182 results about "Frequency-division multiplexing" patented technology

The invention discloses an earthquake early warning device and method based on campus broadcast, and the method comprises the steps: carrying out the building response coupling analysis through receiving an early warning signal of an earthquake monitoring center, generating an earthquake magnitude-building coupling feature, and mapping the earthquake magnitude-building coupling feature into an enhanced early warning source adaptive to an acoustic environment; acoustic cavity detection is carried out based on threatened area identification, and differential playing topology is constructed; extracting a high-risk gathering area through personnel density scanning, generating personalized evacuation guiding content and determining a playing priority; high-precision time sequence control is realized by adopting a synchronous reference anchor point technology, and a multi-mode playing domain is constructed through carrier modulation and frequency division multiplexing; and finally, an acoustic navigation field is utilized to guide accurate scheduling and playing of audio signals, differential playing and accurate coverage of early warning information can be realized according to the anti-seismic characteristics and acoustic environment characteristics of different buildings, and an intelligent acoustic solution is provided for campus earthquake early warning.

The invention provides an MEMS (Micro Electro Mechanical System) micromirror array chip, a module and optical scanning equipment. The MEMS micromirror array chip comprises a plurality of micromirror structures, a substrate, a vertical lead structure and a capacitance angle sensing structure, according to the micro-mirror array chip integrated with the capacitive sensor, array-level real-time angle detection, feedback control and high-precision scanning angle detection are realized, and the micro-mirror array chip is fast in driving and resistant to interference; meanwhile, the wiring density is reduced by frequency division multiplexing isolation signals; in addition, the application of a monolithic integrated capacitance angle sensor in a high-density micro-mirror array chip is realized by a thick substrate with a silicon through hole; and finally, the micromirror array chip of the monolithic integrated capacitance angle sensor is used for precision optical scanning equipment, a photoelectric angle detector is omitted, optical scanning high-precision real-time angle detection and feedback control, high-precision angle detection and high-speed scanning are realized, the use design is convenient, and the cost is low.

The invention discloses a double-index modulation simulated radio frequency division multiplexing (AFDM) communication method. The method comprises the following steps: step 1, a transmitting end performs serial-parallel change; step 2, obtaining a transmission signal according to the index position of the joint selection AFDM activation subcarrier in the mapping table, the modulation bit mapping and the pre-chirp parameter of the activation subcarrier; step 3, obtaining a time domain signal; 4, performing parallel-serial conversion on the time domain signal; step 5, performing propagation transmission through a time-varying channel based on the time domain signal; step 6, constructing a time domain channel matrix, and performing serial-to-parallel conversion on the time domain receiving signal to obtain a receiving signal; step 7, performing channel estimation on the chirp parameter equivalent channel matrix; step 8, detecting an activated subcarrier position, an activated subcarrier modulation bit and an activated subcarrier pre-chirp parameter based on the chirp parameter equivalent channel matrix, and performing pre-chirp parameter transformation; and step 9, recovering the bit stream through parallel-serial change. The spectrum efficiency of the AFDM system is further improved, and the bit error rate is reduced.

The application belongs to the technical field of distributed optical fiber sensing, and particularly relates to a long-distance distributed optical fiber broadband acoustic vibration sensing system. The application utilizes the same laser to transmit and generate back Rayleigh scattering light and interference light in the same sensing optical fiber, and further constructs a distributed optical fiber acoustic vibration sensing system combined with Φ-OTDR and MZI, which comprehensively utilizes the performance advantages of both, utilizes a very simplified optical system scheme, realizes the function fusion of the two sensing structures on one sensing optical fiber, reduces the resource waste caused by the transmission of sensing signals by different sensing optical cables respectively, maximizes the optical fiber resource utilization rate, and reduces the system cost; utilizes a frequency division multiplexing demodulation scheme in the digital domain, expands the frequency response range on the basis of ensuring the high positioning accuracy of the system, realizes the simultaneous detection of the two systems by a single core, simultaneously realizes the high positioning accuracy and the continuous non-blind area detection in the broadband frequency range, and improves the reliability.

Aspects of the present disclosure are directed to techniques to ensure that other UEs that may have reserved resources within the same resource selection window are allowed (or at least not prevented) from gaining access to the shared channel during their respective reserved resource period for both Out-of-COT and in-COT preemption window period.

