31 results about "Differential mode noise" patented technology

An active compensation device including a first element group including an integrated sensing / compensation unit configured to generate a sensing signal corresponding to at least one of common-mode noise and differential-mode noise on at least two high-current paths, and a second element group including a compensation control unit including a negative impedance converter and configured to generate a compensation signal corresponding to the sensing signal and provide the compensation signal to the integrated sensing / compensation unit. The compensation control unit further including a stabilization unit configured to prevent oscillation caused by the sensed noise. The first element group and the second element group are mounted on a single substrate.

Disclosed in the present invention is a filter circuit. A first PCB layer consists of a power line, a power interface, a second filter capacitor, and a first filter capacitor; the power line comprises a power supply network and a GND network; the second PCB layer is provided with a conductor plane; the power interface is connected to the GND network and is further connected to the conductor plane; the GND network, the second filter capacitor, and the conductor plane are sequentially connected; the power supply network, the first filter capacitor, and the conductor plane are sequentially connected. The circuit design of the circuit structure and the overall layout design idea in the present invention have a good suppression effect on common-mode noise, differential mode noise, radiation noise and conduction noise.

This utility model discloses a frequency converter controller, including a control unit, a first filtering topology, and a second filtering topology. The first filtering topology includes a differential-mode inductor unit, and the second filtering topology includes a common-mode inductor unit. The first filtering topology is connected to the live wire, neutral wire, and protective ground wire, and receives the input signal from the power input terminal, suppresses the differential-mode noise and common-mode noise of the input signal from the power input terminal, and generates a first electrical signal. The second filtering topology receives the first electrical signal, suppresses the differential-mode noise and common-mode noise of the first electrical signal, and generates a second electrical signal. The control unit receives the second electrical signal. Because a differential-mode inductor unit is added to the first filtering topology, the number of magnetic rings can be reduced, the number of installation steps can be reduced, and costs can be optimized.

To provide a technique capable of suppressing differential mode noise in addition to common mode noise in a noise filter connected to a pair of power lines.SOLUTION: A noise filter disclosed in the present specification is a noise filter connected to a pair of power lines, and includes a first bypass capacitor connected between one of the pair of power lines and a ground, a second bypass capacitor connected between the other of the pair of power lines and the ground, a first resistive element connected in series with the first bypass capacitor, and a second resistive element connected in series with the second bypass capacitor.SELECTED DRAWING: Figure 2

The application provides a level shift circuit based on current compensation, a low-voltage pulse signal is connected to a first level input end and a second level output end respectively, so that the two low-voltage pulse signals are converted into two high-voltage pulse signals, and the high-voltage pulse signals are output to a current compensation circuit and a common mode noise elimination circuit through a first level output end and a second level output end; the output of the current compensation circuit and the common mode noise elimination circuit jointly influences the signal state of R end and S end in a latch, and the latch is used for restoring the high-voltage pulse signal into a floating square wave signal with the same phase as the input signal. The application not only can resist high common mode noise, but also has a good inhibitory effect on differential mode noise, and effectively improves the stability and reliability of the level shift circuit.

The utility model belongs to the technical field of electronic components, and particularly relates to a common-mode inductor integrated with differential-mode filtering, which comprises a bottom plate and a common-mode magnetic core, a partition plate is fixedly connected to the top of the bottom plate, a placement groove is formed in the partition plate, a magnetic conductive sheet is arranged in the placement groove, and the common-mode magnetic core is arranged in the placement groove. According to the common-mode inductor, the common-mode magnetic core is matched with the two winding coils, common-mode noise is effectively restrained, the containing groove is formed in the partition plate in the middle of the common-mode inductor, and the magnetic conductive sheet is arranged in the containing groove, so that the common-mode inductor is integrated with a differential-mode inductor and has the capability of filtering differential-mode noise, and the common-mode inductor has the advantages of being simple in structure and convenient to use. An additional differential mode inductor is avoided, and cost reduction and space saving are realized.

