1298 results about "Frequency mixer" patented technology

This disclosure describes an auto-calibration of mixers in a quantum orchestration platform. Predistortion is computed according to an RF signal that is downconverted with a local oscillator tone that is offset from an upconverter tone. Three tones present in the original RF signal are distinguished and used to construct a cost function. The minimization of the cost function is used to cancel an unwanted LO leakage and an image tone. Because the quantum orchestration platform generates both the unconverted IQ signals and the cost function for their optimization, the optimization can be performed in real time inside a single device without the need to communicate with external devices. This allows for the optimization of single sideband upconverted signals in a fraction of the time it typically takes using distributed systems employing separate waveform generators and spectrum analyzers.

The invention discloses an optical frequency comb repetition frequency locking device and method based on automatic power control, and relates to the technical field of optical frequency combs, the device comprises an optical frequency comb optical system, an optical fiber length automatic control system and an automatic power control system, the optical frequency comb optical system is used for generating optical frequency comb repetition frequency, the optical fiber length automatic control system locks the optical frequency comb repetition frequency output by the optical frequency comb optical system, and the automatic power control system is used for adaptively adjusting the signal power in a corresponding link when the optical frequency comb optical power or the reference source power changes. The input power of the mixer local oscillator and the radio frequency port is maintained at the preset power; according to the technical scheme of the invention, the stability and accuracy of the input power of the radio frequency and local oscillation port of the mixer are improved, the suppression of noise in a link is enhanced, a phase-locked loop of an optical fiber length automatic control system can be maintained in an optimal working state for a long time, and the practicability of an optical frequency comb product is improved.

The invention discloses a high-throughput satellite communication terminal system, which comprises a radio frequency channel unit, a signal processing unit, a terminal processing unit, a power supply management unit and an anti-electromagnetic interference module, and is characterized in that the radio frequency channel unit carries an agile device and a power amplifier and is used for realizing bidirectional conversion between a baseband signal and a radio frequency signal; communication frequencies of a Ka frequency band, a valley value of 5GHz and a peak value of 40GHz are supported, a zero intermediate frequency receiver structure is adopted, image frequency interference is eliminated through one-time frequency conversion to a baseband, and a high-integration design that a radio frequency signal directly enters a frequency mixer after passing through an antenna, a radio frequency filter and a low-noise amplifier is realized. According to the high-throughput satellite communication terminal system, the coverage problem of traditional communication in a blind area of a power grid is solved, safe, efficient and stable transmission of power data is realized, the emergency communication capability and the equipment environment adaptability are remarkably improved, and key technical support is provided for constructing global visual monitoring and intelligent scheduling of the digital power grid.

The invention discloses a frequency source synthesis system and method based on a frequency agility radar, and belongs to the technical field of microwave radio frequency, and the method specifically comprises the steps: generating a target clock signal, carrying out the frequency processing of the target clock signal to generate a frequency multiplication signal, and dividing the frequency multiplication signal into two clock signals through a power divider; performing frequency multiplication processing on one path of clock signal, taking the processed signal as a clock reference signal of a direct digital synthesizer, generating an analog signal according to the clock reference signal, and calibrating the analog signal as an output signal; performing frequency multiplication processing on the other path of clock signal, and taking the processed clock signal as a local oscillation signal of the frequency mixer; performing frequency conversion processing to obtain a frequency mixing signal, performing quadruplicated frequency processing on the frequency mixing signal, and calibrating the processed frequency mixing signal as a final output signal; according to the invention, the frequency source has the characteristics of low phase noise, rapid agility, fine resolution and miniaturization at the same time.

