61 results about "Electromagnetic interference control" patented technology

The invention discloses a controller area network (CAN) bus-based anti-electromagnetic interference method and a CAN bus-based anti-electromagnetic interference device, which belong to the technical field of battery electric vehicle buses. Each control unit of a battery electric vehicle shares all information and resources by a CAN bus so as to fulfill the aims of simplifying wiring, reducing the number of sensors, avoiding the repetition of control functions, improving the reliability and maintainability of a system, reducing the cost and better matching and coordinating each control system. The key for well control over the battery electric vehicle is the reliability of CAN bus communication. The battery electric vehicle is a high-mechatronics product, and the whole system may generate a great number of high frequency signals when working to influence the normal communication of the CAN bus. The method and the device aim to improve the anti-interference capability of the CAN bus; and an anti-interference circuit is designed by utilizing the principle of CAN bus transmission, and a common mode choke is arranged to filter common mode electromagnetic interference on a signal wire and suppress the external transmission of own electromagnetic interference so as to greatly improve the reliability of the CAN bus communication.

The invention belongs to the field of estimation and protection of electromagnetic interference in communication engineering, and particularly relates to a method for estimating the crosstalk magnitude, caused by electromagnetic interference of an external transient state, of a PCB microstrip transmission line, wherein the method is for estimating the size of transient state response of a PCB which works normally when the PCB is interfered by external sudden electromagnetic pulses in study of the integrity of PCB microstrip line signals under complex electromagnetic environments in space. The method comprises the steps that a coupling model between a PCB microstrip line and transient state electromagnetic interference in the air is established; the coupling between the PCB microstrip line and the transient state electromagnetic interference in the air is calculated according to the coupling model between the PCB microstrip line and the transient state electromagnetic interference in the air; coupling voltages are added to the microstrip transmission line, and discretization is carried out on a transmission line equation by utilizing an FDTD method; simulation is carried out on a crosstalk equation after discretization by utilizing Matlab, and a crosstalk result is obtained. According to the method for estimating the crosstalk magnitude, caused by the electromagnetic interference of the external transient state, of the PCB microstrip transmission line, the crosstalk of spacial electromagnetic interference on the PCB microstrip line is calculated through a simple method, calculation amount is reduced, and efficiency is improved.

The invention provides a method for removing an electromagnetic interference (EMI) signal by a coal mine underground transient electromagnetic instrument background field guidance frequency-selecting technology; a coal mine underground transient electromagnetic instrument adopted in the method comprises a receiver consisting of a central processing unit (CPU), a memory, an analog/ digital converter (ADC), a receiving circuit and a receiving coil, and a transmitter consisting of a transmission circuit and a transmitting coil; and the receiver is connected with the transmitter by a communication cable for realizing synchronous control. According to the method, a spectrum analysis method is firstly used for analyzing the frequency of the maximum amplitude of the EMI signal of the background field, and then the frequency transmitted by the transient electromagnetic instrument is guided according to the measured frequency of the maximum amplitude of the EMI signal of the background field, so that the EMI can be rapidly and accurately eliminated, accurate observed value of the secondary field can be obtained, and the aim of accurately eliminating the EMI signal can be achieved.

An embodiment of the present application discloses an electromagnetic interference control method and a related device. The electronic device comprises a display screen and an under-screen fingerprintmodule arranged in a preset area of the display screen. The method comprises: detecting whether an electromagnetic interference occurs between the under-screen fingerprint module and the display screen when the under-screen fingerprint module is detected to be in a startup state, and the preset area of the display screen is in a lighted state; a frequency hopping switching operation is performedfor a display screen mobile industry processor interface MIPI when an electromagnetic interference between an under-screen fingerprint module and the display screen is detected. The present application facilitates accuracy and stability of off-screen fingerprint unlocking by an electronic device.

Embodiments of the application disclose a method for controlling electromagnetic interference, and related products. The method comprises the following steps: when an electronic device turns on the camera, acquiring a first MIPI (mobile industry processor interface) working frequency of an MIPI of the camera, acquiring a second MIPI working frequency of an MIPI of a display screen, determining whether the first MIPI working frequency is interfered or not according to the second MIPI working frequency, acquiring a frame rate and a resolution of the display screen if yes, determining a third MIPI working frequency generating less interference to the first MIPI working frequency than the second MIPI operating frequency according to the frame rate and the resolution, and adjusting the MIPI working frequency of the display screen according to the third MIPI working frequency. In this way, the MIPI working frequency of the display screen can be dynamically adjusted without changing the hardware design of the electronic device, so that the MIPI of the display screen works in a working frequency with less interference to the MIPI of the camera, which eliminates or reduces the interferencewith camera communication, improves the transmission efficiency of captured images, and achieves a better shooting experience.