The application discloses a wideband active EMI filter circuit and a control method thereof, which comprises a high-frequency common-mode inductance module, an amplification filter module and a differential-mode filter module, the high-frequency common-mode inductance module further comprises two sampling signal output ports, and the sampling common-mode noise is connected to two input ports of the amplification filter module respectively after sampling; the output port of the amplification filter module is connected to the differential-mode filter module, and the differential-mode noise is filtered in the differential-mode filter module after the loop noise current is eliminated. Through the wideband active EMI filter circuit and the control method thereof, the compensation current signal is obtained through a novel sampling mode, the novel sampling mode is adopted, the purpose of wideband filtering is achieved, the stability of the filter is improved, meanwhile, the filter is small in size, wide in frequency band, high in stability, applicable to various space-limited scenes such as aerospace and industrial application, and the hardware design can make the matched product meet the electromagnetic compatibility requirement.

An active compensation device is provided. An active compensation device includes an integrated sensing / compensation unit configured to generate a sensing signal corresponding to at least one of common-mode noise and differential-mode noise on at least two high-current paths, and a compensation control unit including a negative impedance converter and configured to generate a compensation signal corresponding to the sensing signal and provide the compensation signal to the integrated sensing / compensation unit. The compensation control unit further includes a stabilization unit configured to prevent oscillation caused by the sensed noise.

This application provides an AC switching power supply. In this AC switching power supply, the input terminal of each inverter bridge arm is connected to the output terminal of a DC switching power supply; each output terminal of the AC switching power supply is connected to the output terminal of the corresponding inverter bridge arm. In this application, since the common-mode noise of at least two DC switching power supplies cancels each other out, the common-mode noise of the AC switching power supply is suppressed. Furthermore, since in the prior art, the drive signal frequencies of each DC switching power supply in the AC switching power supply are the same, i.e., the number of noise sources at the same frequency point is equal to the number of DC switching power supplies, when the number of DC switching power supplies is the same, the noise sources of this AC switching power supply at the same frequency point will not exceed those in the prior art. Therefore, the differential-mode noise of this AC switching power supply can at least remain unchanged. In summary, the AC switching power supply provided in this application suppresses its own EMI.

The invention discloses an improved XY capacitor plate, and belongs to the field of electronic circuits, the improved XY capacitor plate comprises an X capacitor connected in parallel between a live wire and a zero line, and a first Y capacitor and a second Y capacitor respectively connected between the live wire and a ground wire and between the zero line and the ground wire, and the first Y capacitor and the second Y capacitor adopt symmetrical design and jointly form a pi-type filtering structure; compared with the prior art, differential mode and common mode noise can be efficiently suppressed, the harsh EMC requirement of a ship is met, the safety and reliability of the circuit are greatly improved through the application of the safety capacitor and the redundancy design of the Y capacitor, the electric shock risk caused by element failure is avoided, and part of the filtering function can still be reserved when a single point of fault occurs.

The invention discloses equipment for quickly positioning differential and common mode interference of electronic equipment for a CE102 test item, and belongs to the technical field of electromagnetic compatibility test. Comprising a metal shell, a differential-mode noise suppression module and a common-mode noise suppression module are arranged in the metal shell, four banana sockets and four control switches are arranged on a panel of the metal shell, the banana sockets are used for being connected with a test loop, and the control switches comprise two common-mode control switches and two differential-mode control switches. The two common-mode control switches are respectively connected with the input end and the output end of the common-mode noise suppression module, the two differential-mode control switches are respectively connected with the input end and the output end of the differential-mode noise suppression module, and the control switches are used for selectively connecting the differential-mode noise suppression module or the common-mode noise suppression module into a test loop. According to the invention, the interference type can be rapidly judged, multiple instrument functions are integrated, visual operation is realized through switch switching and light indication, the test efficiency and the positioning accuracy are improved, and on-site rapid troubleshooting is facilitated.

The invention relates to the technical field of signal processing, and discloses a touch integrated display module signal processing method and system. The method comprises the following steps: performing signal acquisition on a display driving circuit of a touch display module during a display frame interval to obtain mixed signal data; performing common-mode noise separation on the mixed signal data according to a common-mode noise reference to obtain touch signal data; identifying a differential mode noise component generated by a pixel driving voltage according to the touch signal data to obtain a differential mode noise separation result and a multi-point touch signal; extracting mixed coordinate data containing real touch points and phantom points according to the multi-point touch signal; based on the differential mode noise separation result, space geometric constraint verification and signal intensity inspection are conducted on the phantom points in the mixed coordinate data, and a touch positioning result is obtained.The phantom point recognition accuracy is ensured, the misjudgment rate is effectively reduced, and the touch reliability of the display module is improved.

