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525 results about "Chirp" patented technology

A chirp is a signal in which the frequency increases (up-chirp) or decreases (down-chirp) with time. In some sources, the term chirp is used interchangeably with sweep signal. It is commonly used in sonar, radar, and laser, but has other applications, such as in spread-spectrum communications.

Tower grounding grid multi-frequency complex wave electric field imaging and soil environment medium diagnosis method

The invention discloses a tower grounding grid multi-frequency composite wave electric field imaging and soil environment medium diagnosis method, which comprises the following steps of: generating a composite excitation signal through superposition of a low-frequency sine wave and a high-frequency CHIRP square wave, and collecting multi-dimensional data such as voltage / current response, soil temperature and humidity, electric field intensity and the like in combination with a distributed sensor array; separating signal features by using wavelet transform and extracting impedance information of a target frequency point; a multi-grid homotopy algorithm is adopted to realize grounding grid three-dimensional resistivity distribution reconstruction, corrosion spots and abnormal areas are marked, and high-precision positioning of underground conductors is completed through UWB radar or a capacitance detector; meanwhile, based on the information entropy maximization optimization frequency band combination, the grounding grid state is comprehensively evaluated in combination with a multi-parameter fusion model. The method has the non-contact patrol capability, the unmanned aerial vehicle carries equipment to scan the grounding grid, the detection efficiency and convenience are remarkably improved, and an efficient and accurate solution is provided for guaranteeing safe operation of the power grid.
Owner:CHUXIONG POWER SUPPLY BUREAU OF YUNNAN POWER GRID CO LTD

Distributed feedback laser with double-layer grating structure

The invention provides a distributed feedback laser with a double-layer grating structure, and relates to the technical field of lasers, the laser forms an InGaAlAs multi-quantum well active region, an upper sampling grating layer and a lower phase shift grating layer on an n-type InP substrate in sequence, the upper grating layer is designed based on a reconstruction equivalent chirp technology, and the lower phase shift grating layer is designed based on a reconstruction equivalent chirp technology. Two sections of asymmetric modulation areas with sampling periods linearly gradually changing in opposite directions are arranged in the axial direction of the resonant cavity, and the lower grating layer is a quarter-wave phase shift grating matched with the period of the upper seed grating. Through the synergistic effect of equivalent phase modulation and phase shift generated by the double-layer grating, the photon density distribution in the cavity can be improved, the longitudinal space hole burning effect can be weakened, the sensitivity to end face phase fluctuation can be reduced, high single-mode power and large modulation bandwidth can be realized in a wide temperature range, and the double-layer grating is suitable for a high-speed optical communication and coarse wavelength division multiplexing transmission system.
Owner:XINCHEN SEMICON (SUZHOU) CO LTD

Metal microcrack ultrasonic detection method

The invention belongs to the technical field of metal crack detection, and discloses a metal microcrack ultrasonic detection method, which comprises the following modules: an ultrahigh frequency composite array probe with a center frequency dynamic adjustable range of 5-50 MHz; the dual-mode excitation and receiving module is used for independently generating a pulse reflection mode excitation signal and a diffraction mode chirp frequency modulation signal; the phase-controlled synthetic aperture dynamic focusing module is used for realizing + / -60-degree deflection and sub-wavelength level focusing of acoustic beams; the nonlinear harmonic enhancement module is used for exciting a crack nonlinear effect by superposing 1-2MHz fundamental waves; and a time-space-frequency three-domain data fusion module. According to the method, signal-to-noise ratio collapse caused by the diffraction effect in a traditional method is overcome, more importantly, the system has low-frequency penetrability and high-frequency resolution at the same time due to 80%-120% of broadband coverage of chirp frequency modulation signals, the diffraction signal gain is increased by 20 dB or above, a near-surface blind area is compressed to be within 0.2 mm, and the system can be applied to the field of radar imaging. And the core pain point of missing detection of the near-surface microcracks of the thin-wall component is solved.
Owner:ANHUA PRECISION TECH (SUZHOU) CO LTD

