suppress an abnormal signal; the closed-loop feedback control module adjusts parameters of the passive filtering and interference signal generation module in real time; and the output and verification module outputs and verifies the processed signal effect. The closed-loop feedback control technology is adopted, the technical effect of optimizing the system performance is achieved by monitoring the working state of the system in real time and dynamically adjusting the parameters of the filter and the interference signal module, and the defect that a traditional method cannot adapt to different working conditions in real time is overcome.
Owner:拓达世纪信息产业有限公司

Low-channel EEG amplification circuit and brain-computer interface device for behind-the-ear EEG signals

The present application relates to the technical field of wireless communication networks, and provides a low-channel EEG amplification circuit and a brain-computer interface device for behind-the-ear EEG signals, comprising: a dry electrode sensing module for acquiring EEG signals; a pre-active amplifier module comprising an operational amplifier circuit with high input impedance; an anti-aliasing filter module composed of a multi-order passive filter network and an active filter circuit in cascade, connected to the output end of the pre-active amplifier module, for filtering out high-frequency interference signals; a right leg drive feedback module comprising a programmable impedance adjustment circuit and a current limiting protection circuit, forming a closed-loop feedback loop with the pre-active amplifier module, and the output end of the right leg drive feedback module forming a current loop with the human body through a protective resistor; an analog-to-digital conversion module using an integrated low-power analog front-end chip; a wireless transmission module; and a power management module providing independent power supply to the analog front-end chip, the operational amplifier circuit, and the wireless transmission module.
Owner:XIAOZHOU TECH CO LTD

Three-phase input filter circuit

The utility model relates to a three-phase input filter circuit, which comprises three multi-stage filter units and three discharge units, a, B and C phases of a power supply side are respectively connected with the three-phase bridge rectification unit through the three multi-stage filtering units; the A phase, the B phase and the C phase of the power supply side are respectively connected with the N phase of the power supply side through the three multi-stage filtering units and the three discharging units; according to the utility model, the three filtering units are arranged at the input side of the three-phase power supply, the three filtering units are used for filtering the three input phases of the three-phase power supply, i.e., the A, B and C phases respectively, the current harmonic pollution at the power grid side is reduced, the reactive power is reduced, the filtering circuit is introduced at the input side, and the harmonic pollution is eliminated through the passive filtering technology. Therefore, power quality is improved.
Owner:SHENZHEN ZHENHUA MICROELECTRONICS

A boost circuit with adjustable charge-discharge frequency

The application discloses a boost circuit capable of realizing adjustable charging and discharging frequency, comprising a charging and discharging circuit main body, three groups of optional passive RC filter circuits, a secondary passive filter and source follower circuit, a combination logic and differential pulse generation circuit and a negative feedback circuit. The charging and discharging circuit main body comprises two sub-circuits, the three groups of optional filter circuits are combined by switches and resistors and capacitors, and the negative feedback circuit controls the differential pulse signal by a comparator to adjust the charging and discharging. The circuit can realize the switching of three charging and discharging frequencies of 30 MHz, 100 MHz and 400 MHz, is stably boosted to 1.6 V-2.2 V, effectively controls dynamic noise and is suitable for application scenarios of low power supply voltage.
Owner:ZHONGYIN MICROELECTRONICS (CHENGDU) CO LTD

Full-band compact hybrid emi filter circuit design method based on current feedback

This invention proposes a design method for a full-band compact hybrid EMI filter circuit based on current feedback. The method includes: constructing an electromagnetic interference test circuit to obtain the common-mode EMI spectrum required for attenuation by the PWM converter, and establishing a high-frequency equivalent circuit for the PWM converter; obtaining the optimal hybrid EMI filter topology based on the high-frequency equivalent models of active and passive EMI filter circuits and the noise attenuation characteristics of the hybrid EMI filter circuit topology; designing the active EMI filter topology and its high-frequency equivalent model based on the noise cancellation principle of the active EMI filter and the common-mode EMI spectrum; designing the active EMI filter topology based on the noise cancellation principle of the active EMI filter and the common-mode EMI spectrum; designing the passive EMI filter structure based on the common-mode EMI noise spectrum after adding the active EMI filter; and designing the hybrid EMI filter circuit based on the hybrid EMI filter topology, the active EMI filter topology, the passive EMI filter structure, and the high-frequency equivalent models of the active and passive EMI filter circuits.
Owner:BEIJING JIAOTONG UNIV

