147 results about "Modulation pattern" patented technology

The invention discloses a low-cost three-dimensional live-action measurement and holographic reconstruction method and system for fringe projection, and the method comprises the steps: sequentially capturing at least three first object modulation images and five second object modulation images, which are obtained after sine and Gray code fringe patterns are modulated by the surface depth of an object to be measured, through a projector and a first camera; reconstructing three-dimensional shape information by using a multi-step phase shift method and a complementary Gray code phase unwrapping method to obtain a depth map of the surface of the object to be measured; according to the holographic reconstruction method, the obtained depth map is used, a projector and a first camera are used for obtaining an intensity map of the surface of an object to be measured when no projection fringe pattern exists, the intensity map is divided into a plurality of slice images in the depth direction of the depth map, sub-holograms are obtained according to an iterative Fresnel algorithm and a fast Fourier transform algorithm, and the sub-holograms are reconstructed. And after superposition and phase extraction, a phase hologram is obtained. According to the invention, the depth map can be simply, conveniently, efficiently and losslessly obtained with low cost and high precision, and popularization and application of the digital holographic technology are facilitated.

The invention relates to the technical field of data processing, and discloses a signal intra-pulse modulation pattern recognition method and system, and the method comprises the steps: receiving a radar pulse signal; performing short-time Fourier transform on the radar pulse signal; in the time-frequency matrix, calculating an energy distribution gradient of each time point along a frequency axis; according to the energy distribution gradient of each time point, identifying gradient abrupt change points; determining a filtering bandwidth boundary based on the gradient catastrophe point by adopting a negative feedback regulation mechanism of bandwidth and signal-to-noise ratio; based on the filtering bandwidth boundary, performing bandwidth filtering on the radar pulse signal; calculating an instantaneous frequency, a first-order differential frequency and a second-order differential frequency of the filtered signal through Hilbert transform, and forming a feature vector; predicting a cluster number range through a long and short term memory neural network according to the feature vectors; according to the feature vector, through a K-Means clustering algorithm, carrying out clustering analysis in a clustering number range; and outputting a modulation style label according to a clustering analysis result.

The invention relates to a dual-mode communication carrier signal modulation method and device based on an OFDM (Orthogonal Frequency Division Multiplexing) system, and the method comprises the steps: obtaining the signal-to-noise ratio of a plurality of subcarriers transmitted by a receiving end, and recognizing at least one target subcarrier of which the signal-to-noise ratio of the plurality of subcarriers is in a configured frequency band range, determining a target modulation mode according to the average value of the signal-to-noise ratio of the at least one target subcarrier; determining the bit mutual information of each target subcarrier according to the target modulation mode and the signal-to-noise ratio of the at least one target subcarrier, and correcting the bit mutual information of each target subcarrier based on the configured diversity times to obtain the corrected bit mutual information of each target subcarrier; calculating a bit mutual information average value according to the corrected bit mutual information of each target subcarrier, and determining a code rate of the to-be-modulated data based on the bit mutual information average value; and modulating the to-be-modulated data according to the code rate of the to-be-modulated data, the target modulation mode, the configured diversity times, the configured frequency band range and the target subcarrier.

The invention relates to the technical field of energy storage converters, in particular to a three-level inverter DPWM and SVPWM smooth switching method and system, a medium and equipment, and the method comprises the steps: determining a current modulation mode which comprises the SVPWM and the DPWM; a first modulation coefficient and a second modulation coefficient are set, the first modulation coefficient corresponds to the weight of the SVPWM common-mode voltage, the second modulation coefficient corresponds to the weight of the DPWM common-mode voltage, and the sum of the first modulation coefficient and the second modulation coefficient is constantly 1; determining values of a first modulation coefficient and a second modulation coefficient based on the current modulation mode in response to a switching instruction of switching from the current modulation mode to a target modulation mode; and combining the three-phase SPWM modulation wave, the first modulation coefficient, the SVPWM common-mode voltage, the second modulation coefficient and the DPWM common-mode voltage to generate a total modulation wave. According to the invention, non-stop switching of SVPWM and DPWM is realized, fast and stable neutral-point voltage and smooth transition of neutral-line current and three-phase current are ensured when two modulation modes are switched, and the smooth transition requirement of mode switching is met.

