73results about How to "Improve signal anti-interference ability" patented technology

The invention discloses a tunnel water leakage hidden disease detection device. The tunnel water leakage hidden disease detection device comprises a cab, a power system, a circumferential detection system and a data acquisition system; the circumferential detection system is arranged on a power box and comprises a front detection arm, a middle detection arm, a rear detection arm and a moving system in sequence; each of the front detection arm, the middle detection arm and the rear detection arm comprises a telescopic frame; an circumferential arc-shaped rail is arranged on each telescopic frame; and a data acquisition system is arranged on each circumferential arc-shaped rail. According to the tunnel water leakage hidden disease detection device, hidden diseases such as cavities, cracks, accumulated water and the like hidden in primary supports and secondary linings can be detected, so that the position and cause of water leakage of a tunnel can be found fundamentally. Meanwhile, the detection precision is high, and the anti-interference capability of signals is strong.

The invention discloses a voltage detection circuit of a motor controller for an electric vehicle. The voltage detection circuit comprises a voltage input circuit, an input differential operation circuits, an analog opto-coupler isolation circuit, a voltage follower and a DSP (Digital Signal Processing) processor, wherein an output end of the voltage input circuit is connected with an input end of the input differential operation circuit, and an output end of the input differential operation circuit is connected with an input end of the analog opto-coupler isolation circuit; and an output end of the analog opto-coupler isolation circuit is connected with an input end of the voltage follower, and an output end of the voltage follower is connected with a detection port of the DSP. According to the voltage detection circuit, the cost is saved, simultaneously the voltage value of a power supply of the motor controller can be monitored in real time by hardware, and the supply voltage parameters of the controller can be supplied to a motor control system of a pure electric vehicle.

The invention relates to an image processing system based on a Field Programmable Gate Array (FPGA), and belongs to the field of image processing. The system includes: a video decoding module, an image processing module arranged on the FPGA and a video coding module, wherein the video decoding module includes a LVDS receiving unit, a CCIR-D receiving unit and a SD-SDI receiving unit, and the video coding module includes a DVI coding module and a CCIR-D coding module. According to the invention, the SD-SDI receiving unit adopts an equalizer GS2994, and a clock recovery device GS2965 for strengthening the signal anti-interruption capacity, and adopts a SDRAM sequential to realize conversion of a PAL sequential and a VGA sequential; the chip clock of the SDRAM can meet the requirements of the design at 100 MHZ. The image processing system has small power consumption. The image processing system and the FPGA require no need of occupation of exclusive pins therebetween. The image processing system addresses the problem of complexity of debugging of image processing based on FPGA in the prior art.

The invention discloses a tower crane lifting hook video monitoring device with energy-saving and doubling functions, which comprises an image collecting and transmitting module, a solar power supply module and a display memory module, wherein the image collecting and transmitting module and the solar power supply module are arranged on an amplitude-change trolley of a tower crane, the display memory module is arranged in a cab, the image collecting and transmitting module comprises an infrared all-in-one machine, a video sever and a wireless network bridge which are sequentially connected, the infrared all-in-one machine and the video server are simultaneously connected with a dormancy energy-saving controller, the solar power supply module comprises a power supply controller which is respectively connected with a solar assembly and a storage battery, the power supply controller is respectively connected with the infrared all-in-one machine, the video server, the wireless network bridge and the dormancy energy-saving controller, the display memory module comprises a multiplying power control module, an image control display and a wireless network bridge B, and the multiplying power control module is connected with a pedal unit. The invention also discloses a lifting video monitoring method using the tower crane lifting hook video monitoring device, and the remote control on the camera lens magnification and the dormancy and energy-saving functions are realized through a pedal module.

The invention discloses a power equipment and transmission line malfunction comprehensive online monitoring system which comprises a wireless temperature measuring terminal, a line malfunction detector, a transfer station, an information receiving main station, a database server and a monitoring host. The wireless temperature measuring terminal is wirelessly connected with the information receiving main station through a built-in wireless communication module, the line malfunction detector is wirelessly connected with the information receiving main station through a built-in wireless communication module and the transfer station, and the information receiving main station is connected with the database server which is connected with the monitoring host. The system can monitor and upload power equipment temperature rise standard exceeding and transmission line ground fault information in real time, quickly locate line fault sections and fault branches, shorten fault clearing time and improve safety and reliability of power equipment and transmission lines.

