58 results about "Digital demodulation" patented technology

The invention discloses a detection method of an ocean magnetic field sensor based on a diamond NV color center. The detection method comprises the following steps: S1, calibrating a base line; s2, alternately measuring fluorescence between two single quantum resonance frequencies, and obtaining a difference to realize DQ reading; s3, three-axis compensation current is adjusted based on closed-loop control, and the NV working point is maintained at zero magnetization bias; s4, obtaining background magnetic field change through digital demodulation and adaptive filtering; and S5, calculating a gradient based on the spatial difference of the multi-point light spots, judging the existence and trajectory of the underwater vehicle in combination with a threshold value and a spectrum matching method, calibrating the threshold value according to the magnetic field characteristics of the existing underwater vehicle, adopting short-time Fourier transform signal spectrum, comparing the threshold value with known submarine characteristic spectrum data, and prompting if the similarity exceeds a set threshold value. According to the detection method, the measurement precision and the anti-interference capability can be improved, and the method is suitable for real-time monitoring of weak magnetic anomalies (such as magnetic moment disturbance of an underwater vehicle).

The invention relates to the technical field of digital demodulation, in particular to a digital demodulation method suitable for deep ultraviolet light communication, which comprises the following steps of: adopting multiple delay processing with half code element width, and respectively carrying out double extraction processing on a discrete sampling signal which is not subjected to delay processing and a plurality of delay sampling signals to obtain a plurality of delay extraction signals; in this way, the key sampling time in the coverage code element period can be ensured, and a basis is provided for subsequent accurate synchronization; a plurality of delay extraction signals are respectively input into corresponding equalization processing units, a preset local training sequence is loaded to each equalization processing unit to obtain a plurality of equalization filtering signals, and the plurality of equalization filtering signals and the preset local training sequence are respectively subjected to related judgment processing, so that the inter-symbol interference is inhibited, and meanwhile, the equalization processing efficiency is improved. The synchronization signal can be quickly screened out, so that the problem that inter-symbol interference and synchronization are difficult to consider in a traditional demodulation method is solved, and the demodulation efficiency and reliability are remarkably improved.

This application relates to the field of electrical technologies, and provides a full even harmonic digital demodulation method based on full-phase analysis for a magnetic modulator. According to the full even harmonic digital demodulation method based on full-phase analysis for a magnetic modulator, standard voltage timing data output by the magnetic modulator is obtained when a DC calibration current with a set amplitude is fed into the magnetic modulator during calibration of the magnetic modulator; an output voltage sequence from full-phase Fourier analysis is established based on the standard voltage sequence data, and the output voltage sequence is preprocessed; comprehensive analysis is performed on the preprocessed output voltage sequence from full-phase Fourier analysis to obtain all standard even harmonic signals and current conversion coefficients.

The invention discloses an active pen and touch screen interaction system resistant to common-mode interference and a signal demodulation method. The system comprises a signal receiving terminal and a signal transmitting terminal. The signal transmitting terminal modulates data to be transmitted by adopting a differential binary phase shift keying modulation method, and transmits a generated modulation signal to the signal receiving terminal; the analog front-end receiving module is coupled with the signal transmitting terminal, receives the modulation signal and outputs a digital square wave signal after fidelity extraction processing; and the digital demodulation processing module performs differential coherent digital demodulation on the digital square wave signal based on the prior characteristics of the modulation signal, inhibits residual noise and recovers data to be sent. The analog front end focuses strong common-mode noise suppression and analog filtering, the digital demodulation algorithm performs secondary digital purification by using signal time sequence characteristics, and the two constructs an efficient anti-interference pipeline. Meanwhile, the regular square wave signals can be directly processed through differential coherent demodulation, and the requirements for performance and power consumption of a rear-end processor are lowered.

