73 results about "Differential modulation" patented technology

The invention relates to the technical field of electrical digital data processing, and discloses a lightweight-based multi-modal data enhancement method, which comprises the following steps: acquiring a multi-modal feature tensor; extracting a vector orthogonal projection scalar and determining the novelty; updating the global covariance matrix when the novelty is greater than a redundancy threshold, and maintaining the global covariance matrix in a register state when the novelty is not greater than the redundancy threshold; extracting a main diagonal variance component to determine a differential modulation coefficient; calculating a second-order moment manifold projection operator according to the global covariance matrix, and calibrating the operator by using a differential modulation coefficient; the calibrated operator is used for carrying out orthogonal projection on random noise to generate a structured disturbance vector, the structured disturbance vector is superposed to a multi-modal feature tensor to output enhanced features, a novelty judgment mechanism is used for restraining statistical deviation caused by steady-state redundant data, computing resource occupation is reduced, and it is ensured that semantic alignment between modals is maintained in enhanced feature distribution.

The invention discloses a diffraction neural network optical classification method and system based on dual-wavelength differential modulation, and relates to the technical field of optical calculation and optical information processing, and the method comprises the steps: S1, optimizing the phase distribution of a single diffraction layer through a deep learning back propagation algorithm; s2, loading a code corresponding to the input information through an input layer; s3, introducing two coherent light sources with different wavelengths to irradiate the codes in sequence or in parallel; s4, after the single diffraction layer modulates the input light field, an output light field is detected through a detector; and S5, performing differential normalization operation on the light intensities of different wavelengths to obtain a discrimination signal Sc of each category, and completing optical classification. According to the invention, the adjustment error caused by a multilayer device is eliminated through a single-layer diffraction structure, a dual-wavelength differential detection mechanism is introduced, and the non-negativity limitation of a light intensity signal is broken through, so that the classification precision and robustness are remarkably improved while the structure simplification is ensured, and the method has important engineering value and application prospect.

The invention relates to a heterogeneous diffraction optical waveguide which comprises at least two waveguide units arranged in a stacked mode, and each waveguide unit comprises an optical waveguide sheet and a grating structure arranged on the surface of the optical waveguide sheet. At least one structural parameter of the optical waveguide sheets in the at least two waveguide units is modulated, and the structural parameters of the grating structures are the same, so that diffraction efficiency difference modulation of visible light in the FOV range of 50-70 degrees in the at least two waveguide units is completed. The invention has the advantages of lower cost, shorter processing period, lighter weight and higher red light efficiency.

The present invention discloses a high-precision and low-power AC impedance measurement circuit and method. The circuit includes: a waveform generator; a first isolation buffer, whose positive input terminal is connected to the sine wave signal output terminal; a switching circuit, which is connected to the negative input terminal and the output terminal of the first isolation buffer; a to-be-measured impedance and a reference impedance, which are connected to the switching circuit; an operational amplifier, whose positive input terminal is connected to a reference voltage, and whose negative input terminal is connected to the to-be-measured impedance and the reference impedance; a sampling impedance, which is connected between the negative input terminal and the output terminal of the operational amplifier; a first selection switch, which is connected between a second isolation buffer and the to-be-measured impedance or the reference impedance; a second selection switch, which is connected between a third isolation buffer and the operational amplifier; a fully differential I / Q modulation rectifier, which is used for rectifying the received signal; a low-pass filter; an analog-to-digital converter; and an MCU / DSP module, which is used for calculating the modulus value and the phase angle of the to-be-measured impedance. The present invention can improve the measurement accuracy of the to-be-measured impedance and reduce the power consumption.

The optical module provided by the utility model comprises a circuit board, a laser chip and a substrate. The substrate is used for bearing the laser chip. The surface of the substrate is provided with a first differential signal transmission line and a second differential signal transmission line, and the first differential signal transmission line and the second differential signal transmission line transmit a first differential modulation signal and a second differential modulation signal to the laser chip respectively. The second differential signal transmission line is far away from the laser chip relative to the first differential signal transmission line. The first differential signal transmission line comprises a first guiding part and a first bending part. And in the transmission direction of the first differential modulation signal, the first guide part is gradually far away from the laser chip to guide the first differential signal transmission line to extend towards the direction far away from the laser chip so as to provide a bending space for the first bending part. The second differential signal transmission line comprises a second guiding part and a second bending part, and the second guiding part is gradually close to the laser chip, so that the differential impedance discontinuity is reduced. The curvature radius of the first bending part is larger than that of the second bending part, thereby counteracting the path length difference of the transmission line, reducing the phase difference, and improving the high-frequency performance.