The invention relates to the technical field of low-orbit satellite communication, and discloses a multi-channel simultaneous calibration method, system and device based on FDM (frequency division multiplexing) and a medium, which realize high-precision synchronous estimation and compensation of multi-channel amplitude, phase and delay parameters through a frequency division multiplexing and parallel processing mechanism based on FDM. The problem of channel inconsistency in coaxial cable FDM transmission is effectively solved, the calibration efficiency and the system transmission performance are remarkably improved on the premise that the high precision that the amplitude error is not larger than 0.2 dB, the phase error is not larger than 2 degrees and the delay error is lower than 0.01 sampling point is ensured, meanwhile, the calculation complexity and the sequence overhead are reduced, and the system performance is improved. The method is suitable for calibration requirements of high-frequency-width multi-channel systems such as a large phased array of a low-orbit satellite and the like.

Various aspects of the present disclosure generally relate to communication. In some aspects, a first device may determine a frequency division multiplexing (FDM) configuration for a set of component carriers associated with a cable frequency spectrum, wherein each component carrier in the set of component carriers is associated with a number of multiple input multiple output (MIMO) layers. The first device may communicate with a second device over a cable infrastructure according to the FDM configuration for the set of component carriers. Numerous other aspects are described.

The invention relates to the technical field of medical surgical navigation, and discloses an intraoperative instrument position real-time visual tracking system which comprises a preoperative three-dimensional reconstruction unit, an intraoperative positioning unit, a coordinate matching unit, an error compensation unit and a visual display unit which are in bidirectional communication through a data bus. According to the intraoperative instrument position real-time visual tracking system and method, the problem of electromagnetic interference is solved through a magnetoelectric fusion positioning engine and a dynamic magnetic field calibration module, and the magnetoelectric fusion positioning engine receives a gradient magnetic field signal generated by an electromagnet array and an electric field signal of a body surface reference electrode; the dynamic magnetic field calibration module is combined with the frequency division multiplexing technology to separate double-frequency signals, then space-time registration is carried out through the magnetoelectric conversion matrix, alignment of a magnetic sensor and a magnetic beacon coordinate system is not needed, magnetic field distortion caused by a metal instrument can be counteracted, angle calculation errors can be reduced through bimodal signal complementation even if the posture of the instrument changes, and the precision of the instrument is improved. And positioning accuracy is improved.

The application provides a phase-sensitive optical time domain reflectometer, a measurement method and a readable storage medium, wherein a signal generation circuit of the phase-sensitive optical time domain reflectometer is configured to generate a radio frequency signal to drive an optical intensity modulator to modulate probe light, so that two groups of frequency division multiplexing sequences with differences can be used to synchronously detect a sensing optical fiber to be measured, a differential unfolding algorithm is combined to accurately solve a phase change amount in adjacent sampling intervals, and then demodulation results corresponding to different frequency parts are respectively unfolded to obtain unfolded phase results, so that the problem of large strain phase folding is solved and a large strain range is recovered, and further, the unfolded phase results are rearranged and combined in time sequence through time sequence interleaving processing of the unfolded phase results, so that a high sampling rate and a distortion-free reconstruction result are reconstructed, and therefore, the application can realize accurate measurement of high frequency response and large strain range dynamic strain.

The invention discloses a TFDM-PON system correction method and device, and the method comprises the steps: an OLT receives a dual-polarization signal transmitted by an ONU based on time division multiplexing or time-frequency division multiplexing, the dual-polarization signal comprises a target signal sequence corresponding to X / Y polarization, and the target signal sequence is an IQ period complex signal, and an I path and a Q path of the IQ period complex signal are single-tone signals of a first frequency and a second frequency respectively; target parameters including target transmitting and receiving end frequency deviation, IQ time delays of a target transmitting end and a target receiving end and target power deviation among ONUs are calculated based on Fourier transform and frequency domain symmetry of the dual-polarization signals, so that the ONUs carry out frequency, time delay and power correction according to the target parameters. Subcarrier crosstalk caused by frequency offset in TDM uplink burst transmission, mirror image crosstalk caused by IQ imbalance and performance degradation caused by power imbalance between subcarriers are eliminated, the bit error rate is reduced, and the system robustness is improved.