The present application provides a Y waveguide waveform slope measurement and compensation method to solve the problem that the existing high-precision fiber-optic gyroscope Y waveguide waveform slope measurement method is based on the characteristics of the Y waveguide itself, ignoring the error of the fiber-optic gyroscope closed loop modulation wave when resetting caused by the Y waveguide waveform slope after the Y waveguide is connected with the optical path of the fiber-optic gyroscope. The present application uses the existing optical path and circuit for testing the performance of the fiber-optic gyroscope, uploads the Y waveguide waveform slope test results to the upper computer through the circuit, and when a ±23 / 8π square wave is used as a digital demodulation circuit to apply a waveform slope trigger signal, the pressure difference of the fiber-optic gyroscope demodulation signal before and after resetting is the largest. The upper computer calculates the Y waveform slope error, compensates for the error of the fiber-optic gyroscope closed loop modulation wave when resetting, improves the gyroscope precision of the fiber-optic gyroscope at a small rate of rotation, and improves the application range of the fiber-optic gyroscope.

The invention relates to a digital demodulation method for a mining wireless electromagnetic wave scenograph, belongs to the technical field of mining electromagnetic wave detection, and aims at solving the problems that an existing scenograph depends on an analog filtering and rectifying circuit, so that the circuit is complex, and the reliability is poor. According to the method, after a receiver receives and amplifies an electromagnetic wave signal, the electromagnetic wave signal is sampled by an analog-to-digital conversion module, a field programmable logic gate array performs fast Fourier transform on a digital signal, and an amplitude corresponding to a transmitting frequency is extracted as an effective signal, so that digital demodulation is realized. Filtering and rectifying circuits do not need to be simulated, the circuit structure can be remarkably simplified, the reliability and the real-time performance of an instrument are improved, and the stable detection requirement in the mine environment is met.

A chirp multi-carrier transmission method based on windowing and truncation belongs to the field of wireless communication technology. The purpose of the present invention is to achieve efficient spectrum utilization while improving the bit error rate performance. The present invention first performs digital modulation and serial-to-parallel conversion on a random bit stream sequence, then performs a discrete Fresnel inverse transform on the conversion result, and after the discrete Fresnel inverse transform result passes through a time domain truncation window, the intercepted signal is converted into parallel and serial, and the parallel-to-serial conversion result is then sent through a channel. The receiving end performs serial-to-parallel conversion, zero padding, discrete Fresnel transformation, and inter-subcarrier interference elimination on the received signal, and then digitally demodulates the signal after interference elimination to restore the original bit stream data. The present invention saves transmission time and improves transmission efficiency by performing windowing and truncation in the time domain, and the bit error rate performance is better than that of existing systems. The method of the present invention can be applied to the field of wireless communication technology.

The invention discloses a portable human heart imaging hardware system based on bioelectrical impedance. The system comprises an excitation signal processing module, a detection signal conditioning module and a digital processing module. The excitation signal processing module adopts a DAC (Digital-to-Analog Converter) to generate an excitation signal, and after voltage amplification and band-pass filtering, the excitation signal drives an excitation electrode through an analog switch; the detection signal conditioning module switches a measuring electrode through an analog switch, a programmable instrumentation amplifier is combined with an RDAC digital potentiometer to realize self-adaptive gain adjustment of a detection signal, flexible gain of the signal is realized, and the signal is sent to an ADC after being filtered; the digital processing module carries out digital demodulation on the collected signals, extracts amplitude and phase information and then transmits the amplitude and phase information to an upper computer for image reconstruction. The flexible signal gain mechanism of the system realizes a full-custom signal gain curve, breaks through the fixed magnification gain limitation of the traditional integrated PGA, adapts to the impedance change of different individuals and experimental media, and improves the signal-to-noise ratio of the system, thereby obtaining more accurate cardiac impedance acquisition data.