The invention relates to a filter, an inverter and a vehicle, the filter comprises a connecting busbar, a magnetic ring and a capacitor, the connecting busbar is used for being electrically connected with an external electronic element, the magnetic ring sleeves part of the connecting busbar, the capacitor can be electrically connected with the connecting busbar, the capacitor comprises a first capacitor and a second capacitor, and the first capacitor and the second capacitor are electrically connected. The first capacitor can be matched with the magnetic ring to form a first differential-mode filter circuit, the second capacitor can be matched with the magnetic ring to form a second differential-mode filter circuit, and the frequency of differential-mode noise suppressed by the first differential-mode filter circuit is different from that of differential-mode noise suppressed by the second differential-mode filter circuit. According to the filter, the first capacitor and the second capacitor are arranged, the frequencies of suppressed noise are different, and a multi-stage and broadband noise absorption network is formed, so that the noise of different frequencies can be suppressed, the frequency of suppressing the noise can be widened, and applicable scenes can be increased.

The invention relates to a filter, an inverter and a vehicle, the filter comprises a connecting busbar, a first magnetic ring, a second magnetic ring and a capacitor, the connecting busbar is used for being electrically conducted with an external electronic element, the first magnetic ring sleeves a part of the connecting busbar, the second magnetic ring sleeves a part of the connecting busbar, and the capacitor is electrically connected with the first magnetic ring and the second magnetic ring. The capacitor can be electrically conducted with the connecting busbar, the first magnetic ring is a common-mode magnetic ring, the first magnetic ring can be matched with the capacitor to form a common-mode filter circuit, the second magnetic ring is a differential-mode magnetic ring, and the second magnetic ring can be matched with the capacitor to form a differential-mode filter circuit. According to the filter, common-mode noise and differential-mode noise are jointly suppressed, the filter can be applied to a high-voltage direct-current system, the first magnetic ring and the second magnetic ring are independent of each other and are designed in a split mode, and measurement of differential-mode inductance and impedance and measurement of common-mode inductance and impedance can be decoupled.

The utility model discloses a common-mode and differential-mode integrated inductor, which comprises a base provided with a separation positioning plate, two positioning grooves and four conductive pins; the magnetic core assembly comprises a closed-loop outer magnetic core and two open-loop inner magnetic cores, the two inner magnetic cores are located on the two opposite sides of the separation positioning plate respectively, the outer magnetic core comprises two outer longitudinal magnetic rods and two outer transverse magnetic rods, each inner magnetic core comprises an inner longitudinal magnetic rod, a center magnetic rod and two inner transverse magnetic rods, a magnetic gap notch is formed in the center of the center magnetic rod, and the two inner transverse magnetic rods are arranged in the center of the center magnetic rod. The central magnetic rod is propped against one side of the separation positioning plate; the two groups of coils are respectively arranged on the two positioning grooves, and each group of coils is wound outside the outer longitudinal magnetic rod and the inner longitudinal magnetic rod. The filter has the function of filtering common-mode noise and differential-mode noise at the same time, can effectively save space, can be widely applied to the field of electromagnetic interference filtering, can reduce loss when magnetic fields repel each other, and is high in consistency of hindering and suppressing the differential-mode noise when being used as two differential-mode inductors.

The utility model discloses a kind of multi-stage filtering integrated module of composite structure, electric drive system and vehicle, belong to new energy electric car electric drive technical field, multi-stage filtering integrated module of composite structure includes upper cover fastener, lower fastener, capacitor filter module, magnetic filter module, bus copper bar, external copper bar, connecting copper column;The magnetic ring is sleeved in the outer circumferential surface of copper bar along copper bar extension direction;Capacitor filter module includes PCB board and the capacitor welded on PCB board, capacitor filter module is crimped with bus copper bar by connecting copper column, another grounding hole is additionally provided on PCB board, ensure that the Y capacitor of connecting bus copper bar and ground can have good electrical contact with metal shell;The multi-stage filtering integrated module of composite structure can guarantee its effective suppression new energy electric car's common mode and differential mode noise in electric drive, while guarantee the simplicity of assembly and the stability of fastening, filtering integrated module meets national standard, with the characteristics of better electrical and structural stability.