The application discloses an anti-interference pulse laser frequency division multiplexing optical coding wireless communication system and method, provides an optical wireless communication system based on pulse laser, and realizes an anti-interference pulse laser frequency division multiplexing optical coding communication method. Relying on the convergence effect of the light collector, a stable and anti-interference system receiving end is realized, the anti-interference capability of the whole system is realized through a pulse laser source and a multi-channel light splitting module, the utilization rate of the spectrum in the system communication process is improved, and the pulse laser transmission of frequency division multiplexing is realized.

The invention relates to a communication method, a terminal, network equipment, a system and a storage medium. The method comprises: sending a first configuration parameter to a terminal, the first configuration parameter being used for determining first frequency information of an uplink communication signal, and receiving the uplink communication signal sent by the terminal according to the first frequency information, the uplink communication signal being carried by a back reflection signal corresponding to a CW signal. Therefore, the first frequency information of the uplink communication signal sent by the terminal is determined according to the first configuration parameter, and the uplink communication signal is transmitted based on the first frequency information, so that frequency division multiplexing of the Internet of Things equipment for backscattering based on the CW signal in the communication transmission process is realized.

The embodiment of the application provides a kind of unmanned plane high-precision positioning and tracking method and device based on AFDM waveform, through echo signal and local linear frequency modulation reference signal analog domain dechirp mixing is low-pass filtered and baseband sampling to obtain baseband difference frequency data write signal processing buffer area, combined with affine frequency division multiplexing modulation parameter driven discrete affine Fourier transform time delay Doppler domain two-dimensional spectrum peak search and interpolation refinement to obtain target distance estimate and Doppler frequency shift estimate encapsulation as positioning and tracking parameter group, through flight control unit according to preset trajectory constraint condition executes position solution to obtain current positioning coordinate joint tracking filter state update to obtain target tracking trajectory data output to ground monitoring terminal, effectively solve the deficiency of traditional technology in analog domain difference frequency preprocessing, time delay Doppler domain high-precision parameter estimation and flight control linkage tracking filtering output etc., provide technical support for unmanned plane high-precision positioning and accurate tracking.

In the communication method, a first device generates a first signal, the first signal comprises M1 elements, M1 is determined based on M2 and a first parameter, M1 is a positive integer greater than M2, and M2 is a positive integer. The first device precodes the first signal to obtain a second signal, wherein the second signal comprises M1 elements. And the first device sending a third signal on a first frequency domain resource, the first frequency domain resource including M2 frequency domain units, the third signal being generated based on M2 elements selected from M1 elements included in the second signal. Visibly, according to the method, the time domain FTN is realized by transmitting the information amount of the M1 elements included in the first signal on the M2 frequency domain units. According to the method, the symbol duration is not changed, when the method is applied to a scene of multi-user frequency division multiplexing or MU-MIMO transmission, the symbol durations adopted by multiple users are the same, the CPs are aligned, and inter-user interference caused by different symbol durations of the multiple users is avoided.

The invention discloses a traditional Chinese medicine rubia cordifolia residue and polylactic acid composite material for FDM-3D (Frequency Division Multiplexing-Three Dimensional) printing, which is prepared by the following steps: firstly, drying rubia cordifolia residue at 60 DEG C and carrying out 5% NaOH alkali treatment on the rubia cordifolia residue so as to improve the surface roughness and interface affinity of fibers; then, the radix rubiae dregs are blended with PLA and a compatilizer according to the mass fraction of 10%, the temperatures of three temperature zones T, T2 and T3 of a machine barrel of a screw extrusion device are set to be 170 DEG C, 180 DEG C and 175 DEG C respectively, the rotating speed of a screw is set to be 18 rpm, and the composite wire is prepared through screw extrusion. The obtained composite material has the characteristics of antibiosis, slow release and rapid degradation, and can be widely applied to 3D printing models.

The present application provides a communication method and a related apparatus, effectively avoiding interference between users during multi-user frequency division multiplexing. The method comprises: mapping N elements to a second frequency domain resource to generate a first signal, the second frequency domain resource comprising N second frequency domain units, the N second frequency domain units being determined on the basis of M first frequency domain units and a first parameter, the first parameter being greater than 0 and not 1, M and N being positive integers, and N being greater than M; and sending the first signal on the basis of a first frequency domain resource, the first frequency domain resource comprising the M first frequency domain units.