Filtering device for processing thickening agent

The utility model belongs to the technical field of thickening agent processing equipment, and particularly relates to a filtering device for thickening agent processing, which comprises an equipment main body, a supporting pulley block, a sliding control table and a cylinder, the supporting pulley block is arranged at the upper end of the equipment main body, the sliding control table is arranged at the upper end of the supporting pulley block, and the cylinder is arranged at the upper end of the sliding control table. Through the arrangement of the sliding rail, the sealing cover, the spring column, the extrusion disc and the collection bin, when the equipment is used, an operator controls the air cylinder through the sliding control table, the operator firstly pours a thickening agent into the screen in the equipment main body, then closes the sealing cover and pushes the sliding control table, and then the thickening agent is squeezed out. The sliding control table slides on the sliding rail under the supporting of the supporting pulley block, so that the equipment can actively apply pressure to the filtering operation of the thickening agent, compared with a traditional passive filtering mode, the active pressure applying filtering can greatly improve the filtering speed of the thickening agent, the automation degree of the step is high, and extra labor cost does not need to be input.
Owner:YIWEILONG (XIAMEN) BIOTECHNOLOGY CO LTD

Air conditioning equipment

The present invention provides an air conditioning apparatus provided with a radar sensor and a processing device, the air conditioning apparatus comprising: an active intervention module comprising: a passive filtering unit configured to filter coarse interference in detection data; the coarse interference comprises that the movement information coordinate exceeds a preset physical area, the collection time of the movement information exceeds a preset activity time period, and / or the movement information track exceeds a moving object of a preset track area, and establishing an original data set; the collection unit is configured to allocate suspiciousness for areas in the air-conditioned room based on the motion trail of the moving object in the original data set, and establish a suspicious area set according to a suspiciousness preset condition; the active filtering unit is configured to supply air to the suspicious area set when the moving object is not detected, and judge the moving object detected under the air supply condition as a passive interference source; and the active filtering unit takes the moving object after the passive interference source is filtered as an effective element. The method can improve the long-term accuracy of detection.
Owner:QINGDAO HISENSE BOSCH AIR CONDITIONING SYSTEM CO LTD

Intelligent self-cleaning lampblack intercepting system based on bionic cilia array

The invention discloses an intelligent self-cleaning oil smoke interception system based on a bionic cilium array, which realizes graded efficient interception of oil smoke particles through the bionic multi-stage cilium array, and integrates intelligent control modules for self-adaptive vibration cleaning, cilium surface functional modification and airflow and temperature collaborative sensing. The system can sense the oil smoke load and cilium pollution state in real time and dynamically adjust the cleaning strategy; a micro-nano composite structure super-oleophobic coating is constructed on the surface of the cilia; and meanwhile, auxiliary electrostatic adsorption and a local heat energy field are introduced, so that the capture rate of ultrafine particles is remarkably increased, and oil drop desorption is accelerated. The interception efficiency, the self-cleaning capability and the intelligence are remarkably improved, and the passive filtering mode of a traditional range hood is thoroughly changed.
Owner:IMAGIC KITCHEN APPLIANCES CO LTD

Signal processing method, controller and building control system

The invention provides a signal processing method, a controller and a building control system, and relates to the technical field of building control. The method comprises the following steps: receiving a to-be-processed signal of a sensor, wherein the to-be-processed signal comprises a target signal and an interference signal collected by the sensor; analyzing the to-be-processed signal to determine an interference signal feature in the to-be-processed signal, the interference signal feature in the to-be-processed signal including at least one of a peak fluctuation feature and a waveform similarity feature; judging whether the to-be-processed signal contains a periodic interference signal or not according to the interference signal characteristics in the to-be-processed signal; and under the condition that the to-be-processed signal contains the periodic interference signal, the filter circuit is regulated and controlled according to the characteristics of the periodic interference signal. Through the method, the interference signal of the sensor signal can be accurately identified in real time, and filtering is performed in a targeted manner, so that the problems of sensor signal loss and non-ideal filtering effect caused by passive filtering can be solved.
Owner:GREE ELECTRIC APPLIANCE INC OF ZHUHAI