The invention relates to the technical field of signal detection, in particular to a weak electric field signal detection method and system. According to the invention, complete information of frequency, amplitude and phase of a to-be-measured electric field signal is obtained at the same time in one measurement of the injection locking phonon laser, a to-be-measured laser amplitude spectrum and a to-be-measured laser phase spectrum are generated by the same injection locking phonon laser, and the amplitude signal and the phase signal which are measured and received must arrive at the same time. The two are simultaneous in time and have natural orthogonality in physics; therefore, compared with a traditional double-phase lock amplifier for analyzing two asynchronous signals to be measured received by two frequency mixers, the method for analyzing the laser amplitude spectrum and the laser phase spectrum to be measured to obtain the electric field information to be measured has the advantages that the accuracy is higher; the double-phase lock amplifier solves the technical problem of measurement errors caused by deviation of to-be-measured signals received by two frequency mixers in a traditional double-phase lock amplifier.

The invention discloses an independent double-single-side-band direct detection system based on geometric shaping and digital chaotic encryption, and belongs to the field of terahertz communication. According to the detection system, an external cavity laser ECL of a sending end generates continuous optical carriers, the continuous optical carriers are input into an I / Q modulator, a TX-DSP module generates two independent vector radio frequency signals of GS-QPSK and GS-NQAM through geometric shaping and a three-dimensional multi-vortex chaos system technology, the I / Q modulator is driven to modulate the input optical carriers, and the optical carriers are transmitted to a receiver. After being amplified, the terahertz signals are input into a one-way carrier photoelectric detector for frequency beating to obtain independent double-sideband terahertz signals, the independent double-sideband terahertz signals are input into a frequency mixer of a receiving end for frequency mixing with generated local oscillation signals, down-conversion of the signals is achieved, and fundamental frequency signals are obtained; and then the data are input to an RX-DSP module, normalization, down-sampling, signal separation, de-mapping, symbol-level and bit-level decryption and other operations are carried out, and finally two paths of original data are obtained to solve the bit error rate. According to the invention, the system communication capacity is improved, and the security of independent double-sideband signal transmission is improved.

The invention discloses a differential signal synthesis circuit of a double-IQ mixer, which belongs to the technical field of radio frequency microwave testing and comprises two single-ended IQ mixing modules, a 180-degree phase shift module and an in-phase combination module or a power division module. The single-ended IQ frequency mixing module is used for up-converting the single-ended IQ baseband signal to radio frequency or down-converting the radio frequency signal to the single-ended IQ baseband signal; the 180-degree phase shift module is used for converting an input signal into two paths of signals with a phase difference of 180 degrees; and the power division module is used for converting the radio frequency input signal into two paths of signals with the phase difference of 0 degree. According to the invention, the IQ mixer with a differential structure is constructed, so that the microwave band of the IQ mixer is comprehensively improved in the index aspects of local oscillator leakage, even-order component suppression, common-mode interference suppression, signal-to-noise ratio and the like; according to the invention, single-ended IQ mixers with various types and complete frequency bands can be constructed into a differential structure form, and signal indexes in numerous application scenes are improved.

The present invention provides a transceiving coaxial phased array LiDAR chip and a control method therefor. The transceiving coaxial phased array LiDAR chip comprises: a laser emitting unit, a general beam splitter, a transceiving phased array, a balanced detector array and a signal processing and control unit; a phase modulator of a phased array unit in the transceiving phased array is separately connected to light-exit paths of the general beam splitter, and performs phase modulation on light output by the general beam splitter; after that, the light is divided into reference light and signal light, the signal light passing through a first port and a second port of a circulator and then being radiated by grating radiation antennas into a free space, and the reference light passing through a frequency shifter and then being input into a 90-degree optical mixer together with an echo optical signal returned by a third port of the circulator; then, balanced detectors receive output signals, convert same into electric signals and transmit same to the signal processing and control unit, so as to calculate three-dimensional depth and / or speed information of a target region. By means of a transceiving coaxial phased array LiDAR and a coherent detection means, the present invention achieves chip integration of a transmitting end and a detection end of the LiDAR, and has higher signal-to-noise ratio and integration degree compared with traditional LiDAR systems.