The invention discloses a method for achieving frequency modulation emergency broadcast based on RDS. The method comprises the following steps that firstly, basic tuning and switching information frames, emergency broadcast data frames and broadcast text frames are combined into a data package to be sent out at regular intervals through the emitting station; secondly, when a receiving terminal receives the data package sent by the emitting station, whether the emitting station supports emergency broadcast and plays the emergency broadcast or not is recognized according to the basic tuning and switching information frames, if the emitting station supports the emergency broadcast and plays the emergency broadcast, the third step is carried out, and otherwise, the next data package is waited to be received and processed; thirdly, when the receiving terminal judges that the receiving terminal is a matched receiving terminal according to the emergency data frames, the emergency broadcast is received and played. The frequency modulation emergency broadcast data information is transmitted based on the RDS technology, the frequency resources are saved, the anti-interference ability of the signal is strong, and users can receive the emergency broadcast information in time.

The invention discloses a modified real-time emotion recognition method and system based on eye movement data, and the method comprises the steps: collecting the eye movement data in a VR environmentin real time, and carrying out the prediction of a fixation point through the eye movement data; obtaining a preliminary emotional state through the panorama of the current frame and the predicted fixation point region map of the next frame; and correcting the initial emotional state in combination with historical eye movement data to obtain a final emotional state at the current moment. The system can predict the emotion of the user in real time and improve the experience of the user in the VR environment.

The invention discloses a water meter centralized-reading device in a master-slave machine mode. The device comprises a GPRS module, master machines consisting of a primary master machine and a secondary master machine, slave machines, a collector and a terminal water meter, wherein the master machines comprises the primary master machine and the secondary master machine, the master machine are divided into at most three levels, at most 64 slave machines are networked, the master machines and the slave machines are connected in a wireless transmission mode, the plurality of slave machines can be arranged on each master machine, the GPRS module is connected with the master machines via 485 buses in a wired manner, the slave machines are connected with the collector via the 485 buses in a wired manner, the collector and the terminal water meter transmit data via MBUS, each master machine corresponds to an ID number, and at most 16 slave machines can be networked by the single master machine, the ID numbers of the slave machines and the corresponding master machine are the same, and each master machine is provided with a clock for periodically automatically reading the meter and uploading data.

The embodiment of the invention provides a VoLTE voice quality improvement method and device for TD-LTE. In the method, network side equipment (such as a base station) can carry out secondary order selection on the MCS after the MCS and the TBS are preliminarily determined according to the CQI; the TBS which can bear the VoLTE voice packet to be sent and can reduce the order of the MCS can be selected under the condition that the number of RBs is kept unchanged (namely, the capacity of an air interface is kept unchanged); therefore, the purpose of MCS order reduction is achieved while normal transceiving of data is ensured, the signal anti-interference capability of a data packet is improved, and the VOLTE voice quality is improved.

The invention provides an automatic guiding vehicle intelligent control system and method. The system comprises a trolley charging station and a plurality of automatic guiding vehicles. Signal connection is established among the plurality of automatic guiding vehicles through a wireless mesh network, and the plurality of guiding vehicles include a first automatic guiding vehicle that performs a delivery task and idle automatic guiding vehicles that are fully charged. When the current electric quantity of the first automatic guiding vehicle is lower than a preset electric quantity, the first automatic guiding vehicle sends an alert signal to a main control device and a nearby idle automatic guiding vehicle through the wireless mesh network, and the idle automatic guiding vehicle obtains theinformation of the delivery task and a target of the delivery task from the first automatic guiding vehicle through connection to continue to complete the delivery task The system and method of the invention realize stronger signal anti-interference capability, and are more efficient in vehicle replacing management and control.

The invention, which belongs to the technical field of data acquisition, particularly relates to a data acquisition system and method based on a CAN bus and wireless communication. The system comprises a data acquisition unit and a mobile terminal; and the data acquisition unit is connected with the mobile terminal. The data acquisition unit consists of a microprocessor, a switching unit connectedwith the microprocessor and a wireless communication unit connected with the microprocessor. The data acquisition unit is used for acquiring external CAN bus data, encoding the collected data, and transmitting the encoded data to the mobile terminal wirelessly; and the mobile terminal is used for displaying the received data, analyzing the displayed data and storing the analyzed data. Therefore,problems that traditional wired CAN data collection is inconvenient, and a mobile terminal is troublesome to maintain are solved; CAN data collection is conducted in a wireless mode instead of a traditional wired mode; and a problem that the mobile terminal analyzes data is solved in a DBC loading mode.