High-resolution double-beam fundamental transverse mode semiconductor laser chip

The invention provides a high-resolution double-beam fundamental transverse mode semiconductor laser chip, and relates to the technical field of semiconductor lasers. The high-resolution double-beam fundamental transverse mode semiconductor laser chip comprises a chip body, and a first ridge-type waveguide and a second ridge-type waveguide are formed on the upper side of the chip body through one-time etching. Each of the first ridge waveguide and the second ridge waveguide sequentially comprises an active oscillation waveguide area, a passive filtering waveguide area and an active amplification waveguide area in the light emitting direction. The first ridge-type waveguide and the second ridge-type waveguide intersect, and the intersection point is located in the passive filtering waveguide area. And the upper side surfaces of the active oscillation waveguide region and the active amplification waveguide region are provided with P-plane metal connected with the electrodes. An insulating layer is arranged on the upper side face of the chip body, and the P-face metal is exposed outside through an avoiding notch in the insulating layer. The output light spot of the chip is a pure fundamental mode light spot, so that the resolution of the printer can be effectively improved.
Owner:Shandong Huaguang Optoelectronics Co. Ltd.

A high-precision wide-range current measurement device without switching and a signal processing method

The present application belongs to the field of precision testing technology and instrument, the traditional non-contact current detection meets the basic demand of power monitoring to a certain extent, but when facing the complex and changeable measurement environment and the growing measurement precision requirement, the limitation gradually appears. The present application provides a high-precision large-range current measurement device and signal processing method without switching, through a high-sensitivity signal sampling unit, high-precision sampling of small current analog signals is realized, and two-stage passive filter circuit is added to the signal sampling unit to filter most of the clutter in the analog signal, the digital signal processing method is used in MCU to filter the digital current data with higher precision, the digital signal processing technology is applied to the field of current detection, through optimizing the detection circuit structure and signal processing process, high-precision and high-efficiency current measurement is realized.
Owner:TAIYUAN UNIVERSITY OF TECHNOLOGY

Intelligent collaborative harmonic suppression method and related equipment

The invention discloses an intelligent cooperative harmonic suppression method and related equipment, and the method comprises the steps: obtaining a voltage signal and a current signal, and carrying out the preprocessing, and obtaining the preprocessing data; performing spectrum analysis on the preprocessed data to obtain spectrum data of a plurality of harmonic waves; based on the frequency spectrum data, determining governance weights corresponding to the passive filtering unit, the active filtering unit and the reactor unit respectively; and based on the governance weight, respectively adjusting a capacitance parameter of the passive filter unit, a compensation current parameter of the active filter unit and an impedance parameter of the reactor unit. According to the invention, harmonic wave coverage in a wide frequency range is realized through an intelligent adaptive filtering mode, load fluctuation and power grid frequency deviation are adapted, the harmonic wave treatment effect is more stable, the defects of a traditional harmonic wave treatment technology in coverage range, scene adaptability and volume cost are overcome, and harmonic wave treatment requirements of different scenes can be met.
Owner:SHENZHEN JUNAN ELECTRIC EQUIP CO LTD

Non-isolated unidirectional Boost converter and coupling inductor design method thereof