The invention provides a microwave superheterodyne frequency sweep measurement system based on Rydberg atoms, and belongs to the technical field of microwave frequency measurement. The laser module excites detection light of 780 nm and coupling light of 480 nm, and the two beams of light are reversely input into the atomic gas chamber through the dichroscope; signal microwaves are generated by a radio frequency signal source and are radiated to the position of the atomic gas chamber through the horn antenna; local oscillation microwaves are generated by the microwave module and are also radiated to the position of the atomic gas chamber through the horn antenna; the atomic gas chamber serves as a mixer to form a difference frequency signal; the spectrum analyzer is used for monitoring low-frequency difference frequency signals generated in the frequency mixing process in real time and recording signal intensity in real time. According to the invention, high-precision and wide-band microwave frequency measurement is realized, continuous and smooth frequency sweeping response can be provided in a frequency range, and absolute frequency detection of microwave signals is realized under the condition that a complex frequency comb technology is not introduced. The hardware architecture is simplified, the automation degree is improved, and integration, popularization and application are facilitated.

The invention discloses a frequency measurement circuit and a frequency measurement method, belongs to the technical field of frequency measurement, and mainly solves the problems that the existing frequency measurement is large in frequency error, low in frequency measurement speed and narrow in frequency measurement bandwidth, and cannot meet the requirements of radar communication. The frequency measurement circuit comprises an FPGA control module, a reference clock circuit connected with the FPGA control module, a DDS frequency output circuit, a phase discrimination frequency control circuit, a frequency mixer connected with the phase discrimination frequency control circuit, and a radio frequency input circuit connected with the frequency mixer. According to the frequency measurement technology, the DDS output frequency is directly collected according to the characteristic that the FPGA collects the low frequency, the DDS output frequency serves as the phase discriminator phase discrimination frequency, frequency measurement is conducted in a phase locking mode, and the frequency measurement precision is high; the phase discriminator is set to have a fixed frequency dividing ratio, the phase discriminator is configured with a fixed register, a DDS frequency sweeping mode is adopted, and the frequency measurement time is short by changing the phase discrimination frequency of the phase discriminator to the output frequency of the phase-locked loop; and the frequency measurement bandwidth is increased by using a radio frequency input frequency division mode.

The invention provides a signal transceiving test system for simulating a shared local oscillator and a calibration method thereof, and the system comprises a signal generation module which outputs a baseband signal; the first local oscillator module comprises a first clock source, a first phase-locked loop and a first frequency multiplication channel, and the first frequency multiplication channel outputs a first local oscillator signal; the first frequency mixer is used for mixing the baseband signal and the first local oscillator signal to generate a modulation signal; the second local oscillator module comprises a second clock source, a second phase-locked loop and a second frequency multiplication channel, and the second frequency multiplication channel outputs a second local oscillator signal; the second frequency mixer is used for mixing the modulation signal and the second local oscillation signal to generate a demodulation signal; the signal analysis module is used for receiving and analyzing the demodulated signal; and the controller adjusts the first phase-locked loop or the second phase-locked loop. The problem that the phase difference of different local oscillators cannot be predicted can be solved while mutual interference of the shared local oscillators is avoided, so that the test calibration precision is improved.

A system may include a digital front end (DFE). The DFE may be configured to generate a command signal. The system may also include a sweeper. The sweeper may be configured to generate an intermediate in-phase signal, an intermediate quadrature signal, and a LO signal based on the command signal. In addition, the system may include a mixer. The mixer may be configured to generate a mixed in-phase signal based on the intermediate in-phase signal and the LO signal. The mixer may also be configured to generate a mixed quadrature signal based on the intermediate quadrature signal and the LO signal. Further, the system may include an amplifier. The amplifier may be configured to generate an in-phase signal based on the mixed in-phase signal and an amplification setting. The amplifier may also be configured to generate a quadrature signal based on the mixed quadrature signal and the amplification setting.