The application discloses a kind of based on bimodal resonance's photoacoustic-scattering aerosol dual-wavelength synchronous detection system and method, belong to photoelectric detection technical field, in the system, dual-wavelength light source modulation module generates two different frequency modulated laser, respectively from two ends into double-difference bulb pipe coupling photoacoustic-scattering combined gas cell;The gas cell includes the two ends of two acoustical tubes arranged in parallel and each is connected with an integrating sphere, form H type coupling structure;Scattering signal collection module, photoacoustic signal acquisition and processing module respectively acquire two-channel scattering photon counting data in two integrating spheres, sound wave signal in two acoustical tubes and two integrating spheres;Digital lock-in signal processing module based on FPGA outputs modulation signal to light source, and receives sound wave signal in two acoustical tubes and two integrating spheres to carry out full-digital demodulation and processing.The application effectively solves the problem of time-space asynchronization and sampling cumulative error caused by time-sharing multiplexing or multiple machine parallel connection.

The application discloses a laser phase noise measurement method based on delay self-heterodyne and digital demodulation, and relates to the technical field of laser measurement, and comprises the following contents: after being adjusted by a variable optical attenuator, to-be-measured laser is divided into a frequency shift arm and a delay arm, the frequency shift arm is frequency-shifted by an acousto-optic modulator, the delay arm is delayed by a delay optical fiber, and original electric beat frequency signals are obtained by a balanced photoelectric detector after the two arms are coupled; homologous and synchronous quadrature demodulation is carried out on the original electric beat frequency signals, envelope credibility judgment and abnormal sample repair are combined, and a continuous differential phase sequence is obtained; actual optical time delay is determined according to the beat frequency spectrum characteristics and the continuous differential phase sequence, and a differential phase power spectral density is formed; then, transmission relationship conversion is carried out according to the actual optical time delay, bounded spectrum compensation is implemented on a zero point neighborhood and a low credibility frequency point, and an intrinsic phase noise power spectral density is obtained. The application can improve the stability, continuity and result credibility of phase noise measurement under the condition of short delay.

The application discloses a pulse high-voltage divider calibration device and method, wherein the device comprises a pulse high-voltage source, a high-voltage voltage dividing network, a high-voltage multi-node acquisition module, a high-voltage optical fiber transmission module, a high-voltage signal demodulation module, a multi-channel acquisition module and a calibration controller. The high-voltage voltage dividing network is composed of RC parallel circuits in series and is used for dividing high-voltage signals. The high-voltage multi-node acquisition module is used for measuring pulse voltage signals after voltage division. The high-voltage optical fiber transmission module comprises a fiber transmitter and a high-voltage weather-resistant single-mode optical fiber and is used for transmitting pulse voltage signals in the form of optical signals. The high-voltage signal demodulation module comprises a fiber receiver and a digital demodulator and is used for receiving and demodulating optical signals. The multi-channel acquisition module comprises a synchronous clock source, an acquisition unit and a cache unit and is used for acquiring and storing pulse voltage signals. The calibration controller is used for calculating pulse voltage signals. The application solves the problems of a complex calibration system, weak anti-electromagnetic interference and a complicated calibration process.

This application belongs to the field of lock-in amplifier technology, specifically disclosing a large dynamic range digital lock-in amplifier, comprising: a signal generator for generating sine and cosine reference signals; a DAC for performing digital-to-analog conversion on the generated reference signal and providing the converted analog quantity to the device under test (DUT); an ADC for performing analog-to-digital conversion on the signal output by the DUT and providing the converted digital amplitude to a gain controller and a digital demodulator; a gain controller for comparing the difference between the desired voltage amplitude and the digital amplitude provided by the ADC, and adjusting the amplitude of the reference signal according to a negative feedback method; and a digital demodulator for approximating the amplitude-frequency and phase-frequency characteristics of the DUT based on the reference signal and the digital amplitude provided by the ADC through a fitting method, and outputting an estimated vector. This application adjusts the amplitude of the reference signal according to a negative feedback method to avoid the signal link entering the nonlinear region, thus achieving a large dynamic range.