The invention provides a non-isolated unidirectional Boost converter and a coupling inductor design method thereof, the converter comprises a coupling inductor unit, a primary winding of the coupling inductor unit is used as an excitation inductor of the converter, and a secondary winding of the coupling inductor unit is connected in series with an auxiliary capacitor to form a passive filter branch; wherein the passive filtering branch is connected with an input power supply in parallel; the converter is configured to enable current flowing through the excitation inductor to flow bidirectionally by controlling alternate on-off of the first switch tube and the second switch tube, so that zero-voltage switching-on of the first switch tube or the second switch tube is realized; the passive filtering branch is configured to generate filtering current with the phase opposite to that of a current ripple component of the excitation inductor through the coupling effect of the coupling inductor unit; the filtered current is superimposed with the current ripple component to counteract the ripple of the input current. Zero input current ripples are realized while zero-voltage switching of the switching tube is realized.
Owner:CENT SOUTH UNIV

Active filter, system, chip and electronic device

An active filter, system, chip and electronic device, comprising: an input end of an RC filter module receives a to-be-filtered signal of the active filter to passively filter the to-be-filtered signal to obtain a passively filtered signal; an output end of a voltage follower module outputs a voltage following the rise and fall of the passively filtered signal to obtain a voltage following signal; a flip voltage follower module makes the filter output end output a voltage following the rise and fall of the voltage following signal to obtain an actively filtered signal; the filter output end is an output end of the active filter; a positive feedback module is connected between the filter output end and the RC filter module, and when the frequency of the to-be-filtered signal falls within a preset cutoff range, the positive feedback module is used to feed back the actively filtered signal to the RC filter module. By setting the flip voltage follower module, the output impedance of the active filter is reduced, so that the active filter can be applied to a high-frequency scene.
Owner:ZHUHAI JIELI TECH

EMI noise current counteracting circuit and air conditioning system

The embodiment of the utility model discloses an EMI noise current counteracting circuit and an air conditioning system, and relates to the field of noise reduction circuits. The circuit comprises a current detection module, a passive filtering module, a noise module and a current offset module. The three-phase input end of the current detection module is connected with the three-phase output end of a power grid, the three-phase output end of the current detection module is connected with the three-phase input end of the passive filtering module, the detection end of the current offset module is connected with the detection end of the current detection module, and the current offset module detects the current value of noise current through the current detection module. The offset currents are the same in output current value and opposite to the noise current in direction; the neutral end of the current counteracting module is connected with the neutral end of the power grid, the grounding protection end of the current counteracting module is connected with the grounding protection end of the power grid, and the current counteracting module inputs counteracting current into the EMI noise current counteracting circuit to counteract noise current.
Owner:GD MIDEA HEATING & VENTILATING EQUIP CO LTD +1

A Dynamic Control System and Method for Ultra-High Frequency Harmonics Based on Adaptive Control

This invention discloses an ultra-high frequency harmonic dynamic control system and method based on adaptive control, belonging to the field of adaptive control technology. The invention acquires ultra-high frequency harmonic signals and divides them into several independent frequency bands, obtaining the occurrence time and duration of each band to form the frequency of harmonic occurrence per unit time. The K-nearest neighbor algorithm is used to analyze this frequency, outputting frequency band classification results and assigning corresponding filtering modes to each band, then executing filtering. The frequency of occurrence per unit time for each band is updated, and the classification status change is compared with the target threshold. The operational stability of passive and active filtering is calculated, and the filtering effect deviation is further calculated. Based on both, a switching command is output. Switching to active filtering disconnects the corresponding passive branch, adjusts the active filtering parameters, and includes it in the control scope. Switching to passive filtering activates the corresponding branch, adjusts the parameters, and removes the frequency band from the active filtering range.
Owner:ZHIWANG (BEIJING) NEW ENERGY CO LTD +1

Active suppression compensation method for direct-current side ripple of power supply and circuit design