The invention provides a frequency mixer and signal transmission equipment, and belongs to the technical field of communication. In the scheme provided by the invention, the mixer can transmit the local oscillator signal through the slot line, and transmit the first signal, the second signal and the third signal through the microstrip line. Therefore, it can be ensured that the transmission mode of the local oscillator signal is different from the transmission mode of the first signal and is different from the transmission modes of the second signal and the third signal, that is, the transmission mode isolation of the local oscillator signal from the first signal and the transmission mode isolation of the local oscillator signal from the second signal and the third signal can be realized. The transmission modes of the local oscillator signal and other signals are isolated, so that the leakage of the local oscillator signal at other signal ports can be effectively reduced, and the performance of the mixer is effectively improved.

The invention provides a GEO communication satellite uplink signal Doppler frequency compensation method and device. The method comprises the following steps: acquiring a satellite orbit determination result corresponding to a GEO communication satellite; determining a Doppler compensation frequency curve according to the satellite orbit measurement result and the local frequency of the frequency conversion of a satellite transponder configured in the GEO communication satellite; and compensating a first uplink signal to be transmitted from the ground station to the GEO communication satellite by using the Doppler compensation frequency curve through the compensation frequency mixer, and transmitting the compensated first uplink signal to the GEO communication satellite. According to the invention, under the condition that the user receiver is non-inductive, the carrier frequency and the spreading code rate of the user receiver are changed in equal proportion, so that the user receiver can adopt a receiving algorithm of the carrier-assisted spreading code rate to improve the sensitivity.

The invention discloses a dual-channel millimeter wave transmitter, a receiver and a transceiver system. The transmitter comprises a baseband signal processing circuit, a local oscillator signal processing circuit and a radio frequency front-end circuit comprising a high-frequency channel power amplifier, a low-frequency channel power amplifier and a signal synthesis switching circuit. The radio frequency front-end circuit selectively outputs signals of a high-frequency channel or a low-frequency channel through the signal synthesis switching circuit, and a current adjusting circuit is arranged in the baseband signal processing circuit and used for adjusting mismatch of a switching tube in the mixer. The disclosure also provides a dual-channel millimeter wave receiver and transceiver system based on the same concept. According to the invention, the problem of performance bottleneck of a single-channel transceiver in broadband application is solved, the system linearity is improved, the processing capability of high-order modulation signals is improved, and high power efficiency and high integration level are maintained through optimized circuit design.

The invention discloses a microwave reflectometer system. An arbitrary waveform generator generates a microwave signal through an X-Ku signal source unit; the coaxial directional coupler divides the generated microwave signal into two paths, one path enters the transmitting unit, and the other path enters the reference unit; a microwave signal entering the transmitting unit is transmitted into the plasma through a fundamental mode rectangular waveguide in the transmitting circuit; the microwave signal entering the reference unit is subjected to flight time compensation through a delay line and then is mixed with a reflected signal received by the receiving unit in a balanced mixer; the calibration unit carries out secondary frequency mixing on the dispersion calibration voltage-time curve signal and the signal obtained after primary frequency mixing of the balanced frequency mixer so as to eliminate dispersion interference; the acquisition card acquires an output signal after secondary frequency mixing of the calibration unit. The system can be integrated with an ion cyclotron resonance antenna, the inherent defects of large attenuation and high dispersion of a long-distance fundamental mode waveguide are overcome, and a high-frequency fundamental mode waveguide through-wall scheme meeting ultrahigh vacuum performance index requirements is realized.

The invention discloses a radio frequency signal matching network, a frequency mixer, a phase shifter, a radar sensor and electronic equipment, the radio frequency signal matching network comprises a first inductor with an I-path input end, a second inductor with a Q-path input end, and a third inductor which is inductively coupled with the first inductor and the second inductor, and the third inductor is provided with an output end; wherein the I-path input end is set to receive I-path radio frequency signals, and the Q-path input end is set to receive Q-path radio frequency signals.