The invention provides a digital demodulation type quartz MEMS tuning fork trimming device, and belongs to the field of MEMS tuning fork trimming. The device comprises an upper computer and a quartz MEMS tuning fork which are respectively connected with a first controller and a second controller. The upper computer is used for sending a first driving command to the first controller and sending a second driving command and a third driving command to the second controller; the second controller is used for controlling the quartz MEMS tuning fork to work in a gyro function mode according to the second driving command and the first parameter when a driving end mass block of the quartz MEMS tuning fork is roughly repaired; and the fine trimming module is used for performing linear frequency sweeping on the quartz MEMS tuning fork according to the third driving command during fine trimming to obtain a target mechanical orthogonal item, and determining that fine trimming of the driving end mass block is completed when the target mechanical orthogonal item reaches the standard. The trimming efficiency and precision can be considered through double-stage trimming and automatic control, and meanwhile the trimming cost is reduced.

The present invention provides a receiving device and a receiving method that can obtain an appropriate RSSI value corresponding to the signal quality of the actual received signal received by the antenna. [Solution] The receiving device and receiving method include an RSSI detection unit 13 in the receiving high-frequency unit 10 that detects a detected RSSI value from the input received signal, a signal quality level calculation unit 23 in the receiving control unit 20 that calculates the signal quality level from the received signal digitally demodulated by the digital demodulation unit 21, a virtual RSSI conversion unit 24 that converts it into a virtual RSSI value corresponding to the signal quality of the actual received signal received by the antenna, and an RSSI output display unit 25 that displays the virtual RSSI value and the detected RSSI value.

The present invention discloses a precise temperature measurement and control device based on a pre - placed AC bridge. The device includes a temperature control and temperature fluctuation measurement module, an actuator driving module, and a controlled object module. Aiming at improving the temperature control accuracy and temperature stability of the temperature measurement and control device, an AC Wheatstone bridge and a subsequent digital demodulation link are adopted to reduce the noise of the front - end amplifier. Additionally, the entire Wheatstone bridge is uniquely moved to the controlled object end, and the temperature fluctuation measurement circuit and the temperature control circuit are placed on the same circuit board. This temperature measurement and control device has higher temperature control accuracy, greatly improves the stability and anti - interference ability of the system, reduces the residual temperature noise after the temperature control system operates stably in a closed - loop manner, and thus improves the temperature stability of the temperature measurement and control device after temperature control.

The invention relates to an intelligent microbial electrode impedance analysis device, which belongs to the technical field of electrochemical impedance spectroscopy analysis, and comprises a three-electrode system used for collecting microbial impedance signals; the response signal acquisition and conditioning module is used for preprocessing the acquired microbial impedance signal; the self-adaptive digital phase-locked amplification module adopts a synchronous orthogonal digital demodulation technology and utilizes known excitation signal digital phase information to generate an orthogonal reference signal, extract amplitude and phase information of an impedance response signal, perform self-adaptive noise suppression and decouple core parameters; the reinforcement learning optimization unit is used for evaluating a current measurement state and selecting a next frequency step length; the self-adaptive excitation module is used for generating a sine excitation voltage signal and outputting the sine excitation voltage signal to the three-electrode system; and the data display module is used for displaying the impedance spectrum and the Rct curve.

The present invention discloses a low-noise dual-output synchronous demodulation circuit and method. The synchronous demodulation circuit includes a signal source to be measured, a reference signal source, a pulse generator, a voltage comparator, a logic operator, a reversible counter, a digital-to-analog converter, a digital filter, and an analog filter. A sinusoidal reference signal is generated by the pulse generator as a digital pulse signal. A sinusoidal voltage signal is generated by the voltage comparator and the logic operator as a synchronized pulse count signal. The reversible counter and the digital-to-analog converter are used to obtain a digital voltage signal and an analog voltage signal. Real-time looping is used to maintain the consistency of the voltage value of the sinusoidal voltage signal when the analog voltage signal is synchronized with the digital pulse signal. This synchronous demodulation method can effectively reduce high-frequency components and improve the signal-to-noise ratio of the demodulated signal. The synchronous demodulation circuit can directly provide dual outputs of a digital demodulation signal and an analog demodulation signal.