The invention relates to the technical field of isolated transmission, and discloses a data transmission performance optimization circuit, a demodulation device and a digital isolator, the demodulation device is suitable for generating a first demodulation signal and a second demodulation signal in the process of demodulating a differential modulation signal, and the data transmission performance optimization circuit comprises a detection unit, a processing unit and a processing unit, the detection unit is configured to detect at least one of the differential modulation signals so as to determine the carrier state of the differential modulation signals; and the signal adjusting unit is configured to adjust at least one of the first demodulation signal and the second demodulation signal according to the carrier state, so that the absolute value of the voltage difference value between the first demodulation signal and the second demodulation signal is reduced in the carrier state switching process of the differential modulation signal. According to the invention, the dynamic adjustment of the digital isolator on the PD index is realized, so that the performance optimization effect of the digital isolator is comprehensively improved, and the signal transmission performance is greatly improved.

This invention discloses a monotonic magnetic ring dual-rotor radial-axis composite modulation magnetic gear. The magnetic gear includes an inner rotor yoke, an inner rotor permanent magnet, a tuning ring, an outer rotor permanent magnet, and an outer rotor yoke. The inner rotor yoke and the inner rotor permanent magnet constitute the inner rotor, and the outer rotor permanent magnet and the outer rotor yoke constitute the outer rotor. The inner and outer rotors are coaxially arranged to form a dual-rotor structure, capable of relative rotation. The tuning ring, a single tuning structure, is positioned between the inner and outer rotors to simultaneously achieve radial modulation and axial differential modulation, thus forming a radial-axis dual-modulation magnetic gear. Both the inner and outer rotor permanent magnets employ an asymmetric Halbach array structure. This application achieves radial modulation and differential modulation, constructing a radial-axis coupled dual-modulation magnetic field structure, improving magnetic field utilization and torque transmission capability.

The present application relates to a kind of pixel depth of field determination method and determining unit, three-dimensional reconstruction method and system, electronic equipment, computer readable storage medium, the determination method includes the steps: after the transmission of stripe image by telecentric lens, half-transmission half-reflection mirror is projected to the surface of measured object, by the reflection of telecentric zoom lens, half-transmission half-reflection mirror is respectively measured object reflected projection image is collected under two different focal distances;Afterwards, according to several real images under each focal length, the corresponding measured modulation is calculated respectively, two measured modulation is subtracted to obtain measured differential modulation, measured differential modulation is in the corresponding depth of field-differential modulation relationship corresponding depth of field as the actual depth of field of to-be-determined pixel, wherein, depth of field-differential modulation relationship is obtained by calibration step.Using the method of the present application can obtain more accurate depth of field, improve the effect of three-dimensional reconstruction.

The application belongs to the technical field of wireless communication, and discloses a backscattering communication method, device and system based on multi-carrier differential modulation t The transmission vector at t-1 time is expanded into a symmetric and full-rank subcarrier block transmission matrix, the transmission vector u t is subjected to rectangular differential modulation to obtain the transmission vector at t time, and then is converted into a time-domain data frame and mapped into a reflection coefficient; and the excitation source signal is modulated by means of an impedance network to generate a backscattering signal. Since differential modulation transmits information based on the difference between adjacent symbols, the channel state information is cancelled in the process of data detection at the receiving end, and the original sending data can be recovered by non-coherent detection of the receiving signal at the receiving end, without a complex cascaded channel estimation process, so that the complexity of the multi-carrier backscattering communication system is effectively reduced.