The invention belongs to the technical field of optoelectronic devices, and provides a laser gyroscope frequency stabilization system and a frequency stabilization method thereof.The laser gyroscope frequency stabilization system comprises a large laser gyroscope to be subjected to frequency stabilization, an electro-optical modulator, an adjusting light path, a signal generator, a mode matching mirror set, a PID regulator, a frequency mixer, a photoelectric detector, an ultra-stable cavity, a low-pass filter, a computer and a data acquisition card; and a square transmission light path is arranged in the ultra-stable cavity. According to the invention, the problem of insufficient isolation caused by an optical isolator consisting of a polarization splitting prism and a 1 / 4 wave plate is effectively avoided, the influence of an optical feedback effect is reduced, and the optical isolator is better adapted to the field of high-precision measurement related to a large laser gyroscope.

A material complex dielectric constant measuring system belongs to the technical field of microwave dielectric measurement and comprises a self-harmonic oscillator, a phase-locked loop and an envelope detector. The self-harmonic oscillator comprises a resonator, a first radio frequency amplifier and a first power divider; two ends of the resonator are respectively connected with the output end of the first radio frequency amplifier and the input end of the first power divider; the phase-locked loop comprises a mixer, a low-pass filter and a voltage-controlled oscillator. The phase-locked loop and the envelope detector are used for demodulating signals and mapping signal frequency and power to direct-current voltage, the voltmeter is used for measuring phase-locked loop control voltage and envelope detector output voltage, and the relation between the size of the complex dielectric constant of the material and the voltage is obtained. The phase-locked loop control voltage can be measured from the voltage control end of the voltage-controlled oscillator. The system is simple in structure, small in size, easy to carry and suitable for field rapid measurement and mobile application, the measurement result is more comprehensive, and the system has higher measurement precision and stability.

A mixer includes a mixing stage, and a first transistor and a second transistor coupled to the mixing stage. A gate of the first transistor is coupled to a first input of the mixer, and a gate of the second transistor is coupled to a second input of the mixer. The mixer also includes a first source resistor coupled to a source of the first transistor, and a second source resistor coupled to a source of the second transistor. The mixer further includes an amplifier having a first input coupled to the source of the first transistor, and a second input coupled to the source of the second transistor. The amplifier is configured to adjust at least one bias voltage of at least one of the first transistor and the second transistor based on a differential voltage between the first and second inputs of the amplifier.

The invention provides an orthogonal down-conversion mixer, which comprises a first signal input port, a signal processing module and a mixing module, and is characterized in that a radio frequency signal is converted into a differential radio frequency signal through the first signal input port, and phase shift, amplification and impedance matching are performed on an initial local oscillator signal through the signal processing module; a first local oscillator signal and a second local oscillator signal are used for receiving a differential radio frequency signal, two local oscillator signals with orthogonal phases are obtained, the differential radio frequency signal is amplified through a pseudo-differential structure in a frequency mixing module, and frequency mixing is performed on the first local oscillator signal, the second local oscillator signal and the amplified differential radio frequency signal to obtain two target intermediate frequency signals. According to the orthogonal down-conversion mixer provided by the invention, the differential radio frequency signal is amplified through the pseudo-differential structure, the noise coefficient and power consumption of the mixer are reduced, the mixing speed is increased through the two local oscillator signals, and the noise coefficient of the mixer is further reduced.

The invention provides an automatic gain control system and method based on radio frequency envelope detection, and a receiver. The bias end of an LNA is connected with an automatic gain control module; an envelope detection circuit is also connected between the output end of the LNA and the frequency mixer, and the envelope detection circuit is connected with an automatic gain control module; the detection module is used for outputting a preset level saturation indication signal to the automatic gain control module when an input signal which comes from the output end of the LNA and is greater than preset power is detected; the control end of the VGA is connected with the automatic gain control module; the output end of the ADC is connected with the automatic gain control module; the automatic gain control module performs automatic adjustment of receiver link gain. The fast envelope detection provides extra information, the automatic gain control response speed of the system is improved, the circuit design is simple, the power consumption is smaller, only a smaller chip layout area is occupied, and the cost is lower.