A kind of well temperature field reconstruction and thermal disaster early warning method and system based on acoustic tomography, method: staggeredly arranging explosion-proof loudspeaker array and microphone array on the two sides of roadway in monitoring area;Utilize frequency division multiplexing technology to emit / receive multiple frequency band acoustic waves synchronously, form entity acoustic path data set, and construct overdetermined equation group;Adopt virtual sound line method, realize virtual path enhancement;Realize high-resolution temperature field reconstruction of roadway cross section temperature field in combination with sound velocity-temperature linear model;Continuous multiple frame temperature field images are input into TimesNet model, and multi-scale features are extracted by adaptive period decomposition and two-dimensional space-time convolution, and fire warning grade and abnormal area coordinates are output.The system: including explosion-proof loudspeaker array, microphone array, edge computing node and host computer;Edge computing node is connected with explosion-proof loudspeaker array and host computer respectively.The present application can realize global temperature perception and concealed fire early warning in target monitoring area.

Methods, systems, and devices for wireless communications are described. Described techniques provide for procedures, conditions, and signaling, based on which a user equipment (UE) may determine whether to transmit uplink control information (UCI) via a single repetition or multiple repetitions when two frequency division multiplexed (FDM) repetitions are scheduled for a UE. For example, the network may indicate that the UE is to adopt a first behavior (e.g., transmit UCI via a single repetition) or a second behavior (e.g., transmit UCI via both repetitions). If the UE is configured to transmit the UCI via both repetitions, then the UE may determine if one or more conditions are satisfied. If such conditions are not met, then the UE may default to the first behavior. The UE may determine which behavior to apply based on explicit signaling from the network, a type of UCI, or a combination thereof.

The application provides a bandwidth expansion method and device based on Rydberg atoms. The bandwidth expansion method comprises processing a received original signal to obtain a plurality of microwave signals corresponding to the original signal, wherein the plurality of microwave signals comprise a first microwave signal and a second microwave signal; performing mixing processing on the first microwave signal by a first atomic gas chamber to obtain a first bandwidth signal, and performing mixing processing on the second microwave signal by a second atomic gas chamber to obtain a second bandwidth signal; and synthesizing the first bandwidth signal and the second bandwidth signal by using a frequency division multiplexing method to realize bandwidth expansion. According to some embodiments, different Rydberg final states are prepared by using microwave signals of different frequencies, and the original signal is decomposed into a plurality of signals by using a frequency division multiplexing technology to realize multi-channel data transmission by loading the signals into the microwave signals, thereby realizing high-bandwidth multi-channel data transmission communication and bandwidth expansion.

The application relates to a channel estimation method of an affine frequency division multiplexing waveform based on compressed sensing. The method comprises the following steps: establishing an affine frequency division multiplexing waveform model based on compressed sensing; according to the affine frequency division multiplexing waveform model based on compressed sensing, an initial channel vector is calculated by using a compressed sensing algorithm; the initial channel vector is taken as a first channel vector; pilot interference cancellation is performed on the first channel vector to obtain a second channel vector; data detection is performed on the second channel vector to obtain a first detection data vector; according to the first detection data vector and the affine frequency division multiplexing waveform model based on compressed sensing, a third channel vector is calculated by using the compressed sensing algorithm; the third channel vector is taken as a new first channel vector, and the operation is repeated until a preset condition is reached; and the third channel vector is taken as final channel estimation. The method has the characteristics of strong stability and high efficiency.