The invention discloses a high-speed modulation and demodulation method for a dynamic underwater acoustic network, and the method also employs an orthogonal sequence multiplexing modulation and demodulation technology based on a Zadoff-Chu (ZC) sequence, and combines the setting of a cyclic displacement interval to construct a plurality of sub-channels, thereby achieving the multi-path separation, and reducing the average transmitting power of a system at the same time. In the aspect of multi-user access, interference among multiple users is regarded as additive white noise by using quasi-orthogonal characteristics among different ZC root sequences, so that uncoordinated random concurrent access is supported; differential modulation between sub-channels in a symbol is adopted, and the requirement for phase tracking is lowered; and a receiving end converts multipath amplitude information into soft decision information through cyclic correlation spectrum calculation and multipath diversity technologies, so that the calculation complexity is reduced, and the throughput of the time-varying underwater acoustic system is improved while the multi-user access efficiency is improved.

This invention discloses a trace oxygen sampling control method, including: calculating the complex impedance modulus, phase angle, and time derivative based on real and imaginary impedance data; obtaining the double-layer perturbation index by weighted fusion of the impedance change rate and phase stability factor; adaptively determining the pressure fluctuation amplitude based on the double-layer perturbation index to protect sensor stability and improve replacement efficiency; and generating a micro-pressure differential modulation control parameter based on the pressure fluctuation amplitude. This invention solves the technical problem of traditional fixed-parameter control methods that cannot balance sensor protection and rapid response, and achieves intelligent and precise control of the trace oxygen sampling process.

Methods, systems, and devices for wireless communications are described. A wireless device, such as an Ambient Internet of Things (AIoT) device may transmit a first signal to a reader device via a device to reader (D2R) communication link. The first signal may include one or more reference signal pilots. The wireless device may receive, via a reader to device (R2D) communication link, an indication from the reader device to configure a combined modulation and reference signal pilot scheme. In response to receiving the indication, the wireless device may transmit a second signal to the reader device via the D2R communication link. The second signal may be configured in accordance with the combined modulation and reference signal pilot scheme.

The invention provides an optical waveguide element capable of suppressing phase deviation of a differential modulation signal transmitted through an electrode. An optical waveguide element in which two modulation electrodes (E1, E2) for applying a differential modulation signal are disposed on each of two branch waveguides (10) constituting a Mach-Zehnder optical waveguide, each of the modulation electrodes is composed of a plurality of proximity electrodes (PE11-PE22) disposed in a divided manner along the branch waveguide, signal electrodes (LE1, LE2) for transmitting the modulation signal, and bypass electrodes (BE1, BE2) for connecting the proximity electrodes and the signal electrodes, and ground electrodes (G1, G2) are disposed so as to sandwich the two modulation electrodes. A capacity adjustment mechanism (LET11-LET12) for adjusting the phase velocity of a modulation signal transmitted through the modulation electrode is provided between the modulation electrode (E1) and the ground electrode (G1) that are adjacent to each other.

This invention discloses a fiber optic hydrophone system based on differential weak-value amplification and PGC arctangent demodulation, comprising: a pre-selection state preparation module, a phase carrier modulation module, a weakly coupled sensing module, a post-selection dual-channel module, and a demodulation algorithm implementation module. The pre-selection state preparation module outputs a pre-selected polarized beam; the phase carrier modulation module applies carrier modulation to the beam; the weakly coupled sensing module converts the sound pressure signal into the phase difference to be measured between two orthogonal polarization components; the post-selection dual-channel module has first and second channels with opposite positive and negative post-selection angles, outputting two light intensity signals; the demodulation algorithm implementation module differentially divides, mixes, and filters the two signals to generate equal-amplitude orthogonal signals, which are then arctangented to obtain the phase to be measured. This invention suppresses common-mode noise, reduces equivalent noise pressure, suppresses light intensity fluctuations and post-selection angle drift through positive and negative symmetrical dual-channel differential modulation, relaxes approximation condition dependence, broadens the applicable range, and improves signal-to-noise ratio and stability.