The invention discloses an optical fiber signal transmission system and method based on quantum noise encryption, and relates to the technical field of optical fiber communication, and the system comprises a composite modulation transmitting module, a dispersion compensation relay module, a coherent receiving module and a digital signal processor. The composite modulation transmitting module comprises an electro-optical modulator and a quantum noise randomization encoder; the dispersion compensation relay module comprises an adjustable dispersion compensator and a Raman amplifier; the coherent receiving module comprises a local oscillator laser and a 90-degree optical mixer; a digital signal processor includes a clock recovery unit and a maximum likelihood sequence detector. All the modules are sequentially connected and cooperatively work. And the adjustable dispersion compensator dynamically applies reverse dispersion compensation calculated based on a dispersion coefficient and a transmission distance according to the dispersion amount monitored in real time. According to the invention, through technologies of quantum noise encryption, dynamic dispersion compensation, Raman amplification, coherent reception and the like, safe and efficient transmission with single-wave 400Gbps and 100km transmission bit error rate less than or equal to 1 * 10 <-12 > is realized.

The photonic integrated chip comprises a substrate, a demultiplexer and a light guide assembly, and the light guide assembly and the demultiplexer are integrated on the substrate; the light guide assembly comprises a first light splitting coupler, a second light splitting coupler and a frequency mixer, and the first light splitting coupler is in optical communication connection with the output end of a corresponding channel of the demultiplexer so as to allow the demultiplexer to transmit an optical signal to the first light splitting coupler; the first light splitting coupler is used for splitting a received optical signal into local oscillation light and signal light, and the first light splitting coupler is in optical communication connection with the second light splitting coupler and the frequency mixer so as to allow the first light splitting coupler to transmit the local oscillation light to the frequency mixer and transmit the signal light to the second light splitting coupler; the second light splitting coupler is used for transmitting the signal light to a detection object and receiving echo signal light fed back by the detection object, and the second light splitting coupler is in optical communication connection with the frequency mixer so as to allow the second light splitting coupler to transmit the echo signal light to the frequency mixer.

The invention belongs to the technical field of terahertz mixer testing, and relates to an efficient testing method and system for a millimeter wave terahertz mixer. The test system comprises a vector network analyzer and a terahertz S parameter test module. According to the difference of radio frequency and local oscillation frequency caused by the frequency mixing times of a to-be-tested frequency mixer, test platforms of two structures are arranged; the first test platform comprises a vector network analyzer, a first terahertz S parameter test module and a second terahertz S parameter test module, wherein the first terahertz S parameter test module and the second terahertz S parameter test module are connected with the vector network analyzer. The second test platform comprises a vector network analyzer and a terahertz S parameter test module connected with the vector network analyzer. According to the test method provided by the invention, a vector network analyzer host based on a microwave frequency band is combined with a terahertz S parameter test module to realize efficient test of a terahertz frequency band mixer; the problems that an existing terahertz frequency mixer is low in testing efficiency, complex in testing and high in cost are solved.

An electronic device may include wireless circuitry with a mixer. The mixer may include a transconductor with first and second input transistors, a switching quad with first and second pairs of mixer transistors, and a transformer coupled between the transconductor and the switching quad. The transformer may have a primary winding and a secondary winding. The transformer may have a conductive path that couples a center tap contact of the primary winding to a center tap contact of the secondary winding. The conductive path may configure the transformer to share a DC bias current between the transconductor and the switching quad. This may eliminate the need to bias the transconductor and the switching quad using different power supply voltages, thereby minimizing power consumption without sacrificing performance.