The invention discloses a device and a method for recording through earphone microphone jack expansion. The device is provided with an earphone microphone plug and a circuit, and the earphone microphone plug is used for being accessed in an earphone microphone jack; the circuit is used for being connected with the earphone microphone plug, and four joints of the earphone microphone are connected into the earphone microphone jack and are used for expanding sound transmission on the basis of the circuit. The method comprises the following steps: S1, introducing a sound channel signal; S2, carrying out voltage dividing and sound mixing on the introduced sound channel signal; S3, carrying out level signal matching and attenuation on the signal after voltage dividing and sound mixing; and S4, introducing a sound frequency signal after matching and attenuation into the input end of a microphone to reach recording and sound transmission. The problems of low antijamming capability and large noise when system sound is captured by using a traditional recording manner are solved, and application software and program for sound capture, transmission and recording can be helped to capture high-quality sound signals from the microphone by using the device and the method.

The invention discloses a ground-based broadcasting type locating method. Ground-based broadcasting stations are built in a located area, code division multiple access modulation is carried out on information of identification codes, the longitude, the latitude, the elevation and the clock of the ground-based broadcasting stations, the ground-based broadcasting stations continuously send the processed information of the identification codes, the longitude, the latitude, the elevation and the clock of the ground-based broadcasting stations, the information is transmitted to an onboard receiver of an aircraft through an L band, and the onboard receiver receives the information sent by the ground-based broadcasting stations, and carries out frequency conversion and demodulation on the information to obtain the identification codes, the longitude, the latitude and the clock, wherein the identification codes, the longitude, the latitude and the clock are contained in the information sent by the ground-based broadcasting stations; comparison between the signal receiving moment of the onboard receiver and the information, obtained through demodulation, of the clock is carried out, the distance between the aircraft and the corresponding ground-based broadcasting station is calculated, and then the position of the aircraft is obtained through calculation. According to the ground-based broadcasting type locating method, anti-interference performance of signals is good, accurate locating and accurate navigation of the aircraft can be achieved, and the ground-based broadcasting type locating method has the advantages of being all-weather, high in accuracy, low in cost, easy to achieve, good in real-time performance, multipurpose and the like.

The invention discloses a water-bottom high-voltage direct current transmission system based on carrier energy extraction and feedback. The system mainly comprises a direct current power transmissioncircuit, an auxiliary carrier power circuit and a carrier voltage signal feedback circuit. The direct current power transmission circuit performs transmission of electric energy from a water surface to a water bottom, the auxiliary carrier power circuit performs power assistance in the circuit at the water bottom, and the carrier voltage signal feedback circuit feeds back the output voltage at thewater bottom to a water source. The water-bottom high-voltage direct current transmission system achieves that the water bottom source separately assists in power supply and direct closed-loop control from the output voltage to the water source, and is good in timeliness, simple in starting process and high in reliability.

The invention discloses an automatic detecting device for wrong hooks of a special gondola, which comprises a detecting element and a PLC (programmable logic controller). The detecting element consists of a SE1 and a SE2 which are mounted beside a road bed by supports, the distance between the ranging detecting devices SE1 and SE2 can be adjusted, and the ranging detecting devices SE1 and SE2 are connected with the PLC, and are ranging sensors. A detecting method includes that measuring distances among the ranging sensors, the detected gondola, detected air ducts and the ground by the ranging sensors, and judging whether hooks of the special gondola are correctly connected or not. The hooks of the special gondola are correctly connected if an air duct is detected between two carriages by twice or the air duct cannot be detected between the two carriages, the dumping hooks of the special gondola are incorrectly connected if the air duct is detected between the two carriages once, and the automatic detecting device alarms so that the gondola stops to remove failures.