A deep learning-enabled system for the display or projection of high-resolution images is disclosed that is based on a jointly-trained pair of an electronic encoder network and an all-optical decoder network to synthesize / project super-resolved images using low-resolution wavefront modulators. The electronic encoder network rapidly pre-processes the high-resolution images of interest so that their spatial information is encoded into low-resolution (LR) modulation patterns, projected via a low SBP wavefront modulator. The all-optical decoder network processes this LR encoded information using thin transmissive layers that are structured using deep learning to all-optically synthesize and project super-resolved images at its output FOV. Results indicate that this diffractive image display system can achieve a super-resolution factor of ˜4, demonstrating a ˜16-fold increase in SBP. The system can be scaled to operate at visible wavelengths and be used for large FOV and high-resolution displays that are compact, low-power, and computationally efficient.

The invention relates to the technical field of radars, in particular to a low-interception-probability radar waveform design method and device, and the method comprises the steps: obtaining a preset MDP tuple; constructing a Markov decision model framework based on a preset MDP tuple, wherein the Markov decision model framework comprises a design framework corresponding to the power adopted for constructing a radar waveform and the complexity of a radar waveform intra-pulse modulation pattern; performing reinforcement learning on the Markov decision model framework in a strategy optimization direction taking maximization of long-term accumulated rewards as a target to obtain a reinforcement learning optimization model of radar waveform design; and solving the reinforcement learning optimization model of the radar waveform design by using a model-free Q-learning algorithm to obtain the design parameters of the radar wave, thereby realizing the intelligent design of the low-interception probability radar waveform in the complex electronic countermeasure environment, and improving the concealment and detection performance balance capability of the radar in the unknown countermeasure environment.

This invention provides a communication countermeasure simulation method based on random simulation, belonging to the field of electronic countermeasure simulation technology. The method first establishes a probability distribution model of reconnaissance information deviation for key parameters of the communication target; then, based on the probability distribution model of each parameter deviation, independent random sampling is performed to generate instantaneous values ​​of frequency deviation, positioning deviation, and modulation pattern recognition results at each moment, and the guidance parameters of the jammer are determined; next, the instantaneous interference-to-signal ratio (ISR) at the target receiver at the current moment is calculated; finally, the ISR calculated at the communication receiver is compared with a preset communication performance degradation ISR threshold to determine whether the jamming is successful. The model of this invention has clear physical meaning and can accurately quantify the impact of reconnaissance information deviation and propagation loss on the jamming effect, significantly improving the credibility and practicality of the simulation evaluation.

Example embodiments of the present disclosure are directed to dynamic selection of index modulation pattern subset. A method comprises receiving, from a second apparatus, configuration information indicating at least one pattern subset for index modulation; determining a target pattern subset for index modulation from the at least one pattern subset; and applying at least one portion of the target pattern subset to a communication between the first apparatus and the second apparatus.

This application discloses a method and related apparatus for identifying underwater acoustic signal modulation patterns, relating to the field of signal modulation pattern identification in non-cooperative underwater acoustic communication. The method first acquires the original passband signal and processes it to obtain two complex signals, I and Q. Using a residual convolutional network module, the spatial features of the I and Q complex signals are extracted to obtain a spatial feature sequence. Then, using a bidirectional gated recurrent unit module, information from the spatial feature sequence is learned from both forward and backward directions, and the learned information is concatenated to obtain a temporal feature vector. The temporal feature vector is then subjected to feature mapping and classification to obtain classification confidence scores for different modulation patterns. The modulation pattern corresponding to the highest classification confidence score is determined as the classification result. This application enables high-precision, automated identification of underwater acoustic signal modulation patterns.