The invention discloses an in-phase and quadrature demodulation phase modulation optical heterodyne frequency stabilization system for inhibiting an RAM (Random Access Memory), which relates to the technical field of laser frequency stabilization and comprises a laser, an electro-optical modulator, a circulator, an optical resonant cavity, a photoelectric detector, a phase shifter, a frequency mixer, a summator, a low-pass filter, a signal generator and a signal acquisition and processing module. Laser emitted by the laser is modulated by the electro-optical modulator and then enters the circulator, the circulator receives reflected light of the optical resonant cavity and emits the reflected light to the photoelectric detector, and all error signals are obtained through the frequency mixer and the low-pass filter. All error signals are added through an adder and then are input into a signal acquisition and processing module for feedback, so that the frequency of laser emitted by the laser is locked to the resonant frequency of the optical resonant cavity; according to the frequency stabilization system, a plurality of modulation frequencies are introduced to modulate the laser phase in the electro-optical modulator, so that the influence of RAM noise on frequency stabilization is suppressed.

The invention discloses a DP-MZM-based reconfigurable mixer with phase shift and image rejection functions, and belongs to the field of microwave photon signal processing. By adjusting an input radio frequency signal and a direct current bias voltage of the DP-MZM1, four different LO frequency doubling and mixing functions can be realized. By controlling the angle alpha between the polarization direction of the polarization analyzer and one axis of the modulator, the phase of the generated signal can be flexibly tuned in the range of 0-360 degrees. When combined with the optical frequency comb, the multi-channel multi-band frequency conversion system can be expanded into a multi-channel multi-band frequency conversion system with independent phase tuning capability by utilizing the channel switching and frequency slot selection functions of the wavelength selection switch, and parallel output of various frequency mixing results can be realized. By adjusting the phase difference between the two-channel output signals, I / Q mixing, double-balanced mixing and image rejection mixing can be configured. The scheme is not influenced by direct current bias drift, the system complexity is reduced, and the frequency conversion efficiency is improved.

The invention discloses a voltage transformer insulation state evaluation and dielectric self-repairing method and system. The method comprises the steps that a quantum dot array sensor is embedded in the surface of a voltage dividing capacitor unit of a CVT to obtain the capacitance value of a CVT insulation layer; a high-frequency scanning signal is injected into an end screen input port of the CVT, a local oscillator and a quantum mixer are arranged at an output port, and a dielectric loss factor is obtained; carrying out circuit analysis on the CVT insulation circuit, converting an insulation layer capacitance value and a dielectric loss factor into a capacitor breakdown number and a dielectric loss abnormal characteristic parameter, respectively taking the parameters as inputs of a WOA-based optimized DBA model, and obtaining a capacitor breakdown error variable quantity and a dielectric loss error variable quantity; and when the capacitance breakdown error variable quantity or the dielectric loss error variable quantity is not 0, judging that the insulation state of the CVT is abnormal, and triggering a self-repairing material feedback control mechanism. According to the invention, on-line evaluation of the internal insulation state of the CVT is realized by on-line monitoring whether the capacitor of the CVT is broken down and whether the dielectric loss is abnormally increased.

The invention relates to the technical field of brain imaging, in particular to a frequency-domain near-infrared spectrum measurement module and method and frequency-domain near-infrared spectroscopy equipment, comprising a detection unit and a processing unit, the detection unit is used for directly contacting with the head of a user, emitting detection light to a detected tissue and receiving a detection signal formed by reflection of the detected tissue, and the processing unit is used for processing the detection signal; amplitude data and phase data of the detection signal are extracted, and the amplitude data and the phase data are sent to the processing unit after analog-to-digital conversion; and the processing unit is used for calculating optical parameters of the detected tissue based on the converted amplitude data and phase data, and wirelessly transmitting the optical parameters to the target main control unit. Amplitude and phase detection functions are completed by the front-end measurement module in advance, the use of a high-speed ADC and a mixer is avoided, the system complexity is reduced, signal transmission between the measurement module and the main control unit depends on wireless communication, excessive cable connection is not needed, and the brain activity monitoring system is suitable for brain activity monitoring requirements in a dynamic scene.