A differential Δ-Σ modulator includes an integrator (49) comprising a pair of single-ended amplifiers (46, 47). The differential Δ-Σ modulator includes a sampling clock (50) that drives a first switchable capacitor configuration (31) and a second switchable capacitor configuration (32) at predetermined switching cycles. The second switchable capacitor configuration (32) is adapted to sample the corresponding outputs from the pair of single-ended amplifiers (46, 47) across a pair of output sampling capacitors (C3, C5) in a first portion (P1) of the switching cycle, and to charge a common-mode capacitor (C4) with the average voltage of the voltages sampled by the pair of output sampling capacitors (C3, C5) in a second portion (P2) of the switching cycle. The voltage across the common-mode capacitor (C4) represents the common-mode voltage of the integrator (49).

An airflow generating device includes a first unit disposed in a first region and a second unit disposed in a second region. The first unit and the second unit are correspondingly disposed. The first unit generates a first air pressure having a first polarity in the first region, and the second unit generates a second air pressure having a second polarity in the second region. The second polarity is opposite to the first polarity. At least one of the first unit and the second unit includes a membrane structure, the membrane structure including a pair of flaps, the flap pair including a first flap and a second flap opposite to each other. The flap pair has an initial deflection difference or exhibits an average displacement difference between the first flap and the second flap. The flap pair operates at an ultrasonic frequency, causing the airflow generating device to generate a plurality of air pulses at an ultrasonic pulse rate.

Disclosed is a video encoding and decoding technology using a differential modulation technique for a residual signal in order to enhance compression performance in a transform skip mode. The differential modulation technique is applicable to both luma and chroma components as long as the chroma format is not monochrome (i.e. as long as chroma_format_idc=0 is not true).

The invention relates to the technical field of analog integrated circuits, in particular to a novel low-delay demodulation circuit and system.The constant current generated by a voltage source module is copied to a differential demodulation module through a first current mirror module, so that when an original modulation signal is converted into a non-input signal from an input signal, the constant current is converted into the differential demodulation module; the voltage of the differential demodulation module can be quickly discharged through the first current mirror module, so that the output original signal can be quickly reversed according to the conversion of the differential modulation signal, and the time delay of converting the high-level output into the low-level output after the demodulation circuit is converted is remarkably reduced. Meanwhile, the first current mirror module assists the differential demodulation module to perform voltage discharge, so that the differential demodulation module can improve the amplification capability of the input original modulation signal and obtain the differential modulation signal with higher amplitude and better quality without generating negative influence on the demodulation rate; and the time delay of converting the demodulation circuit from low-level output to high-level output is obviously reduced.

The invention relates to the field of optical precision measurement, and discloses a method for simultaneously measuring film thickness and optical constants based on a surface plasma resonance holographic microscopy system. When surface plasmon resonance occurs in the structure with the film attached to the surface of the metal film, the thickness and the optical constant of the film above the metal film have a differential modulation effect on a reflection phase curve near a resonance angle. And performing parameter inversion on a theoretical resonance curve calculated based on a multilayer film reflection theory and a reflected light wave phase difference under different incident angles measured by using a surface plasma resonance holographic microscopy system to realize simultaneous measurement of the film thickness and the optical constant.

An airflow generating device includes a first cell, disposed within a first region and a second cell, disposed within a second region. The first cell generates a first air pressure with a first polarity in the first region and the second cell generates a second air pressure with a second polarity in the second region. The second polarity is opposite to the first polarity. One of the first and second cells includes a film structure, which includes a flap pair. The flap pair includes a first flap and a second flap opposite to each other. The flap pair possesses an initial deflection difference or exhibits an average displacement difference between the first flap and the second flap. The flap pair operates at an ultrasonic frequency, such that the airflow generating device produces a plurality of air pulses at an ultrasonic pulse rate.

The invention discloses a quick single-pixel imaging method based on galvanometer scanning. The quick single-pixel imaging method comprises the following steps: slicing and reconstructing a Hadamard matrix to obtain an innovative scanning base graph; a galvanometer is used for continuously and rapidly scanning and traversing the modulation process of a target image, and the number of mask patterns needing to be modulated is reduced; obtaining a Hadamard coefficient of each scanning base image based on a differential measurement mode, including obtaining a light intensity value after differential modulation by using a positive Hadamard scanning base image and a negative Hadamard scanning base image, and calculating to obtain a Hadamard coefficient of the target image; and after the Hadamard coefficient of the target image is obtained, forming a Hadamard frequency spectrum, and performing inverse transformation on the Hadamard frequency spectrum to obtain a reconstructed target image. According to the invention, the problems of a large number of modulation masks and large memory consumption in the traditional single-pixel imaging technology are solved, the generation duration and imaging time of the mask pattern are shortened, and the application prospect of the single-pixel imaging technology is expanded, especially in the fields of industrial part detection, medical imaging and the like.