The invention discloses a signal acquisition circuit and a signal acquisition method of an accelerometer, and belongs to the technical field of circuits. The accelerometer generates three-axis acceleration current signals; the signal conditioning module is used for converting the acceleration current signals of the three axes into voltage signals, and conditioning each path of voltage signals by using an operational amplifier and a rail-to-rail amplifier to obtain conditioning signals of the three axes; the signal acquisition module carries out triple redundancy sampling on the conditioning signals of the X axis and the Y axis and carries out double redundancy sampling on the conditioning signals of the Z axis; the controller calculates the dynamic weight of each path of sampling signal of the X axis and the Y axis and calculates optimization signals of the X axis and the Y axis according to each path of sampling signal and the dynamic weight, and the dynamic weight corresponding to each path of sampling signal is related to errors of sampling channels of the other two paths of sampling signals; and calculating an optimized signal of the Z axis for the two paths of sampling signals of the Z axis. According to the invention, the interference of common-mode noise and differential-mode noise can be reduced, and the precision influence caused by zero drift and performance difference between channels can be reduced.

The invention provides a high-frequency analog sensing signal remote fidelity transmitting method, which relates to the technical field of sensing signal processing, and comprises the following steps: preprocessing an original sensing signal based on a transmitting end to obtain a differential signal, carrying out carrier frequency modulation on the differential signal to obtain an output signal, and transmitting the output signal to a receiving end, and the receiving end demodulates and digitally processes the received signal to obtain a digital sensing signal. On the basis of differential frequency modulation of sensing signals, remote high-fidelity transmission of high-frequency analog signals of a complex noise interference field is achieved in combination with depth filtering, the physical anti-interference characteristic of differential frequency modulation is fully utilized on the premise that expensive digital transformation of a sensor end is not needed, and the high-fidelity transmission of the high-frequency analog signals of the complex noise interference field is achieved. And complex common-mode and differential-mode noise is intelligently separated and eliminated through a deep learning filter at a receiving end, so that the system cost and the complexity of a sending end are remarkably reduced, and the signal fidelity and the transmission reliability far superior to those of a traditional method are realized.

The utility model discloses an EMI (Electro-Magnetic Interference) suppression circuit, comprising a low-frequency common-mode suppression module which is used for suppressing power-frequency harmonic waves and low-frequency conduction noise and is composed of a three-phase ferrite core common-mode inductor L1; the differential mode discharge module is used for discharging differential mode noise and is composed of an X capacitor C1, an X capacitor C2 and an X capacitor C3; the high-frequency common-mode suppression module is used for suppressing high-frequency switching noise and diode reverse recovery ringing and is composed of a three-phase common-mode inductor L2; the common-mode grounding module is used for guiding common-mode noise to be discharged through a ground wire and is composed of a Y capacitor C4, a Y capacitor C5 and a Y capacitor C6, one end of each Y capacitor is connected with the three-phase line, and the other end of each Y capacitor is in common ground. According to the EMI suppression circuit, through collaborative design of the two stages of common-mode inductors, the differential-mode discharge module and the common-mode grounding module, the differential-mode inductor is omitted, the common-mode noise suppression capability is ensured, the circuit size is reduced, and the cost is saved.

The invention relates to an electrical circuit (6) comprising: two input terminals (13) connectable to a DC voltage; a control unit (7p, 7s); a first switching arm (B1, B3) comprising two controllable electronic switches (12) connected in series on either side of a first midpoint, the switches of the first arm being controlled by the control unit according to a first duty cycle; a second switching arm (B2, B4) comprising two controllable electronic switches (12) connected in series on either side of a second midpoint, the switches of the second arm being controlled by the control unit according to a second duty cycle; inductance units (10, 20) for contactless energy exchange consisting of inductors, mounted between first and second midpoints (14, 15), the first arms (B1, B3) and the second arms (B2, B4) being mounted in parallel, the circuit comprising a filter unit (11, 21) for filtering common and / or differential mode noise.

This invention relates to an MLVDS receiver circuit based on BiCMOS technology, comprising a common-mode converter circuit, a pre-amplifier circuit, type 1 and type 2 control circuits, a hysteresis comparator circuit, and a differential-to-single-ended converter circuit. The common-mode converter circuit compresses the input signal with a wide common-mode range; the pre-amplifier circuit identifies and amplifies the compressed differential signal; the type 1 and type 2 control circuits control the operating mode of the MLVDS receiver; the hysteresis comparator introduces hysteresis while amplifying the differential signal, suppressing differential noise and providing anti-interference capability; the differential-to-single-ended converter circuit converts the differential signal to a single-ended signal. This invention provides an MLVDS receiver circuit based on BiCMOS technology. This circuit, implemented using BiCMOS technology, can achieve a wide common-mode range input through a resistor divider network, and simultaneously implements both type 1 and type 2 operating modes, meeting the requirements of the MLVDS standard.