The invention belongs to the technical field of high-precision time delay, and particularly relates to a high-precision time delay system and method based on an FPGA and a time delay chip, and the system comprises an external triggering input module, an FPGA module, a low-jitter clock module, a fine time delay generation module, and an ultra-narrow pulse width signal generation module. The external triggering input module is connected with an I / O port of the FPGA module. The FPGA module is connected with a low-jitter clock module, the low-jitter clock module U3 provides a low-jitter clock signal for the FPGA module, the FPGA module is connected with the fine delay generation module, and the fine delay generation module is connected to the ultra-narrow pulse width signal generation module.Coarse time delay is achieved through counting of the FPGA module, and the time delay range is large; the fine time delay generation module can realize fine time delay through a special time delay chip, and the time delay resolution is high and can reach a time delay range of 5 ps to 5.115 ns; and the low-jitter clock module is adopted to generate low-jitter clock signals, and low-jitter and high-quality reference clock signals are provided for the FPGA. The system and the method are used for signal delay.

The invention discloses an electric power Internet of things infrared knife switch temperature measurement method and device. The method comprises the following steps that temperature data of a knifeswitch is collected through an infrared temperature sensor and the temperature data is sent to a monitoring terminal; a monitoring terminal receives an issued instruction by using the data acquired byan infrared temperature sensor, and regularly reports the encrypted data to a LoRa gateway through an AES encryption algorithm; the LoRa gateway receives the encrypted data reported by the monitoringterminal and stores the encrypted data in a network server; and a cloud platform obtains the latest encrypted data from the network server at set intervals and decrypts the latest encrypted data, andcompares the decrypted temperature data with a preset temperature alarm threshold to perform corresponding safety early warning or alarm prompt according to a comparison result. In the invention, safety of temperature data detection and transmission is ensured.

The invention discloses a monitoring system for a marine exhaust gas modular desulfurization device. The monitoring system comprises a main control cabinet, a pump monitoring module, a washing tower monitoring module, an alkali supply monitoring module, a water treatment monitoring module and an HMI control module, and TCP / IP protocol communication transmission is performed between the main control cabinet and the monitoring signals of the pump monitoring module, the washing tower monitoring module, the alkali supply monitoring module and the water treatment monitoring module; the HMI controlmodule is in signal connection with the main control cabinet signal through bus communication; and the main control cabinet transmits action instruction signals to the pump monitoring module, the washing tower monitoring module, the alkali supply monitoring module and the water treatment monitoring module to realize modular matching and logic control in order to realize the execution and monitoring in an open, closed or hybrid desulfurization mode. The modular design and installation of a monitoring network structure for the ship exhaust gas desulfurization device and the system are realized by bus signal transmission and modular monitoring in order to achieve rapid design of the device and the efficient operation of integration, installation and debugging of the system.

The invention relates to the field of welding, and discloses a magneto-electricity induction-type welding line tracking device, aiming at providing a welding line tracking device which reflects the position variation of a welding line accurately. The magneto-electricity induction-type welding line tracking device comprises a detection part, an induction part and a micro processor, which are sequentially connected. The magneto-electricity induction-type welding line tracking device provided by the invention is high in tracking accuracy, low in distortion degree and high in signal anti-interference capability according to a magneto-electricity induction principle, can set a tracking mode to track the welding line automatically, and timely rectify the position deviation of a welding gun relatively to the welding line so as to guarantee that the welding gun is aligned at the welding line for performing uninterrupted automatic welding operation, improve the welding productive efficiency, and lower the welding production cost.

The invention discloses a hydraulic machinery cavitation and gas-liquid two-phase flow monitoring method and device, and particularly relates to a method and a device by the aid of active ultrasonic technology, digital signal demodulation technology and non-contact measurement technology supporting vector machine identification technology. The method includes the steps: placing an ultrasonic transducer; building a flow-state classifier; acquiring data; analyzing and identifying the data and the like. The device comprises the ultrasonic transducer, an acoustic acquisition card, a computer, a signal acquisition system, a signal analysis system and the like. The method and the device have the advantages that disassembly is convenient, interference of non-intervention installation to system operations is less, the anti-jamming capability of signals is high, flow states are accurately judged and the like. The method and the device can be applied to real-time monitoring of operation states of hydraulic machinery.

The invention discloses a steaming basket type tea baking machine. The steaming basket type tea baking machine comprises a base (1) and a tea baking cage (2), wherein the tea baking cage (2) is located at the upper end of the base (1). The steaming basket type tea baking machine is characterized in that the tea baking cage (2) adopts a steaming basket type structure; a tea baking plate (3) is arranged in the tea baking cage (2); fine holes are formed in the tea baking plate (3); a bamboo woven top cover (4) is arranged at the upper end of the tea baking cage (2); a heating element (5) is arranged in the base (1); a cooling plate (6) is arranged at the upper end of the heating element (5); a temperature control device (7) is arranged outside the base (1); a power regulator (8) is arranged on the side wall of the base (1); a radiator fan (9) is arranged at the lower end of the heating element (5); and a time control device (10) is also arranged in the base. The steaming basket type tea baking machine disclosed by the invention has the beneficial effects that the baking effect of tea leaves can be improved, energy resources can be saved, and the steaming basket type tea baking machineis suitable for household, can be intelligently controlled in a long-distance manner, and is convenient to use.