The invention discloses an inverter control method and energy storage equipment. The inverter control method comprises the following steps: acquiring the output power of an inverter; determining a modulation mode of the PWM signal according to the output power; the modulation mode of the PWM signal comprises a discontinuous pulse width modulation mode and a space vector pulse width modulation mode; determining a switching frequency parameter of the inverter according to the modulation mode of the PWM signal; the switching frequency parameter comprises at least one of a switching frequency jitter depth, a switching frequency jitter mode and a switching frequency updating speed; a PWM signal is generated based on the switching frequency parameter. The EMC performance of the inverter is comprehensively improved, and the robustness is higher. And meanwhile, the efficiency of the inverter is improved, the dependence on a large-size and high-cost EMI filter is reduced or simplified, the implementation and upgrading are easy, and integration in a product and optimization on site through fixed upgrading are facilitated. And the compactness of the overall structure of the inverter is improved, and the power density of a power system is improved.

A single-pixel imaging method for an object retracing a motion trajectory, a system, a medium, and a device. The method comprises: a controller generating, according to a predefined formed-image reconstruction algorithm, a modulation pattern sequence having different spatial distributions, and inputting the modulation pattern sequence into a light modulation apparatus (S1); the light modulation apparatus receiving a trajectory pulse signal from a digital signal processor, and simultaneously sending a modulated pulse signal to a synchronous multi-channel signal acquisition apparatus (S2); the synchronous multi-channel signal acquisition apparatus receiving the modulated pulse signal, and being triggered to acquire, at a predetermined sampling frequency, a plurality of sample values of a sampled light signal illuminating an object to be imaged and detected by a first detector (S3); the controller selecting a target sample value from among the sample values as a formed-image reconstruction sample value, the formed-image reconstruction sample value corresponding to a target modulation pattern in the modulation pattern sequence (S4); repeating the above steps until each formed-image reconstruction sample value corresponds to each modulation pattern in the modulation pattern sequence on a one-to-one basis, and generating a formed-image reconstruction sample value sequence on the basis of each formed-image reconstruction sample value (S5); on the basis of the formed-image reconstruction algorithm, the controller performing image reconstruction on the formed-image reconstruction sample value sequence to generate a single formed image of the object to be imaged (S6); and repeating the above steps until a count of generated single formed images reaches a predetermined number (S7). The imaging system is capable of imaging, over an extended period of time, high-speed objects retracing a motion trajectory at varying velocity.

This invention relates to ranging and triangulation in a multi-sensor scanner. An optical scanner uses a ranging phase to determine a range to a subject, in which a series of image frames is received that collectively contain a ranging spot captured as a reflection off a surface of the subject. The captured ranging spot is time-modulated according to a modulation pattern, and the series of image frames is processed based on the modulation pattern to identify the ranging spot, determining possible locations of the ranging spot within at least one image frame of the sequence. This is followed by a triangulation phase in which the possible locations of the ranging spot are processed to produce a range determination. In an optional implementation, whether the possible locations of the ranging spot are within a reasonable location is assessed based on different device-specific positional offsets in the image frames captured by different ones of a plurality of image capture devices.

The invention relates to the technical field of oil-gas exploration logging, provides a logging work data real-time transmission system and method based on an embedded structure, and aims to solve the problems that in the prior art, data transmission is insufficient in real-time performance, a logging system is difficult to troubleshoot, and the data transmission efficiency is low. And the technical problem that the ground decoding board only supports cable communication of a single modulation mode is solved. Comprising a downhole instrument used for collecting original logging electric signals; the mode transformer is used for performing impedance matching processing on the original logging electric signal to obtain a preprocessed logging signal; the amplifier module is used for performing method processing on the preprocessed logging signal to obtain an amplified logging signal; the A / D conversion module is used for converting the amplified logging signal into a digital signal from an analog signal to obtain a digital logging signal; the modulation-demodulation module is used for decoding the digital logging signal to obtain a decoded logging signal; and the network communication module is used for uploading the decoded logging signal to logging acquisition software of an upper computer in real time.