The invention relates to a PID parameter adaptive adjustment method and system, electronic equipment and a readable medium, and the method comprises the steps: outputting an analog voltage signal corresponding to an expected gradient waveform to a gradient amplifier through a gradient output module, so as to form an actual current corresponding to the analog voltage signal through the gradient amplifier; a voltage feedback signal which is output by the gradient amplifier and corresponds to the actual current is transmitted to the spectrometer radio frequency module; performing amplitude modulation and frequency mixing on the voltage feedback signal through a spectrometer radio frequency module to obtain a frequency mixing signal; digital sampling and digital demodulation are carried out on the frequency mixing signal through an optical fiber box, and an actually measured gradient waveform is obtained; and calculating a time domain error between the expected gradient waveform and the actually measured gradient waveform, and under the condition that the time domain error is greater than a target error, adaptively adjusting the PID parameter according to the error type of the actually measured gradient waveform until the time domain error is less than the target error. The problem that the PID parameters of the gradient amplifier are difficult to adaptively calibrate accurately is solved.

This invention discloses a low-power analog front-end circuit and control method for animal tags. The circuit includes: a radio frequency (RF) unit, a power management unit, and an antenna. The power management unit includes a rectifier and a low-power power management circuit. The rectifier is connected to the antenna. The low-power power management circuit supplies power to the RF unit and digital circuits. The RF unit includes a load modulation and limiting circuit, a demodulation circuit, and a clock generation circuit. The demodulation circuit receives the demodulated envelope signal sent by the rectifier and outputs digital demodulated data to the digital circuits. The clock generation circuit extracts a clock signal from the antenna signal generated by the antenna and outputs the clock signal to the digital circuits. The load modulation and limiting circuit receives the limiting reference voltage sent by the rectifier and the uplink data output by the digital circuits. In this embodiment, an animal identification tag adapted for wireless communication achieves a balance between low power consumption and small area while ensuring communication reliability.

The present invention relates to an MF-TDMA frequency hopping anti-interference system based on secondary interference judgment. The method includes an AD sampling unit, a digital branch filtering unit, a power estimation and secondary interference judgment unit, and a digital demodulation unit. Combining the characteristics of the MF-TDMA system, the method performs power estimation after AD sampling and power estimation after digital branch filtering on multi-carrier signals. The method utilizes the two power estimates combined with secondary interference judgment to accurately detect and identify interference. Furthermore, based on a joint discrimination flag, the method determines whether the signal participates in timing error calculation and data interpolation. Furthermore, the method scales the useful signal through digital forward automatic gain control (AGC). This method can effectively counteract the effects of narrowband interference on a multi-mode, multi-carrier frequency hopping anti-interference communication system.

The invention discloses a novel radio station based on voice recognition and translation, which is characterized in that voice recognition is carried out on the voice of a sender to generate corresponding language coding information, the information is modulated by a digital modulation module and then forms a radio frequency signal through a frequency mixing amplification module, and the radio frequency signal is transmitted to the air through an antenna; after receiving a radio frequency signal through an antenna, the receiving station generates an intermediate frequency digital modulation signal through a frequency mixing amplification module, then demodulates the intermediate frequency digital modulation signal into language coding information of a speaker of the transmitting station through a digital demodulation module, and forms language digital voice information corresponding to a listener of the receiving station after the language coding information is processed by a voice translation module in a voice processing module. The digital-to-analog signal conversion is realized through the D / A conversion module, the analog signal is sent to the earphone through the power amplification module to form a voice message which can be understood by a receiver, the occupied bandwidth is far smaller than that of a traditional radio station, and meanwhile, barrier-free cross-language communication can be realized.

The invention discloses a magnetic encoder, and the encoder comprises a magnetic sensor which is used for generating an amplitude modulation signal in a rotating magnetic field under the drive of a high-frequency AC signal; the two magnetic switch elements generate orthogonal pulse signals with phase difference in the rotating magnetic field, and the orthogonal pulse signals serve as additional quadrants; the signal processing unit is used for generating a high-frequency alternating current signal; signal processing is carried out on the amplitude modulation signal output by the magnetic sensor to obtain a digital demodulation signal, and the signal processing sequentially comprises differential-to-single-ended processing, amplification processing, high-pass filtering processing and demodulation processing; position information is calculated based on the digital demodulation signal and the additional quadrant. The magnetic encoder provided by the invention improves the resolution of the rotation angle of the rotor.