The invention relates to an uplink LoRa adaptive transmission method based on RIS differential index modulation, and the method comprises the steps: introducing RIS and IM into the uplink transmission of LoRa, and carrying out the differential modulation of a joint IM entity in a space-time domain. The RIS is deployed near the LoRa node as part of a transmitter, and additional information is communicated by building RIS space-time blocks, thereby enhancing the uplink transmission link of the single antenna LoRa node with the gateway. Meanwhile, in order to further improve the performance of the system, an adaptive spreading factor (SF) selection strategy is introduced. According to the invention, under the design based on the RIS differential IM, the CSI demand is effectively eliminated, and the LoRa transmission rate is significantly improved.

The invention discloses a protein gelation state differential modulation spectrum detection method, a sauce marinated product cooling method and an intelligent cooling system, and belongs to the technical field of food processing nondestructive detection and control. The method comprises the steps that near-infrared light beams with the wavelength range of 1000-2500nm are incident to a sample, meanwhile, low-frequency ultrasonic waves with the frequency of 20-100kHz are applied to the sample, the ultrasonic waves work in a pulse mode, and the pulse period and the spectrum collection period are synchronously locked; s2, phase-locked detection: adopting a phase-locked amplifier, taking the ultrasonic frequency as a reference signal, extracting a modulation component with the same frequency as the ultrasonic from the transmitted or reflected light signal, and obtaining a real part delta A '(lambda) and an imaginary part delta A' '(lambda) of a differential modulation spectrum. According to the method, the formation conditions of the hydrophobic-dominated and hydrogen-bond-dominated gels are accurately controlled, so that the quality of the sauced and marinated product is remarkably improved.

The utility model discloses a coding outer timing system signal generation circuit and a tool, the coding outer timing system tool comprises a coding outer timing system signal generation circuit, the exterior of the coding outer timing system signal generation circuit is provided with a housing, and the housing is provided with a display screen, a regulation and control button and a circuit port connector; the encodable outer timing signal generation circuit comprises an external signal input circuit, an encodable chip circuit, a signal modulation circuit and a power supply circuit, the power supply circuit is connected with an external power supply to supply power to the whole circuit, and an external signal is input to an encodable chip through the external signal input circuit; the coding chip respectively outputs a differential modulation signal and a first single-ended modulation signal to the signal modulation circuit, and finally the signal modulation circuit outputs a standard differential signal and a single-ended signal. According to the utility model, the authenticity of a signal source simulation test signal is improved, and compared with a common signal generator, the signal generator has a larger pulse width modulation range, is more convenient to carry, has a clearer operation interface, and is lower in cost.

The invention belongs to the related technical field of wireless communication, and discloses a backscatter communication method, device and system based on multicarrier differential modulation, and the method comprises the steps: modulating binary bit data to generate a transmission vector ut when a backscatter signal is transmitted; a transmission vector at the t-1 moment is expanded into a symmetrical and full-rank subcarrier block transmission matrix, a transmission vector ut is subjected to rectangular differential modulation to obtain a transmission vector at the t moment, and the transmission vector at the t moment is converted into a time domain data frame and then mapped into a reflection coefficient; the excitation source signal is modulated by means of an impedance network to generate a backscattering signal. Since the differential modulation transmits information based on the difference between adjacent symbols, the channel state information is counteracted in the data detection process of the receiving end, the receiving end can recover the original sending data by performing incoherent detection on the received signal, a complex cascade channel estimation process is not needed, and the data transmission efficiency is improved. And the complexity of the multi-carrier backscatter communication system is effectively reduced.