TGV drilling system and method based on space-time modulation Bessel beam

The invention relates to the technical field of laser micromachining, in particular to a TGV drilling machining system and method based on a space-time modulation Bessel beam, an initial laser beam is output through a laser device, the initial laser beam is modulated into a dynamic pulse sequence through a pulse chirp regulation and control module, axial energy attenuation is compensated, a machining subsystem generates the Bessel beam, and the TGV drilling machining system and method based on the space-time modulation Bessel beam are obtained. The angle is finely adjusted in real time through piezoelectric driving, and a dynamic spatial light modulator loads an exponential decay type phase mask, so that light beam airspace shaping, non-diffraction light beam generation, pulse time sequence and phase parameter synchronous control and high-peak power pulse array are realized, and finally, integrated micro-perforation and channel modification of the glass substrate are realized; and the machining efficiency and precision are obviously improved.
Owner:深圳市圭华智能科技有限公司

Quadrature chirp generation

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

Cable defect positioning method, system, equipment, medium and product

The invention relates to the technical field of power systems, and discloses a cable defect positioning method, system and device, a medium and a product, and the method comprises the steps: taking a Gaussian envelope linear chirp signal as an initial incident signal for frequency domain reflection, optimizing the signal characteristic parameter of the initial incident signal, obtaining an incident signal, and carrying out the positioning of a cable defect. The method comprises the following steps: exciting a target cable through an incident signal, obtaining a reflection signal on a preset measuring point of the target cable, respectively carrying out time-frequency conversion on the incident signal and the reflection signal to obtain an incident time-frequency domain signal and a reflection time-frequency domain signal, and obtaining a time-frequency domain signal and a reflection time-frequency domain signal on the basis of a cross-correlation function. The peak position of a cross-correlation function is determined through the incident time-frequency domain signal and the reflected time-frequency domain signal, the signal propagation defect time delay of the target cable is determined according to the peak position of the cross-correlation function, and the defect position of the target cable is determined according to the signal propagation defect time delay and the propagation speed of the incident signal. Therefore, surrounding signal interference can be filtered out, and the accuracy of cable defect positioning is improved.
Owner:GUANGDONG POWER GRID CO LTD +1

Downlink wake-up receiver implementation method and system based on chirp modulation

The invention provides a chirp modulation-based downlink wake-up receiver implementation method and system, and the method comprises the steps: S1, transmitting a preset wake-up frame to achieve the synchronization with terminal equipment before a transmitter of a wake-up receiver transmits a data frame, the wake-up frame comprises a pure carrier of a preset frequency, a lead code, and a terminal device address sequence and a data sequence based on Manchester encoding; s2, the transmitter generates a baseband signal conforming to a radio frequency front-end mode of the receiver through the wake-up frame, and the baseband signal is subjected to up-conversion and then transmitted in a 433MHz frequency band; and S3, the terminal equipment monitors a channel at any time, demodulates the wake-up frame through envelope detection and intermediate frequency amplification, demodulates a data frame, and finally synchronously sends a wake-up signal and data obtained through demodulation to a post-stage circuit. According to the invention, by designing the wake-up sequence and manufacturing the wake-up circuit, asynchronous wake-up with ultra-low power consumption is realized for the Internet of Things terminal equipment.
Owner:SHANGHAI JIAOTONG UNIV

Underwater acoustic signal communication and positioning integrated method

The invention discloses an underwater acoustic signal communication and positioning integrated method. The existing method does not jointly consider the problem of channel resource occupation caused by integration of communication and positioning. According to the method, mutually orthogonal Chirp subcarriers are used as communication signals, meanwhile, long Chirp signals are used as pilot frequency, and the pilot frequency and the communication signals are overlapped together to be sent at a sender, so that extra channel overhead caused by additional pilot frequency is saved, and the signal sending time interval is shortened. A receiver uses a plurality of pilot signals to perform joint Doppler estimation and compensation and time of arrival estimation, and the result of the time of arrival estimation is used for a positioning system and a communication system on the one hand. According to the demodulation mode, correlation calculation is carried out by using different Chirp subcarriers, and symbol demodulation is carried out according to correlation values. According to the communication and positioning integrated waveform design method, the signal sending time interval can be shortened, the system complexity can be reduced, and good communication performance is achieved.
Owner:ZHEJIANG UNIV