The invention relates to the technical field of microwave and millimeter wave imaging, in particular to a microwave and millimeter wave sparse array wavenumber domain algorithm combined compressed sensing imaging method and system. According to the technical scheme, the method comprises the following steps: obtaining a backscattering echo signal from a target, and carrying out digital down-conversion processing to obtain a digital IQ demodulation signal; according to the method, the wavenumber domain algorithm and the compressed sensing technology are combined in a cross-dimension mode, efficient focusing and data decoupling are achieved through the wavenumber domain algorithm in the motion scanning dimension, high-quality reconstruction is conducted through the compressed sensing algorithm in the array-distance dimension, and therefore image sidelobes are remarkably restrained, the imaging quality is improved, and meanwhile the image quality is improved. The dimension and calculation complexity of the sensing matrix are greatly reduced, the algorithm efficiency and practicability are improved, and the method can flexibly adapt to various sparse array configurations such as straight lines, broken lines and arc lines.

The present invention discloses a method and device for demodulating an RF signal to polar in-phase and quadrature ( IQ) components in a wearable device that monitors vital functions of a user. The method includes receiving the RF signal through an instrumentational amplifier and processing output signals from the amplifier for sequentially extracting the I signals and the Q signals with a 90 ° delay between the extraction of I signals and Q signals. The device comprises a logical circuit configured to receive RF input signals, process the input signals using a logical operation, and provide output signals based on the logical operation. The digital I / Q demodulation is achieved using a SINC filter, a deltasigma modulator, and a digital filter with bandwidth larger than the modulated signal frequency. The wearable device ' s clock is used as a base signal for the digital I / Q demodulator. This invention offers a novel, cost-effective, and efficient solution for monitoring vital functions in wearable devices.

The invention belongs to the technical field of river monitoring, and provides a signal real-time processing method for an ultrahigh-frequency river detection radar, and the method comprises the steps: S1, generating a radar transmitting signal through a transmitting circuit; s2, a receiving circuit receives radar echo signals reflected by the surface of the river; s3, in the FPGA, carrying out direct radio frequency band-pass sampling on the digital signal, carrying out digital frequency mixing on the digital signal and a local oscillator signal, and then obtaining a low-frequency digital demodulation signal through a CIC filter; according to the method, the linear sweep frequency interrupt continuous wave (FMICW) is adopted as a radar transmitting signal, and the specific center frequency, bandwidth and sweep frequency period are combined, so that efficient detection of the river surface is realized; meanwhile, the real-time performance, the accuracy and the stability of signal processing are remarkably improved by utilizing high-quality radar transmitting signals, an optimized receiving antenna array design, an efficient digital signal processing flow and an advanced spectral analysis and direction-of-arrival estimation algorithm, so that the flow condition of a river can be monitored in real time.

The present invention discloses an on-orbit measurement method for a GEOSAR antenna pattern, comprising the following steps: step 1, arranging calibration equipment; step 2, formulating a satellite observation plan; step 3, performing IQ digital demodulation on the signal collected by the calibrator to generate a baseband complex signal; step 4, performing pulse compression processing on the baseband complex signal generated in step 3, and extracting the peak amplitude of each pulse; step 5, reading satellite precise orbit determination parameters and satellite attitude measurement parameters, and converting the satellite orbit coordinate system E into the satellite attitude measurement system E according to the satellite attitude conversion sequence. b Convert to the satellite body coordinate system E s Then, the azimuth angle corresponding to each pulse is calculated. In step 6, the azimuth angle corresponding to each pulse calculated in step 5 is compared with the peak amplitude of each pulse extracted in step 4 to obtain the GEOSAR antenna pattern. The method of the present invention is simple in terms of ground equipment requirements and is highly practical. It is an effective and feasible method for on-orbit measurement of GEOSAR antenna patterns.