The invention provides a modulation pattern identification method and device for an orthogonal frequency division multiplexing signal based on adaptive modulation, which can be applied to the technical field of wireless communication. The method comprises the following steps: acquiring an orthogonal frequency division multiplexing signal, wherein the orthogonal frequency division multiplexing signal comprises N symbols and K subcarriers; performing fast Fourier transform on the orthogonal frequency division multiplexing signal to obtain a frequency domain matrix of an NxK dimension; extracting a plurality of frequency domain symbol vectors associated with each subcarrier from the frequency domain matrix according to the identifiers of the K subcarriers based on the subcarrier dimensions to obtain K target data sequences; according to any target data sequence in the K target data sequences, performing at least one operation of clustering or accumulation on the target data sequences to obtain a plurality of modulation pattern recognition features associated with the target data sequences; and determining a target modulation pattern according to the plurality of modulation pattern recognition features and a preset modulation pattern mapping relationship.

The application discloses the technical field of level modulation, and relates to a switching loss equalization control system and method based on level hybrid modulation, and a storage medium, which comprises the following modules: a signal processing module, which is used to acquire a three-level modulation voltage; a mode switching decision module, which is used to acquire the difference between the internal and external tube losses, and update a modulation mode flag bit by comparing a hysteresis threshold value; and a level hybrid modulation module, which is used to read the three-level modulation voltage and the modulation mode flag bit, and execute three-level modulation or equivalent two-level modulation to output a final modulation wave for controlling the state of a switching tube. The mode switching decision module of the application takes the three-level modulation voltage as the final modulation wave when three-level modulation is performed, and allocates the duty cycle of the intermediate level of the three-level modulation voltage to the high and low levels to obtain a two-level modulation voltage and acquire the final modulation wave when equivalent two-level modulation is performed, so that the dynamic equalization distribution of the internal and external tube losses is realized, and the thermal stability and reliability of the system are improved.

The application discloses a kind of T type three-level converter open-circuit fault diagnosis method with strong robustness, belong to the field of power electronic equipment fault diagnosis, to distinguish different switch similar open-circuit fault characteristics and accurately locate open-circuit fault tube.Considering different modulation strategies and modulation modes, the phase voltage residual is generated through the phase voltage model, so as to extract the fault characteristics of the converter under various open-circuit faults.Analyze the influence of factors such as parameter error, dead time and delay time of the system on the phase voltage vector residual, and the adaptive residual vector amplitude threshold based on uncertainty propagation theory.A hierarchical fault diagnosis scheme is proposed, which can locate the group-level open-circuit fault according to the voltage residual vector amplitude and angle, switch the three-level modulation mode of all phases of the converter to two-level mode, to further identify the specific fault switch from the fault group.A reasonable balance between robustness and speed can be achieved, and the complexity and adaptability of the diagnosis algorithm are fully considered.

The invention provides a signal modulation identification method and system in an interference environment based on a neural network, and the method comprises the steps: obtaining a to-be-identified interference environment signal, inputting the to-be-identified interference environment signal into an interference adaptation module, and carrying out the correlation modeling of an interference feature and a signal feature, thereby obtaining an interference adaptation feature; inputting the interference adaptive features into an interference suppression layer of a signal modulation identification neural network, and carrying out interference component separation to obtain signal purification features; inputting the signal purification features into a modulation classification layer for modulation mode matching to obtain a preliminary modulation type identification result; then, the preliminary modulation type recognition result and interference type information in the interference adaptation features are subjected to correlation verification, and a final modulation type recognition result is obtained; and finally, generating a signal identification report containing modulation parameter description based on a final result, and sending the signal identification report to a target signal analysis terminal. The method can effectively cope with a complex interference environment, improves the accuracy and reliability of signal modulation identification, and provides powerful support for optimization of a communication system.

The application relates to a power line carrier target data modulation method and device, a storage medium and a chip. The method corrects the signal-to-noise ratio of each resource group based on a preset diversity number, then determines the bit number of each to-be-transmitted symbol sent based on the corrected signal-to-noise ratio, then calculates the to-be-transmitted symbol number according to the bit number of target data and the preset diversity number, and finally modulates the target data based on the modulation mode corresponding to the minimum to-be-transmitted symbol number and the preset diversity number by comparing the to-be-transmitted symbol numbers under different preset diversity numbers. The application dynamically adjusts the resource group configuration parameters according to the signal-to-noise ratio of each resource group, thereby adapting to the change of a channel condition, improving a communication rate and a communication success rate.