The application belongs to the technical field of power electronics, and relates to a CM-DM integrated active EMI filter with adjustable common-mode and differential-mode attenuation, comprising: a first noise attenuation circuit and a second noise attenuation circuit; the first noise attenuation circuit and the second noise attenuation circuit are both composed of a detection link, an amplification link and an injection link; the application takes a negative bus as a reference, two operational amplifiers use the same power supply system, and common-mode and differential-mode noises can be simultaneously and effectively attenuated through constructing a proper compensation current path, and common-mode and differential-mode insertion losses can be respectively changed by changing the gains of the first and second noise attenuation circuits; therefore, the application realizes the separate adjustment of common-mode and differential-mode noise attenuation capabilities.

Provided is a noise filter that does not cause magnetic saturation by using a magnetic core in a circuit through which a large current flows. A large current is shunted to a plurality of conductors, and a noise filter using a magnetic core is provided in each of the plurality of conductors. The magnetic core may be configured such that one electrical conductor passes through a plurality of different magnetic cores, and the frequency band can be broadened by varying the characteristics of the plurality of magnetic cores. It is also possible to provide a core-type noise filter capable of coping with common-mode noise in addition to blocking differential-mode noise.

Motor-driven compressor (10) comprising: a compression unit (13) configured to compress a fluid, a motor (14) configured to drive the compression unit (13), an inverter device (15) configured to drive the motor (14), and a housing (11) in which the compression unit (13), the motor (14), and the inverter device (15) are housed, wherein the inverter device (15) comprises: an inverter circuit unit (43) configured to convert DC power to AC power, and a noise reduction unit (50) provided on an input side of the inverter circuit unit (43) and configured to reduce common-mode and differential-mode noise, the noise reduction unit (50) comprising: a common-mode choke coil (51) configured to reduce common-mode noise, and a smoothing capacitor (52).which together with the common-mode choke coil (51) forms a low-pass filter (56), and a first damping section (54) made of a non-magnetic material and configured to reduce differential-mode interference, the common-mode choke coil (51) having: an annular core (60), a first winding (61) wound around the core (60), and a second winding (62) wound around the core (60) and spaced apart from the first winding (61), the first damping section (54) being configured to surround the first winding (61) and the second winding (62), the first damping section (54) being configured such that an induced current flows into the first damping section (54) to generate a magnetic flux that counteracts changes in a leakage flux that spreads from the core (60), the interference reduction unit (50) further comprising a second damping section (55),which is made of a magnetic material and is configured to reduce differential-mode interference, and the second damping section (55) is arranged on a side of the first damping section (54) opposite the common-mode choke coil (51).

The invention relates to a differential mode and common mode integrated inductor and a switching power converter with the same, the inductor scheme is that a second end of a third winding is connected with a second end of a first winding, and an inductor structure with differential mode and common mode integration is provided. According to the switching power converter scheme, a transformer is provided with a primary side and a secondary side; the primary side circuit is coupled to the primary side. The primary side circuit includes a power supply impedance stabilization network and a noise cancellation circuit. The supply impedance stabilization network receives an input power supply. And the noise elimination circuit is connected with the power supply impedance stabilization network and comprises a safety Y capacitor bank and a differential-mode and common-mode integrated inductor. The differential-mode and common-mode integrated inductor is coupled to the safety Y capacitor bank. The voltage conversion circuit is coupled between the differential mode and common mode integrated inductor and the primary side. On the premise that independent magnetic elements are not newly added, the shared iron core magnetic circuit can be used as an integrated inductor, and miniaturization of the elements is facilitated. 2, the EMI emission intensity of common-mode and differential-mode noise current is reduced; and 3, a common-mode noise elimination circuit structure which is completely composed of passive elements.