The invention provides an arc-shaped hermetic sealing differential electrical connector with elastic contacts, belonging to the technical filed of electric connectors. The electrical connector is composed of a plug and a socket, the plug includes a plurality of elastic contacts, a plug base, and a plug housing, the plug housing is arc-shaped, the plug base is filled inside the plug housing, the plurality of elastic contacts are fixedly arranged in the plug base via casting glue, the socket includes a plurality of contact contact members, a socket base, and a socket housing, the socket housing is matched with the plug housing in shape and is in plug connection with the plug housing, the socket base is filled inside the plug housing, and the plurality of contact contact members are fixedly arranged on the socket base, are corresponding to the elastic contacts in the socket base one by one, and are in plug connection with the elastic contacts. The differential connector is arc-shaped and is suitable to be arranged on the circular end face, the high density and small size can be realized, and the arrangement of the contacts have the anti-interference function.

The invention discloses a DC voltage type PLC photovoltaic shutoff device circuit, which includes a photovoltaic module VPV, an input capacitor C4, a switch tube Q1, a freewheel diode D1, a first LC notch filter, an output capacitor C5, a transformer T1, a coupling capacitor C6, a third LC notch filter, a signal filter resistor R1, a signal filter capacitor C7 and a second LC notch filter. The twoends of the output capacitor C5 are output terminals. When the switch tube Q1 is opened, a series current and a PLC signal pass through the freewheel diode D1 to realize normal power line carrier communication; and when the switch tube Q1 is closed, power line carrier communication is stopped, and a series current passes through the switch tube Q1, without affecting the efficiency of the system and the stability of the system. The efficiency of the system, the stability of the system and the reliability of communication can be improved.

The invention discloses an information transmission system for a railway section. The system comprises section equipment, onboard equipment and in-station equipment, wherein the section equipment contacts with the onboard equipment in a wireless way, and contacts with the in-station equipment in a wired or wireless way; the section equipment, the onboard equipment and the in-station equipment form closed loop control over a locomotive signal; the section equipment comprises a master control unit, a master control unit backup, a section radio frequency splitter, a power divider, a plurality of base station antennae and beacon antennae; the section radio frequency splitter is connected with the master control unit, the master control unit backup, the power divider and the beacon antennae respectively; the power divider is connected with the base station antennae; and the master control unit is also connected with the master control unit backup and a plurality of antennae. The information transmission system for the railway section has the characteristics of high information transmission capacity, high anti-interference capability and high adaptability.

The object of the invention is to provide a driving circuit of a diesel engine position control type actuator. The driving circuit of the diesel engine position control type actuator includes a driving signal input circuit, an over-current protective circuit, a driving current feedback circuit, a pulse feedback circuit and an emergency stop signal input circuit. The driving circuit of the diesel engine position control type actuator has the advantages that (1) the output of a driving logic is realized by using a photoelectric coupler and MOSFET as main logic conversion elements, and the selection of element types is simple and easy to realize; (2) a system can adjust PWM control signals according to a feedback driving current and a driving pulse, thus the self-control of the system is realized; (3) the driving the circuit of the diesel engine position control type actuator has an over-current protection function, when a current is too large, the over-current protective circuit can turnoff a Q8 control switch at the lower end of the actuator to prevent the damage to the circuit caused by the excessive current; and (4) when the driving circuit fails, the actuator can be turned off independently in time through the emergency stop signal input circuit, and the driving the circuit of the diesel engine position control type actuator has a function of safety protection.