The invention discloses a power supply DC side ripple active suppression compensation method and circuit design, and the method comprises the following steps: collecting a voltage or current signal of a power supply DC side in real time, obtaining ripple characteristic parameters through band-pass filtering and peak detection, and the ripple characteristic parameters comprise the frequency, amplitude and phase of the ripple; based on the ripple characteristic parameters, synchronizing phases through a phase locked loop (PLL) and generating a compensation signal which is equal to the ripple in amplitude and opposite to the ripple in phase; the compensation signal is loaded to a direct-current side loop through an input interface, the input interface is connected with a direct-current bus or a filter capacitor in parallel to offset direct-current side ripples, accurate dynamic compensation is achieved, the ripple signals are collected in real time, frequency, amplitude and phase parameters are extracted, a phase locking ring is used for generating a reverse-phase compensation signal, and the compensation precision is improved. Compared with a traditional passive filtering scheme, the method has the advantages that the ripple suppression efficiency is remarkably improved, and the method is particularly suitable for broadband and multi-harmonic mixed scenes.
Owner:TAIYUAN YONGMING HENGDONGYUAN ELECTRONICS CO LTD +1

Method and system for double frequency voltage ripple suppression based on virtual parallel impedance

PendingCN122419175ACapacitanceTransformer
This invention discloses a method and system for suppressing second-harmonic voltage ripple in power electronic transformers based on virtual parallel impedance, aiming to solve the problem of excessive voltage ripple in submodule capacitors of common-frequency chain power electronic transformers. Without adding additional passive filtering components or active power decoupling circuits, virtual parallel impedance feedforward control is introduced into the primary-side port voltage control loop of the isolation-stage modular multi-active bridge converter to reshape the closed-loop input impedance characteristics of the port. A bandpass filter is used to extract the second-harmonic voltage component, and a virtual admittance gain is applied to make the converter port exhibit low impedance characteristics at second-harmonic frequency, thereby guiding fluctuating power to preferentially flow to the common high-frequency AC bus. The natural coupling cancellation effect of three-phase fluctuating power at the bus significantly suppresses voltage ripple on the DC capacitor. This invention requires no additional hardware, effectively reducing the demand for capacitor values ​​and improving the power density and operational reliability of the transformer system.
Owner:BEIJING JIAOTONG UNIV

Method for filtering zero-sequence harmonics of neutral line of low-voltage power distribution network by adopting zero-sequence filter

The invention provides a method for filtering high-frequency zero-sequence harmonic waves of a neutral line of a low-voltage power distribution network in a zero-sequence filter mode based on a magnetic flux compensation principle, compared with a traditional passive filter and an active filter APF, the zero-sequence filter has relatively high adaptability and practicability, but for complex working conditions in a line, the zero-sequence filter has relatively high adaptability and practicability, and the zero-sequence filter cannot be used for filtering the high-frequency zero-sequence harmonic waves of the neutral line of the low-voltage power distribution network. For example, three-phase imbalance and the like, a zero-sequence harmonic low-resistance channel is possibly formed by a filter, so that the current of a neutral line is increased. According to the utility model, the zero-blocking device is added in the line to filter the zero-sequence harmonic wave at the power supply side, so that the filtering effect is improved, the high-frequency zero-sequence harmonic wave of the neutral line is finally filtered, and the severe conditions such as burning of electric equipment and disconnection of the neutral line can be prevented.
Owner:HANGZHOU E ENERGY ELECTRIC POWER TECH CO LTD

Multi-channel analog signal output module

The invention relates to a multi-channel analog signal output module. The multi-channel analog signal output module comprises a main control module, a current output module and a communication multiplexing module, the communication multiplexing module comprises an isolation transmission unit, a modulation-demodulation circuit and a multiplexing switch unit. The multiplexing switch unit is connected with the modulation-demodulation circuit and an output loop of the current output module through a common bus and a plurality of coupling branches; each coupling branch comprises a gating switch assembly and a passive filtering assembly which are connected in series. The gating switch assembly is controlled to be switched on, and the passive filtering assembly is configured to block the analog current signal and allow the frequency shift keying analog signal to pass through. Through a serial connection structure of the gating switch and the filtering assembly, multiplexing of a single modulation-demodulation circuit on multi-path output is realized, hardware cost is reduced, meanwhile, direct-current high voltage is effectively blocked, switching interference is inhibited, and communication stability and module reliability are improved.
Owner:SHANGHAI AUTOMATION INSTRAION CO LTD

Unmanned aerial vehicle measurement and control signal detection method in complex network environment