The invention provides a PCB common-mode and differential-mode integrated adjustable inductance filter, and belongs to the technical field of circuit magnetic filtering. The invention discloses a PCB common-mode and differential-mode integrated adjustable inductance filter, and the filter comprises a PCB substrate. The magnetic core structure comprises two split type magnetic cores which are oppositely arranged, and the two split type magnetic cores are detachably buckled on the PCB substrate; the winding structure is arranged on the PCB substrate in a same-direction common-mode mode, and the filtering frequency band and the impedance can be adjusted by adjusting the air gaps between the middle columns and the side columns of the two split type magnetic cores. The two split type magnetic cores are combined together to form the common-mode and differential-mode integrated magnetic core, the winding structure is wired along the PCB substrate in the same-direction common-mode mode, on one hand, differential-mode components with different impedances can be designed based on adjustment of air gaps between the middle columns and the side columns of the split type magnetic cores; and on the other hand, common-mode filtering with different inductance values can be obtained based on different winding structure turn ratios, so that impedance can be conveniently designed for different circuits to effectively suppress common-mode and differential-mode noise, and the common-mode and differential-mode filter can be flexibly applied to different circuits.

The utility model discloses a kind of multi-stage filtering integrated devices, electric drive system and vehicle, belong to new energy electric car electric drive technical field, multi-stage filtering integrated devices include structural member, multiple magnetic elements, multi-stage capacitor filter unit and copper bar;The copper bar is fixed on structural member, and copper bar end is used for connecting load by lead through magnetic element, other magnetic element is set on copper bar and is connected with structural member;Multi-stage capacitor filter unit is interval arranged along the arrangement direction of copper bar, and capacitor filter unit includes PCB board, and capacitor is set on it, PCB board is across set on the top of copper bar, grounding point of PCB board is embedded with ground terminal, and the pin of capacitor is respectively connected with copper bar and ground terminal of PCB board;The multi-stage filtering integrated device can effectively suppress common mode and differential mode noise of electric drive in new energy electric car, filtering performance meets international standard, and has the characteristics of strong electrical stability and strong structure.

The invention relates to the related technical field of circuit substrates, and discloses a DCDC common-mode noise suppression circuit for an electronic control unit, which comprises the electronic control unit, and the electronic control unit distributes a power supply through a DC-DC converter and is a system block diagram of an electric power steering electronic control unit. The whole vehicle power input supplies power to the power management chip, the driving chip and the motor driving circuit. The power supply management chip is responsible for distributing a power supply and supplying power to the CAN transceiver, the microprocessor, the motor angle sensor, the TAS sensor and other chips; the microprocessor is interconnected with other chips; through the synergistic effect of the normal filter and the common-mode filter, in combination with the ground plane segmentation design and the conduction effect of the conductive metal screws, efficient suppression of differential-mode noise and common-mode noise is realized near a noise emission source, the electromagnetic disturbance of an electronic control unit is effectively reduced, and the noise suppression effect of the electronic control unit is improved. And the electromagnetic compatibility of the electronic control unit and the whole vehicle is improved.

Provided is an active filter device capable of effectively reducing common mode noise and differential mode noise and optimizing filter characteristics. The active filter device includes an inverting amplifier circuit 37 that inverts and amplifies a common mode voltage and a differential amplifier circuit 64 that differentially amplifies a differential mode voltage, and an output voltage of the inverting amplifier circuit 37 is applied as a common mode compensation voltage to Y capacitors 21, 22, an output of the differential amplifier circuit 64 obtained by amplifying a voltage of a positive-side power supply line 11 is applied as a differential mode compensation voltage to a negative-side X capacitor 42, and an output of the differential amplifier circuit 64 obtained by amplifying a voltage of a negative-side power supply line 12 is applied as a differential mode compensation voltage to a positive-side X capacitor 41.

The present disclosure provides a microwave frequency measurement system, comprising: an amplitude measurement module, configured to modulate a to-be-measured microwave signal on a continuous wide-spectrum light wave signal to generate a modulated signal, and divide the modulated signal into an upper modulated signal and a lower modulated signal, and convert the upper modulated signal and the lower modulated signal into a first electrical signal and a second electrical signal after introducing a first delay and a second delay, respectively; and a frequency measurement module, configured to calculate a power comparison value of the first electrical signal and the second electrical signal, and obtain a frequency of the to-be-measured microwave signal based on a preset mapping relationship between the power comparison value and the frequency of the microwave signal. The present disclosure removes difficult-to-measure parameters and suppresses common-mode noise by constructing a power comparison value, and suppresses differential-mode noise in a preset power comparison function by a machine learning algorithm, thereby improving the accuracy of frequency measurement.