This disclosure provides a method and apparatus for modulation pattern recognition of orthogonal frequency division multiplexing (OFDM) signals based on adaptive modulation, which can be applied to the field of wireless communication technology. The method includes: acquiring an OFDM signal, which comprises N symbols and K subcarriers; performing a fast Fourier transform on the OFDM signal to obtain an NxK-dimensional frequency domain matrix; based on the subcarrier dimension and according to the identifiers of the K subcarriers, extracting multiple frequency domain symbol vectors associated with each subcarrier from the frequency domain matrix to obtain K target data sequences; performing at least one operation, such as clustering or accumulation, on any of the K target data sequences to obtain multiple modulation pattern recognition features associated with the target data sequences; and determining the target modulation pattern based on the multiple modulation pattern recognition features and a preset modulation pattern mapping relationship.

The application discloses a kind of adaptive QAM and OFDM bimodulus intracorporeal ultrasonic communication system and method based on channel estimation, belong to intracorporeal ultrasonic communication technical field, the transmitting end is configured with single carrier QAM modulation mode and multicarrier OFDM modulation mode, real-time evaluation intracorporeal ultrasonic channel quality in receiving end, according to the optimal modulation mode of evaluation result, according to the optimal modulation mode generation mode switching instruction, the mode switching instruction is sent to transmitting end, transmitting end according to the mode switching instruction seamlessly switches between single carrier QAM modulation mode and multicarrier OFDM modulation mode, so that transmitting end works in optimal modulation mode, the system and method can dynamically select optimal modulation mode according to intracorporeal channel real-time quality parameter, while ensuring that mode switching is reliably synchronized.

The invention provides an adaptive modulation switching method for satellite-ground laser communication. The performance of a communication system is improved by using 16QAM (Quadrature Amplitude Modulation) and BPSK (Binary Phase Shift Keying) modulation adaptive switching; the method comprises the following steps: firstly, carrying out polarization code coding on an information sequence, scattering the sequence through an interleaver, and then modulating the sequence through a modulator and sending the modulated sequence to a satellite-ground laser communication channel. An atmospheric turbulence estimation module is introduced at a receiving end, estimated atmospheric channel state information is fed back to a sending end through an estimated value of satellite-ground laser communication atmospheric turbulence intensity, then a modulation mode of the sending end is switched according to a threshold value, and low-time-delay reliable transmission of satellite-ground communication laser communication is achieved.

A laser processing apparatus includes: a placement unit on which a sample is placed; a laser light output unit for outputting laser light; a laser irradiation unit for irradiating the laser light output from the laser light output unit to the sample disposed in the placement unit; and a transmission member that is disposed on the optical axis of the laser beam between the sample disposed in the arrangement unit and the laser beam irradiation unit, and that transmits the laser beam, the laser beam irradiation unit including: a spatial light modulator that displays a modulation pattern; a first laser beam and a second laser beam are generated from the laser beam by modulating the laser beam according to the modulation pattern and are emitted; a condensing unit for forming a first condensing point by condensing the first laser beam and forming a second condensing point by condensing the second laser beam; and a control unit for controlling the spatial light modulator.

A data carrier (1) for a secure article (1000) comprises a carrier body (2) and at least one security element (3). The security element (3) comprises at least one primary security element (4) and at least one secondary security element (5) being encoded in the primary security element (4). The secondary security element (5) is configured to be decoded via at least one decoding device (6) and is configured such that, when being decoded with the decoding device (6), an appearance of the secondary security element (5) changes depending on a viewing angle under which the data carrier (1) is viewed. The primary security element (4) is modulated according to at least one modulation pattern, and wherein at a location of the secondary security element (5) the modulation pattern comprises at least one modification, whereby the secondary security element (5) is encoded in the primary security element (4). The modulation pattern is associated with a modulation pitch (MP) and a modulation orientation (MO). The modulation pitch (MP) mismatches a decoding pitch (DP) associated with the decoding device (6) and / or the modulation orientation (MO) mismatches a decoding orientation (DO) of the decoding device (6).