Ultra-wideband femtosecond optical parametric oscillator capable of being quickly tuned

The invention discloses an ultra-wideband femtosecond optical parametric oscillator capable of being quickly tuned, and relates to the technical field of optical parametric oscillators. The oscillator comprises a frequency doubling device, an optical parametric oscillator resonant cavity device and a dispersion compensation chirp mirror pair module. According to the invention, the original phase matching bandwidth is further broken through by adopting a non-collinear phase matching mode that the transmission included angle between the pump light and the signal light is 2.5 degrees, and rapid wavelength tuning can be realized only by finely tuning the cavity length under the condition that the angle of the nonlinear crystal is not adjusted; the broadband tunable optical parametric oscillator can break through the bottlenecks in the aspects of wavelength tuning range, wavelength tuning speed and the like of the existing near-infrared optical parametric oscillator, and provides a novel light source with larger wavelength tuning range and higher tuning speed for the fields needing broadband tunable light sources, such as spectroscopy, micro-nano processing, optical frequency combs and the like.
Owner:TIANJIN UNIV

Anti-multipath and anti-frequency offset satellite communication method based on chirp spread spectrum modulation joint architecture

The invention discloses an anti-multipath and anti-frequency offset satellite communication method based on chirp spread spectrum modulation joint architecture, and relates to the technical field of satellite or data chain communication, the method comprises the following steps: mapping input K bit information into a modulation symbol K, K belongs to {0, 1,..., N-1}; s02, a corresponding chirp baseband signal s [n] is generated according to the modulation symbol K, and the expression of the chirp baseband signal s [n] is as follows: n = 0, 1,..., N-1; and S03, carrying out digital-to-analog conversion on the chirp baseband signal. According to the invention, through integrated design of spread spectrum and modulation depth, and by use of the complete orthogonal autocorrelation characteristic of chirp signals and an FFT demodulation mechanism, the problems that a traditional architecture has significant bottlenecks in the aspects of resource efficiency, dynamic adaptability, anti-interference capability and the like and is difficult to meet high-performance communication requirements in a high-speed moving and complex multipath scene are effectively solved; the anti-multipath and anti-Doppler performance is significantly improved, and the calculation and resource overhead of the receiving end is greatly reduced.
Owner:NANJING TIANJI YIDA COMM TECH CO LTD

Low earth orbit satellite communication initial time frequency offset estimation method

The invention provides a low earth orbit satellite communication initial time frequency offset estimation method, and belongs to the technical field of satellite communication. When satellite communication initial time-frequency offset estimation is carried out, initial time-frequency offset coarse estimation is firstly completed based on a first auxiliary synchronization signal, time-frequency offset coarse compensation is carried out on a received signal by using an estimation result, then initial time-frequency offset fine estimation is further completed based on a second synchronization signal, and the compensated signal is sent to a demodulation module for demodulation. The two-step time-frequency offset estimation method provided by the invention combines the advantages of the symmetric Chirp reference signal and the pseudo code sequence for time-frequency offset estimation, can realize rapid and accurate time-frequency offset estimation in a large-frequency offset scene, and improves the performance of a low-orbit satellite communication system.
Owner:THE 54TH RESEARCH INSTITUTE OF CHINA ELECTRONICS TECHNOLOGY GROUP CORPORATION

Modulation for a frequency modulated continuous wave radar system

A mechanism for generating a modulation signal for use in a radar system. The modulation signal includes a sequence of chirps. Each chirp includes an active period, a transition period and an idle period. During the active period, the frequency of the chirp moves from a start frequency to an end frequency. During the transition period, the frequency of the chirp moves towards the start frequency of the next chirp. The rate of change of the frequency, during the transition period, is different for different chirps of the modulation signal.
Owner:INFINEON TECHNOLOGIES AG