The utility model provides an optical waveguide element, an optical modulator and an optical transmitting device which can restrain phase deviation of differential modulation signals transmitted in electrodes. An optical waveguide element in which an optical waveguide including at least one Mach-Zehnder type optical waveguide is formed on a substrate, and in which two modulation electrodes for applying differential modulation signals are disposed for each of two branch waveguides constituting the Mach-Zehnder type optical waveguide. Each of the modulation electrodes is composed of a plurality of proximity electrodes disposed in a divided manner along the branch waveguide, a signal electrode for transmitting the modulation signal, and a bypass electrode for connecting the proximity electrodes and the signal electrode. At least one of the two modulation electrodes is provided with a capacity adjustment mechanism for adjusting the phase velocity of a modulation signal transmitted through the modulation electrode.

The application provides a frequency domain differential modulation method, system and storage medium for high-reliability and low-latency mobile communication, the frequency domain differential modulation method comprising: step 1: converting B-bit information bits into J-bit coded bits; step 2: mapping the J-bit coded bits into an M-order phase shift keying symbol block, and using a frequency domain differential modulation technology to express information as a phase difference between two adjacent subcarrier signals in the same OFDM symbol; step 3: performing K-point inverse discrete Fourier transform to convert a frequency domain transmission sequence into a time domain transmission sequence, and adding a cyclic prefix in the time domain transmission sequence; step 4: a receiver receives a serial sequence, performs K-point discrete Fourier transform, detects data by comparing subcarrier signals on the same OFDM symbol, and converts the data into B-bit information bits by using a phase shift keying soft demodulator and a channel decoder. The application has the beneficial effect that high-reliability and low-latency mobile communication can be realized at extremely low signaling cost and wireless resources.

A method, backscattering device and network nodes for differential modulation and demodulation for backscatter radio are disclosed. According to one aspect, a method in a backscattering device includes receiving an orthogonal frequency division multiplexed, OFDM, signal in a first radio frequency channel from the network node. The method includes frequency shifting the received OFDM signal to a second radio frequency channel different from the first radio frequency channel. The method further includes reflecting the frequency shifted received OFDM signal. The method also includes synchronizing reflecting of the frequency shifted received OFDM signal to an OFDM time grid.

The application discloses a kind of simultaneous differential and phase diversity photonic time stretching systems of dual polarization modulation.The system realizes differential modulation by X and Y polarization state in a single dual polarization quadrature amplitude modulator, and realizes phase diversity by using two dual polarization quadrature amplitude modulators respectively arranged at different bias operating points.The system comprises a pulse generation module, a signal modulation module, a polarization separation module and a data processing module.The pulse generation module generates pre-chirped optical pulses.The signal modulation module modulates radio frequency signals, so that the radio frequency signals carried by the X and Y polarization sub-modulators in the two modulators are differential signals.The polarization separation module separates the X and Y polarization states by a polarization beam splitter.The data processing module uses maximum ratio combining algorithm to suppress the power periodic fading caused by dispersion.The present scheme greatly reduces the sampling rate requirement of the backend ADC, and realizes high-fidelity real-time acquisition of ultra-wideband transient signals with low-cost hardware.

The application discloses a multi-component gas synchronous detection device and method based on differential filter modulation. The device comprises a multi-waveband light source module, a differential filter modulation module, a photoelectric detection module and an information processing module. The differential filter modulation module comprises a gas filter disc integrating multiple filter units. Each filter unit comprises a reference cell filled with high-concentration to-be-detected gas and a measurement cell filled with inert gas or a cavity. The photoelectric detection module comprises a long optical path absorption cell through which mixed gas to be detected is introduced in real time. The multi-waveband light source module emits multiple discrete waveband light signals in time division. The gas filter disc makes the light signals alternately pass through the corresponding reference cell and measurement cell through reciprocating swing, so that the light signals are obtained after differential modulation. The modulated light signals are attenuated after passing through the long optical path absorption cell and are then converted into electric signals. The information processing module demodulates the electric signals and calculates the concentration of the to-be-detected gas in the mixed gas through a differential absorption algorithm, so that the synchronous detection of the multi-component gas is realized.