The invention discloses a method for detecting measurement and control signals of an unmanned aerial vehicle in a complex network environment. The method comprises the following steps: step 1, multi-dimensional joint perception and signal representation; the method has the beneficial effects that a dual enhancement mechanism of separation and reinforcement learning dynamic anti-interference guided by physical characteristics is introduced, and normal form transformation from passive filtering to intelligent countermeasure is carried out, so that inherent robustness is improved through physical characteristic constraint on a kernel (separation algorithm); active and strategic anti-interference is realized on the periphery through reinforcement learning, and a deep defense system is formed; meanwhile, a mixed framework with unsupervised clustering pre-screening and physical feature guiding ICA as a main mode and light weight fine tuning as an auxiliary mode is adopted, fusion innovation from data driving to physical knowledge guiding and light weight intelligence is achieved, the core separation process depends on physical attributes and unsupervised learning of signals, and dependence on a large amount of labeled data is greatly reduced.
Owner:TIANJIN ZHONGHENG DIXIN TECH CO LTD

Defence apparatus and method against physical backdoor attacks on biometric identification systems

The application provides a defense device and method for a physical backdoor attack on a biological information recognition system, and belongs to the field of information security. The biological information recognition system is used for collecting multi-modal biological signals and authentication. The defense device comprises: a coupling path blocking module: from active shielding, passive filtering and voltage stabilization, the conduction of malicious noise in the physical connection path is cut off or weakened, and the stability of the front-end physical environment is ensured. A physical domain signal purification module: from real-time monitoring of signals, feature analysis to interference suppression, a closed loop is formed, and the noise transmitted from the power supply circuit to the collection device is reduced. A digital domain semantic verification module: verifies the collected multi-modal biological signals, and judges whether there are abnormal or backdoor injection attack signs. A system control and management module: realizes communication between external devices and each module, and makes decisions according to the digital domain semantic verification result. The application can effectively block the physical interference signals used for injecting backdoors, and ensure the safety and reliability of the biological information recognition system.
Owner:ZHEJIANG UNIV

Universal EMC automatic diagnosis rectification system

The invention relates to a general EMC automatic diagnosis and rectification system. The general EMC automatic diagnosis and rectification system comprises a passive filter network and a band switch connected with the passive filter network, the signal acquisition module is connected with the adjustable passive filtering module; the judgment module is connected with the signal acquisition module and is internally provided with an AI learning type rule base; and the parameter adjusting module is connected with the judgment module and the band switch. The signal acquisition module performs spectral analysis on the EMI filtering signal, the judgment module performs EDA co-simulation based on an AI learning type rule base on spectral characteristics to determine a rectification driving signal, and the parameter adjustment module generates mechanical driving force according to the rectification driving signal to control open circuit and short circuit of the band switch. Therefore, the capacitance value, the inductance value and the resistance value of the passive filter network are adjusted. The problems that existing EMC rectification depends on a test site and manpower, efficiency is low, and accuracy is poor are solved. According to the method, the AI learning type rule base is added, deep learning is carried out through historical rectification cases, and the overall effect is improved.
Owner:北京航天微电科技有限公司

Non-isolated unidirectional boost converter and coupled inductor design method thereof

The application provides a non-isolated one-way Boost converter and a coupled inductor design method thereof. The converter comprises a coupled inductor unit, a primary winding of the coupled inductor unit serving as an excitation inductor of the converter, and a secondary winding of the coupled inductor unit being connected in series with an auxiliary capacitor to form a passive filter branch. The passive filter branch is connected in parallel with an input power supply. The converter is configured to realize zero-voltage turn-on of the first switch tube or the second switch tube by controlling the alternating on-off of the first switch tube and the second switch tube, so that the current flowing through the excitation inductor flows bidirectionally. The passive filter branch is configured to generate a filter current with a phase opposite to a current ripple component of the excitation inductor through the coupling effect of the coupled inductor unit. The filter current and the current ripple component are superposed to offset the ripple of the input current. The application realizes zero-voltage turn-on of the switch tube and zero input current ripple at the same time.
Owner:CENT SOUTH UNIV