Dual-index modulation radio frequency division multiplexing (AFDM) imitated AFDM communication method

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.
Owner:XIAN UNIV OF SCI & TECH

Injection current modulation for chirp signal timing control

ActiveUS12523745B2Pulse automatic controlAngle modulationRadar systemsHigh bandwidth
A radar system injects a calibrated current at a signal generator during a reset portion and acquisition portion of each chirp period. The signal generator employs “gear-switching” to reduce PLL bandwidth during an acquisition phase and to increase the phase lock loop (PLL) bandwidth during a reset phase. By employing gear switching to change the bandwidth of the PLL circuit during the different portions of each chirp period, the length of the reset period is reduced, thus improving overall efficiency of the radar system while maintaining good performance.
Owner:NXP BV

Wavelength controller and system for a tunable laser

According to an aspect of the present inventive concept there is provided a laser system for generating a frequency modulated continuous wave, FMCW, light signal, the system comprising: a tunable laser for generating the FMCW light signal; an optical measurement unit configured to receive a portion of the FMCW light signal, and to output, via an optical hybrid coupler, at least two angle diversity signals based on a difference between a first and second signal formed by splitting the portion of the FMCW light signal wherein the second signal is delayed relative to the first signal, wherein a pair of signals of the at least two angle diversity signals have a fixed phase shift relative to each other; and a control unit configured to: receive the at least two angle diversity signals, estimate, based on the at least two angle diversity signals, a compensation needed for adjusting a non-linearity of a frequency chirp of the tunable laser, and output a corresponding control signal to the tunable laser, wherein the control signal is configured to improve a linearity of the frequency chirp.
Owner:STICHTING IMEC NEDERLAND

Human respiration and heartbeat signal estimation method based on multi-channel millimeter wave radar

A human body breathing and heartbeat signal estimation method based on a multi-channel frequency modulation continuous wave millimeter wave radar (FMCW) is characterized by comprising the following steps of (1) obtaining an intermediate frequency signal of a multi-channel frequency modulation continuous wave millimeter wave radar (FMCW) system, (2) carrying out distance dimension FFT and phase extraction and unwrapping on a Chirp intermediate frequency signal channel by channel, and (3) carrying out phase extraction and unwrapping on the Chirp intermediate frequency signal channel by channel. (3) calculating signal energy of interested breathing and heartbeat frequency bands in the phase time sequence under all distances, and weighting amplitudes of all distance dimension FFT under all distances to realize accurate positioning of a human body target, and (4) regarding the phase time sequence under the accurate distance and the adjacent distance of each channel as potential multipath signals, and performing fusion enhancement on the signals to realize accurate positioning of the human body target. And (5) processing the enhanced phase time sequences of the channels on the basis of multivariate variational mode decomposition, separating and estimating respiratory signals and heartbeat signals of the human body, and calculating an average respiratory rate and an average heart rate in an observation time period.
Owner:NANJING UNIV

Fractional frequency division frequency synthesizer with output signal phase synchronization and frequency modulation continuous wave functions

The invention discloses a fractional frequency division frequency synthesizer with output signal phase synchronization and frequency modulation continuous wave functions, and the basic structure is a charge pump phase-locked loop. Comprising a phase frequency detector, a first charge pump, a second charge pump, a low-pass filter, a voltage-controlled oscillator, a first buffer, a second buffer, a two-frequency divider chain, an IQ undersampling circuit, a local oscillator generator, a programmable multimode frequency divider, a Delta-Sigma modulator (DSM), a first selector, a second selector, a third selector, a tracking phase accumulator, a numerical control oscillator, an accumulation phase difference register and an atan2 logic circuit. The device comprises a main phase control circuit, a phase adjusting circuit, an enabling control circuit, a waveform generator and a serial peripheral interface. The decimal frequency-division frequency synthesizer can be applied to a general-inductance integrated system, ensures that output signals provided by a plurality of decimal frequency-division frequency synthesizers are consistent in phase in a multi-channel radio frequency transceiving system adopting a multi-chip splicing mode, and can also be applied to the general-inductance integrated system as a sensing signal source; and the speed and the distance of an object can be quickly sensed by the high linearity and the quick chirp capability of an output signal. The decimal frequency division frequency synthesizer is applied to a linear frequency modulation continuous wave radar system, initial phase synchronization can be carried out firstly, then frequency continuous modulation is carried out, and measurement errors can be eliminated. In view of functional similarity of partial modules of the synchronous loop and the FMCW loop, such as a phase frequency detector, a charge pump, a voltage-controlled oscillator and the like, the modules can be shared, so that the power consumption and area cost of the system are remarkably reduced.
Owner:NANJING UNIV OF POSTS & TELECOMM