A frequency division multiplexing functional chip comprises a first straight waveguide, a second straight waveguide, a third straight waveguide, a first echo wall mode micro-ring waveguide, a second echo wall mode micro-ring waveguide, a third echo wall mode micro-ring waveguide, a fourth echo wall mode micro-ring waveguide, a fourth echo wall mode micro-ring waveguide, a third echo wall mode micro-ring waveguide and a fourth echo wall mode micro-ring waveguide. Wherein the first straight waveguide, the first echo wall mode micro-ring waveguide, the second echo wall mode micro-ring waveguide and the second straight waveguide form a group of uploading-downloading echo wall mode micro-ring resonant cavities; the first straight waveguide, the third whispering gallery mode micro-ring waveguide, the fourth whispering gallery mode micro-ring waveguide and the third straight waveguide form another group of uploading-downloading whispering gallery mode micro-ring resonant cavities, and the two groups of uploading-downloading whispering gallery mode micro-ring resonant cavities are different in resonant frequency; resonance is generated and filtering screening is carried out on the specific-frequency terahertz signals transmitted by the first straight waveguide, so that a frequency division multiplexing function is realized. According to the invention, the dense narrowband frequency division multiplexing function is realized, and the narrowband frequency division multiplexing of the terahertz device is enriched.

The invention provides a method executed by user equipment (UE) and the UE. The method comprises the following steps: UE in an idle state or an inactive state receives configuration parameters of low-power-consumption wake-up signal (LP-WUS) resources from a base station; and the UE configures a frequency division multiplexing coefficient in the parameters according to the LP-WUS resource; a time domain repetition coefficient; and transmitting at least one of the configuration indication TCI parameters, determining a plurality of LP-WUS detection opportunities (LP-WUS MO) for detecting the LP-WUS, and a reference signal related to the LP-WUS MO. Therefore, the UE can correctly determine a plurality of opportunities for detecting the wake-up signal, the connection between the UE and the network is maintained, and the power consumption of the UE is reduced.

The application discloses a wireless optical transmission method based on asymmetric clipping optical affine frequency division multiplexing, and relates to the technical field of wireless communication. The method comprises the following steps: S1, pre-processing input signal data, including mapping, design of modulation symbols and symmetry construction, to generate a frequency domain signal; S2, mapping the frequency domain signal to a time domain based on a real number discrete affine Fourier transform to generate an affine frequency division multiplexing (AFDM) signal; S3, asymmetrically clipping the AFDM signal, transmitting the AFDM signal to a receiving end through an optical communication channel, and inversely restoring the AFDM signal, including recovering the clipped signal and demodulating data; and S4, designing a real number DAFT kernel function, deducing a new c1 parameter range, realizing complete separation of signal paths with different delays in the DAFT domain, and achieving full diversity. The application solves the signal distortion problem caused by the multipath effect in optical communication.

The invention belongs to the technical field of power distribution network communication processing, and particularly relates to a multi-device converged communication processing method for power distribution network automation. Equipment sub-signals adopt single modulation and are distributed with different frequency bands, and a multi-channel transmission scheme is established by adopting a frequency division multiplexing carrier modulation method based on a power distribution network communication system; signal modulation processing based on a power distribution network transmission environment; and respectively performing transmission optimization on the data by using the sending end and the receiving end. On the basis of the existing transmission network, the information transmission efficiency and capability, especially the capability of multi-device joint communication processing, are further enhanced.

The present application provides a data transmission method and device. The method comprises: when a DMRS sequence in a DMRS symbol is frequency division multiplexed with first data in the DMRS symbol, a first device multiplying the first data by a coefficient β, wherein coefficient [equation]; outputting the DMRS symbol and a data symbol to a second device, wherein the data symbol comprises second data, and the DMRS symbol and the data symbol are located on different time domain resources; and indicating a first EPRE ratio and / or a second EPRE ratio to the second device, wherein the first EPRE ratio is related to β, the second EPRE ratio is related to β, the first EPRE ratio represents the ratio of EPRE of the first data to EPRE of the DMRS sequence, and the second EPRE ratio represents the ratio of EPRE of the second data to EPRE of the DMRS sequence. By means of the implementation, the data transmission efficiency during frequency division multiplexing of the DMRS sequence and a single carrier sequence can be improved.

Provided in the present application is a communication method, which is executed by a sending end. The method comprises: on the basis of a first modulation solution, modulating a first bit stream to obtain a first data signal; on the basis of a second modulation solution, modulating a second bit stream to obtain a second data signal; and sending a reference signal and the second data signal, the reference signal comprising the first data signal and a DMRS sequence, the first data signal and the DMRS sequence being located in different frequency domain resources, the reference signal and the second data signal being located in different time domain resources, and the order of the first modulation solution being lower than the order of the second modulation solution. In a frequency division multiplexing mode of the DMRS sequence and data, the technical solution can ensure that the PAPR of the reference signal is not lower than the PAPR of the second data signal.