The embodiment of the invention discloses an electromagnetic interference control method and a related device, and the method comprises the steps: detecting whether electromagnetic interference occursbetween a camera and a radio frequency system when detecting that the camera of electronic equipment is in an on state; If yes, detecting a screen state of the electronic equipment, and determining adynamic switching strategy of the four antennas according to the screen state; And detecting the communication quality of at least one antenna except the currently enabled antenna according to the dynamic switching strategy, and executing an antenna switching operation to avoid or reduce the electromagnetic interference when the communication quality meets the switching condition. The embodimentof the invention is beneficial to reducing or avoiding electromagnetic interference.

Embodiments of the application disclose a method for controlling electromagnetic interference and related devices. The method comprises the following steps: starting a wireless high-fidelity Wi-Fi module when detecting a screen projection request for target screen projection equipment; searching for and accessing a target wireless network, which is connected with the target screen projection equipment; detecting whether the Wi-Fi module and the display mobile industry processor interface MIPI have electromagnetic interference; when detecting electromagnetic interference, outputting first prompt information, extinguishing the display screen, and performing the screen projection operation, wherein the first prompt information is used to indicate that the electronic equipment is performing the screen-out projection operation. The application is useful for avoiding the electromagnetic interference between the Wi-Fi module and the display mobile industry interface MIPI, thereby improving the stability of communication in a screen projection scenario.

The invention belongs to the technical field of sensor switches and discloses a light control switch composition based on a mechanoluminescence material. The light control switch composition is composed of mechanoluminescence composite materials, photoresistors and control circuits. The mechanoluminescence composite materials transmit light under the effect of dynamic external force. The photoresistors are connected with the control circuits through lead wires and receive the light of the mechanoluminescence, thereby resulting in resistance change. When changed resistance values reach reference values preset by the control circuits, switch functions are realized. The switches comprise embedded type and an un-embedded type. According to the embedded type light control switch, the photoresistor is directly embedded into the mechanoluminescence composite material. The photoresistor and the mechanoluminescence composite material of the un-embedded type light control switch are connected through a light guide medium. According to the light control switch composition, the light control switches are independent of a natural light source and a traditional artificial light source, the application market of the light control switches is expanded, and the light control switches have wide application prospect in aspects such as building environment safety monitoring, earthquake early warning and electromagnetic interference-free control circuits.

The embodiments of the invention disclose electromagnetic interference control methods and a related device. A method comprises the steps of detecting whether electromagnetic interference occurs between a radio frequency system and a display screen of electronic equipment or not when it is detected that the electronic equipment is in a preset scene, wherein the preset scene comprises a bright screen scene; and carrying out frequency hopping switching operation for a display screen mobile industry processor interface (MIPI) when it is detected that the electromagnetic interference occurs in theelectronic equipment. According to the method and the device, communication stability in the bright screen scene can be improved.

The invention provides a novel frequency jitter wave trough breakover control system. The system has a wave trough breakover function and also has a frequency jitter function in a full input voltage range and a full load range. The energy of the electromagnetic interferences is dispersed in the frequency bands in a whole frequency jitter range; therefore the influence resulted from the electromagnetic interferences is controlled to the lowest level; the integral performance of the controller is improved; circuit multiplexing can be carried out through the control of the two techniques; a large portion of wafers can be saved; and the application rate is improved.

The invention relates to the field of electronic communication, in particular to a passive optical network multi-user unit radiation emission positioning rectification method. The method comprises thefollowing steps: diagnosing a source and a propagation path of interference; performing the safe grounding and lap joint of EMC in advance; removing unneeded frequency components from a frequency domain through filtering, thereby reducing the electromagnetic interference from the aspects of conduction and radiation; inhibiting various types of electromagnetic interferences propagated spatially byshielding; replacing a suspicious element with an element meeting the EMC requirement; reducing the output energy of the crystal oscillator and harmonic waves of the crystal oscillator for a crystaloscillator product through a method of connecting resistors in series or connecting resistors in parallel. Starting from the source, the method reduces the radiation energy, destroys or changes the path of radiation interference from the source, reduces the gaps, enhances the filtering, changes the position of a line to destroy the radiation mechanism, and can achieve the quick and accurate passive optical network multi-user unit radiation emission positioning rectification.

The invention relates to the field of motor manufacturing, in particular to an anti-electromagnetic interference control servo-actuator. The servo-actuator is characterized in that on the basis of the prior control servo motor structure, the outside of a servo-actuator shell (4) is coated with one or a plurality of outer shielding covers (3); the whole machine core is arranged inside a large shell consisting of a front cover (1) and a rear shielding cover (2); the front cover (1) is made of metal and forms a shielding layer with the rear shielding cover (2); and a stator is formed by assembling a shielding magnetic shoe sleeve (5) and a magnetic shoe (6). The anti-electromagnetic interference control servo motor strengthens shielding on the whole and further improves the capacity for controlling anti-electromagnetic interference of the servo-actuator, thereby putting an end to failure phenomenon of a currency counting machine or a currency detector and further improving the currency counting precision of the currency counting machine.