Ship signal adaptive time-frequency analysis method based on instantaneous frequency direction self-adjustment

ActiveCN120724140AChirplet transformFrequency meter
The invention discloses a ship signal adaptive time-frequency analysis method based on instantaneous frequency direction self-adjustment. The ship signal adaptive time-frequency analysis method comprises the steps of collecting ship signals to be subjected to time-frequency analysis and performing short-time Fourier transform; estimating the instantaneous frequency of the ship signal based on short-time Fourier transform time-frequency distribution in combination with time-frequency narrow-band features; calculating the instantaneous frequency and the optimal window length after smoothing; segmenting the smoothed instantaneous frequency in time, calculating time-frequency domain direction pre-guidance of each time period, and constructing a Chirp atomic direction over-complete dictionary; segmenting the ship signal in time, and calculating the matching direction of the ship signal in each time period so as to calculate and improve Chirplet transformation time-frequency distribution; and calculating the optimal short-time Fourier transform in combination with the optimal window length, and correcting and improving Chirplet transform time-frequency distribution. According to the method, the robustness of short-time Fourier transform and the anisotropy of improved Chirplet transform are utilized at the same time, and time-frequency distribution with high robustness and high time-frequency resolution is obtained.
Owner:南京畅淼科技有限责任公司

Chirp spread spectrum photon terahertz communication sensing integrated system

The invention discloses a chirp spread spectrum photon terahertz communication perception integrated system. The system comprises a coherent light source module used for generating two beams of coherent single-frequency optical carrier signals; the signal modulation module is used for generating a baseband chirp spread spectrum communication sensing integrated signal and modulating the signal to one beam to form a carrier signal; the integrated signal transmitting module is used for taking the other beam of single-frequency optical carrier signal as an optical local oscillator signal, and after the optical local oscillator signal is coupled with the carrier signal, a terahertz communication sensing integrated signal is generated and radiated through optical down-conversion; the communication receiving module is used for performing frequency conversion and demodulation on the received terahertz communication sensing integrated signal and recovering communication information in the signal; and the radar receiving module is used for performing de-chirp and target information estimation on the received terahertz communication sensing integrated signal. According to the system, the advantages of a photon terahertz architecture are fully exerted, and an ultra-wideband chirp spread spectrum integrated signal is generated, so that a communication sensing integrated system with high spread spectrum gain and high energy efficiency is realized.
Owner:ZHEJIANG UNIV

Chirp interval modulation backscatter communication method and system based on variable-length scrambling codes

The invention discloses a chirp interval modulation backscatter communication method and a chirp interval modulation backscatter communication system based on variable-length scrambling codes, which mainly solve the problems of high power consumption of backscatter labels and high system deployment cost in the prior art. According to the scheme, a sending end sends an environment LoRa signal; the backscattering label modulates information to be sent to an environment LoRa signal in a time interval modulation mode, and modulates a variable-length scrambling code to an anchor symbol; a receiving end performs frequency shift compensation on the backscattering signal by adopting a frequency shift compensation method, demodulates the backscattering signal by combining a sliding window with a variable-length scrambling code, intercepts a backscattering signal sample through the sliding window, and performs de-spreading and fast Fourier transform (FFT) on the signal in the window; the position of an anchor symbol is determined by detecting the maximum value of an FFT peak value, information sent by the backscattering label is recovered from the position of the anchor symbol, and data demodulation is completed. On the premise of keeping demodulation reliability, the power consumption of the tag is effectively reduced, the deployment cost of a backscatter communication system is reduced, and the method can be used for ultra-low power consumption Internet of Things communication.
Owner:XIDIAN UNIV