The application discloses a semantic communication method and system based on interleaved frequency division multiplexing, belongs to the field of semantic communication, and is applied to a semantic communication system. The method comprises the following steps: a sending end extracts semantic information through a semantic encoder and transmits the semantic information after modulation through interleaved frequency division multiplexing; a receiving end reconstructs a semantic signal based on a received signal through a cross-domain iterative detector and completes a target task through a semantic decoder. The cross-domain iterative detector performs linear detection in a time domain by utilizing channel sparsity, performs nonlinear detection in a characteristic domain based on a fractional model, and realizes cross-domain transformation through an interleaved frequency division multiplexing modulation matrix with universal characteristics. The application can realize training of an encoder / decoder and decoupling of a channel through interleaved frequency division multiplexing modulation, the channel has strong universality, and the compatibility with an existing digital communication system is good. Since the type of the encoder / decoder is not limited, the whole system can perform multiple tasks, and the task universality is good.

This invention belongs to the field of satellite telemetry, tracking, and command (TT&C) technology, and provides a method and system for real-time scheduling of short message resources during overseas orbit control. The method includes: satellite control software constructing a short message frame library and pre-configuring fixed-length normal frames and orbit control-specific frames; attitude and orbit control software monitoring orbit control status in real time, satellite control software identifying orbit control ignition commands and orbit control stage markers, and initiating a dual-queue parallel transmission mechanism; configuring the link for relay satellites according to the dual-queue parallel transmission mechanism and implementing frequency division multiplexing downlink; and entering a transition period after orbit control monitoring ends, performing periodic attenuation control on the orbit control-specific frames. This invention solves the problem of real-time status monitoring failure for geostationary orbit satellites during overseas orbit control, increasing the orbit control anomaly identification rate to over 99%, breaking through monitoring real-time limitations, and significantly improving the safety and controllability of overseas orbit control; optimizing resource utilization, enhancing adaptive capabilities, and achieving second-level on-demand downlink of key parameters and dynamic optimization of channel resources.

The invention discloses a high-spectral-efficiency and high-speed FTN (Fourier Transform Network) transmission method based on pseudo code auxiliary carrier synchronization, which belongs to the field of high-frequency wireless communication, and comprises the following steps: a transmitting end composites a low-speed pseudo code pilot signal into a high-speed FTN signal by adopting a frequency division multiplexing mode to obtain a composite signal and outputs the composite signal; a receiving end performs down-conversion on the received composite signal, and the composite signal is separated by a filter to obtain a low-speed pseudo code pilot frequency sequence and a high-speed FTN sequence; carrying out carrier frequency offset estimation based on the low-speed pseudo code pilot frequency sequence to obtain a frequency offset estimation value; performing frequency offset compensation on a receiving end carrier by adopting the frequency offset estimation value to obtain a compensated high-speed FTN sequence; and carrying out symbol estimation on the compensated high-speed FTN sequence by adopting a forward backtracking continuous symbol sequence detection algorithm to obtain a received signal. According to the invention, the receiving sensitivity and the system robustness can be ensured while high-spectrum-efficiency transmission is realized.

The invention discloses a method for realizing optical cable fiber core health prediction by using a B-OTDR technology, which comprises the following steps: a multi-physical quantity fusion detection module synchronously obtains Brillouin scattering and Raman scattering signals by using a double-pulse modulation technology, separates two kinds of scattered light through frequency division multiplexing, and constructs a strain-temperature decoupling model; and the dynamic self-adaptive sampling module automatically switches sampling resolution according to the position of the optical fiber, adopts high-resolution continuous scanning on a historical fault high-incidence area, adopts low-resolution sparse sampling on a normal area, and automatically triggers local encryption sampling when an abnormal event is detected. The double pulses are respectively calculated by adopting a double-pulse modulation technology, so that the prediction accuracy is improved; dynamic self-adaptive sampling is adopted, segmented sampling is carried out on a high fault area and a normal area, meanwhile, local sampling is carried out on an abnormal section, the invalid data volume is reduced, and meanwhile the monitoring precision of a key area is ensured.