The invention relates to an X-ray imaging apparatus (1) comprising: an X-ray source (2) generating an X-ray beam (F); a two-dimensional X-ray detector (3) comprising pixels (3a); a sample holder (4) configured to support a sample (E); at least one modulator (5), the at least one modulator (5) being a film on which a helical transmission modulation pattern is formed.

The present application relates to a Bluetooth communication method and a device. The method may be performed by a first device. The first device may establish Bluetooth connection with a second device. The method may include: performing link communication with the second device according to a first modulation mode; in a case where it is detected that the quality of link communication is less than a preset threshold, adjusting the modulation mode of the first device from the first modulation mode to a second modulation mode, and performing the link communication with the second device according to the second modulation mode. The anti-interference capability of the second modulation mode is greater than that of the first modulation mode.

Example embodiments of the present disclosure are directed to dynamic selection of index modulation pattern subset. A method comprises receiving, from a second apparatus, first configuration information indicating at least one pattern subset for index modulation; determining, from the at least one pattern subset, a target pattern subset for index modulation for a transmission from the second apparatus to the first apparatus; and receiving the transmission from the second apparatus based on at least one portion of the target pattern subset.

This disclosure provides methods, components, devices and systems for signaling support for multiple coding schemes to a single user device spanning a frequency domain. A first wireless device may identify respective quality information associated a set of resource units (RUs) that span a frequency bandwidth. The first wireless device may transmit information signaling that indicates a first modulation and coding scheme (MCS) or a first modulation pattern to be applied to a first RU and a second MCS or a second modulation pattern to be applied to a second RU. The first wireless device may communicate first bits of a first service data unit via the first RU using the first MCS or the first modulation pattern, and second bits, of the first service data unit or of a second service data unit, via the second RU using the second MCS or the second modulation pattern.

A wireless local area network, WLAN, station (110) is disclosed for single user, SU, or multi user, MU, communication with one or more further WLAN stations (120) via one or more spatial streams using an equal modulation, EQM, mode or an unequal modulation, UEQM, mode based on a plurality of modulation and coding schemes, MCSs, including 16 legacy MCSs and a plurality of additional MCSs. The WLAN station (110) is configured to send an EHT or UHR Physical Layer Protocol Data Unit, PPDU, including a preamble to the one or more further WLAN stations (120), wherein the preamble comprises one or more user fields, wherein each user field has a format in accordance with the IEEE 802.11be, IEEE 802.11bn or IEEE 802.11ax standard and wherein each user field is configured to encode the plurality of MCSs, i.e. the 16 legacy MCSs and the plurality of additional MCSs.

The present invention relates to apparatus for non-invasive blood glucose monitoring, which includes: a signal transmitting module that transmits a terahertz wireless signal modulated into a PRBS pattern at a terahertz carrier frequency to a body part; a signal receiving module that demodulates the terahertz wireless signal reflected from the body part to measure performance parameters of the modulation pattern; and a sensing module that performs multivariate analysis using the performance parameters of the modulation pattern measured through the signal receiving module and quantifies features related to blood glucose through the multivariate analysis to measure blood glucose concentration.

A method for wireless communication is provided, relating to field of wireless communication and including: determining, by an access point device, a first beacon frame and a first modulation mode; and transmitting, by the access point device, the first beacon frame to a station device according to the first modulation mode; where the first beacon frame is a target beacon frame, and the first modulation mode is an original modulation mode; or, the first beacon frame is an original beacon frame, and the first modulation mode is a target modulation mode; or, the first beacon frame is the target beacon frame, and the first modulation mode is the target modulation mode; a length of the target beacon frame is shorter than a length of the original beacon frame, and a transmission rate corresponding to the target modulation mode is greater than a transmission rate corresponding to the original modulation mode.