Thin film thickness rapid measurement method based on Chirp-Z transformation

The invention discloses a method for rapidly measuring the thickness of a thin film based on Chirp-Z transformation. The method comprises the following steps: 1) collecting spectral data; 2) data preprocessing; 3) CZT (linear frequency modulation Z transform) parameter configuration and CZT frequency spectrum calculation; according to the method, after the processed data collected by the spectrograph are received, data preprocessing is carried out, spectral analysis is carried out through Chirp-Z transformation, the spectrum peak value is obtained for accurate positioning, the film thickness is calculated through the effective refractive index, and therefore efficient and high-precision film thickness measurement is achieved.
Owner:YIYING TECH (SHANGHAI) CO LTD

Ant colony optimization energy focusing cable insulation damage positioning method and device

The invention discloses an ant colony optimization energy focusing cable insulation damage positioning method and device, and relates to the technical field of cable detection engineering, and the method comprises the steps: generating a Gaussian envelope linear frequency modulation chirp detection signal, injecting the detection signal into a to-be-detected cable, and collecting an incident signal and an echo signal containing a reflection component; constructing a parameterized time-frequency analysis kernel function family under a Cohen type time-frequency distribution framework, and searching and optimizing kernel parameters by using an ant colony optimization algorithm; and calculating the time frequency distribution and energy-time curve of the signal based on the energy focusing time frequency analysis kernel function obtained through optimization, extracting the arrival time corresponding to an energy peak value, and realizing cable insulation damage positioning according to the reflection time delay and the propagation wave velocity. According to the method, energy peak focusing and peak position stability are enhanced while cross terms are restrained, defect positioning precision and robustness are remarkably improved, and the method is suitable for engineering online detection and automatic implementation of cable insulation damage.
Owner:HOHHOT POWER SUPPLY BUREAU OF INNER MONGOLIA POWER GRP CO LTD

Intracranial SEEG electroencephalogram data analysis method and system based on artificial intelligence

The invention discloses an intracranial SEEG electroencephalogram data analysis method and system based on artificial intelligence, and relates to the technical field of data analys.The method comprises the steps that original electroencephalogram signals are obtained, and electrode space coordinates and imaging information are synchronized; extracting robust features in a time-frequency domain through synchronous extrusion in combination with learnable chirp and multi-resolution attention; according to the electrode coordinates and the anatomical topology, topology sensing alignment is executed, and an anatomical function diagram is constructed; performing continuous time evolution modeling on a node state through a graph neural continuous dynamic structure, and introducing an energy conservation and event jump mechanism to realize focus transmission chain inference; estimating orientation information in different physiological contexts, and screening a stable direction as a prior constraint; and outputting a continuous risk curve according to propagation embedding, and generating a coverage-controllable confidence interval through online conformal calibration. Energy consistency, causal stability and space-time continuous modeling of SEEG signals can be realized, and the accuracy and interpretability of electroencephalogram focus recognition and clinical risk assessment are improved.
Owner:XUANWU HOSPITAL OF CAPITAL UNIV OF MEDICAL SCI

Method and system for identifying blade tip timing vibration measurement signal parameters under time-varying rotating speed

The invention relates to the field of rotor blade non-contact state monitoring, in particular to a blade tip timing vibration measurement signal parameter identification method and system under a time-varying rotating speed. Comprising the following steps: constructing a matrix Chirp signal model; performing initial frequency pre-analysis based on a block orthogonal matching pursuit method to obtain an estimated value; defining a range interval of initial frequency analysis and an analysis range of a frequency modulation slope by taking the estimated value as a center, and obtaining an orthogonal matching pursuit result based on a matrix Chirp signal model and a block orthogonal matching pursuit method; and according to a matching tracking result, calculating to obtain a vibration amplitude. According to the method, the frequency modulation slope is introduced to serve as an additional parameter, the change trend of the frequency along with time is reflected, the vibration rule of the blade under the centrifugal stiffening effect can be more truly described, and an accurate physical basis is provided for analysis of non-stationary signals.
Owner:CHANGAN UNIV