The invention discloses a liquid level monitoring system, and relates to the technical field of control. The liquid level monitoring system mainly aims to solve the problems that the traditional wired control wiring is complex, the signal anti-interference capability is weak, the cost is high, the upgrading and maintenance are difficult, the wireless control network is high in power consumption, and the wireless monitoring problem of a mobile terminal cannot be realized. The liquid level monitoring system comprises a processor, a controller and a server, wherein the processor is used for sending a liquid level setting value to the controller by establishing a first thread in double threads, and receiving a liquid level measurement value fed back by the controller by establishing a second thread in the double threads, and performing displaying; the controller is used for calculating a liquid level control parameter and outputting according to the received liquid level setting value sent by the processor by adopting a PID control algorithm, and sending the detected liquid level measurement value to the processor and the server in a wireless communication mode when the control operation of the liquid level control parameter is operated; and the server is used for storing the liquid level measurement value sent by the controller and generating historical data of the liquid level measurement value.

The invention provides an arc-shaped hermetic sealing differential electrical connector with elastic contacts, belonging to the technical filed of electric connectors. The electrical connector is composed of a plug and a socket, the plug includes a plurality of elastic contacts, a plug base, and a plug housing, the plug housing is arc-shaped, the plug base is filled inside the plug housing, the plurality of elastic contacts are fixedly arranged in the plug base via casting glue, the socket includes a plurality of contact contact members, a socket base, and a socket housing, the socket housing is matched with the plug housing in shape and is in plug connection with the plug housing, the socket base is filled inside the plug housing, and the plurality of contact contact members are fixedly arranged on the socket base, are corresponding to the elastic contacts in the socket base one by one, and are in plug connection with the elastic contacts. The differential connector is arc-shaped and is suitable to be arranged on the circular end face, the high density and small size can be realized, and the arrangement of the contacts have the anti-interference function.

The invention relates to the technical field of buoyancy balance of underwater vehicles, and discloses a water volume detection and cabin pressure alarm device of a buoyancy balance water cabin, which comprises a sealing barrel, a liquid level meter, an airtight opening sealing head, a guide rod limiting seat, a sealing end cover, a pressure switch, a watertight connector, a floater and a guide rod, one end of the sealing cylinder is open, and a sealing end cover is arranged at the open end; a liquid level meter for detecting water volume, a pressure switch for alarming cabin pressure and a watertight connector respectively connected with the liquid level meter and the pressure switch are arranged in the sealed cylinder, and the watertight connector is used for transmitting a liquid level signal and a cabin pressure alarm signal in a water cabin to the outside; the sealing end cover is provided with an airtight detection port and an airtight port sealing head; one end of the guide rod is connected with the liquid level meter, and the other end of the guide rod is provided with a floater and connected with a guide rod limiting seat. The device can measure a liquid level position signal in the water storage tank and give an overpressure alarm, and is simple in overall structure, reliable in function and easy to realize.

The invention discloses a central lock system for a vehicle. The central lock system for the vehicle comprises a power supply module, an RF receiving module, a breathing light module, a phase line detection module, a one-key starting module, an electronic door lock detection module, a GPRS module, a code learning key module, a central lock detection module, a high beam detection module, a head indicating lamp module, a vibration alarm module, an MCU control module and a relay control module; and the MCU control module is connected with the RF receiving module, the breathing light module, the phase line detection module, the one-key starting module, the electronic door lock detection module, the GPRS module, a code learning key module, the central lock detection module, the high beam detection module, the head indicating lamp module, the vibration alarm module and the relay control module. The central lock system for the vehicle has the advantages that functions such as a window automatic rolling-up and closing function, an automatic locking and unlocking function, a one-key starting function, a headlight delay function, a GPS positioning system function and an APP remote operationsystem function can be realized, and remote operation is additionally provided.

The invention discloses a CAN remote communication system based on an optical transceiver. The system comprises a near-end device and a far-end device which are connected through an optical fiber. The near-end device and the far-end device each comprise an optical module, an optical fiber data transceiver, a CAN controller and a CAN bus local area network which are connected in sequence. According to the invention, the maximum communication distance of the CAN bus is expanded to the transmission distance of dozens of kilometers from the maximum communication distance of 40m through optical transmission; signals are transmitted through optical fibers, so that the signal anti-interference capability of the system is improved; the far-end device and the near-end device can complete network expansion of multiple groups of CAN buses only through one optical fiber, so the problem that the two devices are connected through multiple cables is simplified, and the problems of electromagnetic radiation, electromagnetic shielding and the like caused by cable connection are avoided; and the two optical transceivers are respectively deployed in a far-end device and a near-end device. The limited range of the CAN bus expansion network subnet can be self-defined according to the specific requirements of a user.