The invention discloses a system and a method for reducing electromagnetic interference of equipment based on a pulse modulation circuit. The system comprises strong current equipment, electromagneticradiation monitoring equipment, a pulse modulation circuit and a linear motor; the strong current equipment generates electromagnetic radiation; the electromagnetic radiation monitoring equipment isused for monitoring the electromagnetic radiation generated by the strong current equipment so as to obtain first electromagnetic radiation quantity; the first electromagnetic radiation quantity is compared with a radiation quantity threshold value; and the pulse modulation circuit is used for controlling the linear motor through the pulse modulation circuit when the first electromagnetic radiation quantity is equal to the radiation quantity threshold value. According to the system, the linear motor is driven by the driving mode of the pulse width modulation circuit, so that the problem of internal interference of strong current to weak current is solved.

The invention relates to an electromagnetic interference control method, which comprises the steps of obtaining a current communication channel of electronic equipment when the electronic equipment is in a screen-on state; and when it is detected that the driving frequency of the display screen interferes with the current communication channel of the electronic device, adjusting operation is executed for the driving frequency of the display screen, and the adjusting operation is frequency hopping or spectrum spreading. The invention also discloses an electromagnetic interference control device, electronic equipment and a computer readable storage medium. The driving frequency of the display screen is enabled to avoid the current communication channel of the electronic equipment, and the influence of the driving frequency of the display screen on the communication quality of the electronic equipment is avoided.

Embodiments of the invention disclose an electromagnetic interference control method and a related product. The method comprises when electronic equipment is in a payment scene, obtaining the first sampling frequency of a biological recognition sensor, obtaining the first MIPI working frequency of a display screen MIPI, determining whether the first sampling frequency is interfered according to the first MIPI working frequency, if yes, determining the second sampling frequency, without being interfered by the first MIPI working frequency, of the biological recognition sensor, and adjusting thesampling frequency of the biological recognition sensor to be second sampling frequency, so that the sampling frequency of the biological recognition sensor can be adjusted dynamically when the electronic equipment is in the payment scene under the condition of without changing the hardware design of the electronic equipment, the electromagnetic interference of the working frequency of the display screen MIPI on the biological recognition sensor is eliminated or reduced, and the accuracy of identification is guaranteed, so that preferable user payment experience is realized.

The invention discloses a multi-core anti-electromagnetic interference control cable, which belongs to an anti-electromagnetic interference control cable and mainly solves the technical problems that the conventional cable has poor anti-electromagnetic interference performance, is easily disturbed by an electromagnetic field and the like. The technical scheme of the invention has the key points that: more than one layer of cable core consisting of more than three anti-electromagnetic wires is arranged around the anti-electromagnetic wires 1 by using a single-core anti-electromagnetic wire as a center; and the outer layer of the cable core is provided with an aluminum-plastic composite film lapped shielding layer, a tinned copper wire woven shielding layer and an environment-friendly low-smoke halogen-free flame-retardant polyolefin elastomer jacket in turn from the inside to the outside. The cable has the functions of anti-electromagnetic interference, environmental protection, flame resistance, abrasion resistance, water prevention, weather resistance, ageing resistance, mould resistance and the like, and can meet the requirement of synchronous transmission of power and signals under a strong magnetic field environment, particularly meet the requirement of a large-sized power plant or a large-sized data switching system and also meet the using requirements of ships and rapid trains for reliability, long service life, small volume and light weight.

Embodiments of the invention disclose an electromagnetic interference control method and a related device. The method comprises the following steps of acquiring a frequency data packet of a Bluetoothmodule; determining that the Bluetooth module and a display screen generate electromagnetic interference according to the frequency data packet, and carrying out data transmission with Bluetooth equipment by the Bluetooth module through using a first Bluetooth channel; and switching the first Bluetooth channel to a second Bluetooth channel so as to reduce or avoid the electromagnetic interference,and sending a first message to the Bluetooth equipment, wherein the first message comprises the second Bluetooth channel. According to the electromagnetic interference control method and the relateddevice, the electromagnetic interference between the Bluetooth module and the display screen can be reduced or avoided.

The invention discloses a method for locating EMI (electromagnetic Interference) noise of a switch power supply rapidly. The method comprises the following steps of: firstly, performing conduction test on the switch power supply according to a standard EMI testing method and then locating the EMI noise for a frequency point beyond a standard limiting value; establishing a differential mode noise filter network by using a differential mode capacitor and a differential mode choking coil, and establishing a common-mode noise filter network by using a common-mode capacitor and a common-mode choking coil; connecting the differential mode filter network and the common-mode filter network on a filtering carrier plate in parallel, controlling the effectiveness of the differential mode filter network and the common-mode filter network by using a switch, connecting the filtering carrier plate in series at the input end of the switch power supply, and verifying whether the noise frequency band beyond the standard is common-mode interference or differential-mode interference. Compared with the prior art, the method for locating the EMI noise of the switch power supply rapidly has the characteristics of being rational in design, convenient to operate and the like, efficiently guarantees normal work of electronic devices around, enables a communication system to transmit data completely and exactly, and reduces occurrence of abnormal conditions of the system such as halt and alarm.