This invention provides a coherent acquisition platform with a full-dimensional mismatch self-correction time-interleaved ADC system, belonging to the field of mismatch self-correction technology. The architecture includes an analog front-end conditioning module, a time-interleaved ADC sampling array, a clock synchronization distribution module, a full-dimensional mismatch self-correction module, and a high-speed data transmission module. The ADC sampling array employs an interleaved structure with multiple main channels and multiple sub-ADCs per channel, achieving ultra-high-speed synchronous acquisition of multiple coherent signals. The full-dimensional mismatch self-correction module pioneers a dual-mode detection mechanism of "calibration sequence injection + blind estimation," which can detect and correct four types of mismatches—gain, delay, bias, and bandwidth—between sub-ADCs in real time, balancing initial calibration accuracy with dynamic environmental adaptability. This invention has advantages such as high sampling rate, good synchronization, excellent mismatch suppression effect, and strong signal integrity, and can be directly used in coherent acquisition equipment with speeds of 100G and above, providing high-quality signals for subsequent digital demodulation.

This invention relates to the field of digital signal communication technology and discloses a DBPSK digital demodulation method based on the principle of baseband signal envelope phase tracking, comprising the following steps: S1: capturing the DBPSK modulated signal; S2: performing digital down-conversion processing on the DBPSK modulated signal to obtain the I-channel baseband signal envelope and the Q-channel baseband signal envelope; S3: comparing the amplitudes of the I-channel and Q-channel baseband signal envelopes and selecting the baseband signal envelope with the larger amplitude as the demodulation basis; S4: based on the correlation between the demodulation basis and the original information symbols, outputting a binary symbol sequence that maintains a fixed correspondence with the original information symbols. This invention can perform digital demodulation and obtain a binary symbol sequence after capturing a valid DBPSK modulated signal, can adapt to most Doppler frequency shift ranges in engineering applications, occupies and consumes few resources, and has good portability.

To provide a method for digital demodulation of all even harmonics of a magnetic modulator based on full phase analysis.SOLUTION: According to the digital demodulation method for all even-order harmonics of a magnetic modulator based on full-phase analysis, when the magnetic modulator is calibrated, standard voltage time sequence data output by the magnetic modulator when a direct current calibration current of a set value flows through the magnetic modulator is obtained, an output voltage sequence of full-phase Fourier analysis is established and pre-processed according to the standard voltage time sequence data, and the pre-processed output voltage sequence of full-phase Fourier analysis is comprehensively analyzed to obtain standard even-order harmonic signals and current conversion coefficients of each order. The present invention uses the full-phase Fourier analysis technology to perform comprehensive pre-processing and comprehensive analysis on the output voltage signal of the air modulator, which greatly reduces the problems of spectrum leakage and phase disturbance, so that the data sampled at different time points are fully utilized, and the signal processing is more accurate.SELECTED DRAWING: Figure 1

An analog-to-digital converter (ADC) circuit (200) is provided, designed to process an input signal. The ADC circuit (200) includes a modulation circuit (210) designed to modulate the input signal with a modulation frequency to generate a modulated signal. The ADC circuit (200) includes a combination circuit (206) designed to receive the modulated signal and combine it with a feedback signal (208) to generate a combined signal. The ADC circuit (200) includes a conversion circuit (220) designed to convert the combined signal into a digital signal at a sampling frequency. The ADC circuit (200) includes a tracking register (230) designed to store and update the digital signal.The ADC circuit (200) includes a prediction circuit (240) designed to estimate a future value of the digital signal based on historical data from the digital signal and to load the estimated value into the tracking register (230) at a modulation transition time. The ADC circuit (200) includes a feedback circuit (250) designed to convert a digital output signal from the tracking register into the feedback signal provided to the combination circuit. The ADC circuit (200) includes a demodulation circuit (260) designed to demodulate the digital signal at the modulation frequency to produce a digital demodulated output signal.