Technologies for programmable microring resonators

PendingUS20250306427A1Non-linear opticsMechanical engineeringFree carrier density
Techniques for programmable microring resonators are disclosed. In an illustrative embodiment, microring resonator is coupled to a waveguide. Due to process variations, the coupling rate between the microring resonator and the waveguide can vary. In order to tune the coupling regime between the microring resonator and the waveguide, a diode that forms part of the microring resonator can be forward biased, increasing the free carrier density and absorbing some of the light in the microring resonator. The forward biased diode can be used for various applications, such as to control the quality factor of the microring resonator, control a chirp on the light, and / or impart a blueshift to the microresonator.
Owner:INTEL CORP

Enhanced integrated sensing and communications waveform

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a transmitter node may determine a set of parameters for a waveform to be transmitted by the transmitter node, wherein the waveform is to use an allocated bandwidth that is larger than a sweeping bandwidth of a frequency modulated continuous wave (FMCW) chirp. The transmitter node may transmit the waveform according to the set of parameters. Numerous other aspects are described.
Owner:QUALCOMM INC

Communication sensing integrated system based on non-orthogonal AFDM (Alternating Frequency Division Multiplexing)

The invention belongs to the technical field of wireless communication, and particularly relates to a communication sensing integrated system based on non-orthogonal AFDM (Alternating Frequency Division Multiplexing). According to the system, a bandwidth compression factor is introduced into an AFDM framework to construct a non-orthogonal waveform, and controllable overlapping between chirp subcarriers is realized, so that the spectrum utilization rate is improved, and the robustness of the system under a high-speed dynamic channel is enhanced. And a receiving end realizes reliable information recovery through maximum likelihood detection, and processes echo signals in combination with a two-dimensional parameter estimation algorithm so as to realize high-precision sensing of the target distance and speed. The system has good anti-Doppler capability and perception precision performance, and is suitable for communication perception fusion application in a high-speed mobile scene.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Vehicle-mounted multi-radar system interference suppression method, system and platform based on frequency hopping frequency modulation continuous waves

The invention discloses a vehicle-mounted multi-radar system interference suppression method, system and platform based on frequency hopping frequency modulation continuous waves, and the method comprises the steps: arranging at least one front radar and four corner radars on a vehicle, and enabling the field angles of the radars to have an overlapping region; wherein the waveform transmitted by each radar consists of N linear frequency modulation continuous waves, and the duration of each chirp is T microseconds; the chirp starting frequency of each radar changes along with time, so that N1 chirp is greater than or equal to 1 and less than or equal to N when each radar passes through N1 chirp; the initial frequency is increased or decreased by a fixed step delta F, and the average frequency hopping step is delta F / N1; according to the system and the platform corresponding to the method, the chirp initial frequency is dynamically adjusted and the time delay is accurately controlled, so that the interference-free cooperative work among the multiple radars is realized, the distance resolution, the speed resolution and the signal-to-noise ratio are remarkably improved, and the system and the platform have the advantages that the interference-free cooperative work among the multiple radars is realized. And meanwhile, hardware design is simplified.
Owner:SHENZHEN CHENG TECH CO LTD

In-situ diagnostics of microwave interconnects for quantum computers

A system comprises a digitally programmable frequency chirp generator configured to generate a frequency chirp, an attenuator coupled to the digitally programmable frequency chirp generator and a directional device integrated into a cryogenic circuit configured to control superconducting qubits and coupled to the digitally programmable frequency chirp generator. The directional device comprises a main arbitrary waveform generator and an on-chip programmable self-interference canceller.
Owner:INTERNATIONAL BUSINESS MACHINE CORPORATION