11 results about "Time gating" patented technology

The embodiment of the invention provides a quantum enhanced single-photon OTDR method, system and device and a medium, and belongs to the technical field of optical fiber sensing. The method comprises the following steps: constructing an outer time gating parameter group according to measurement distance segment information; controlling the single-photon detection link to execute segmented gating in the round-trip time window of each measurement pulse based on the outer time gating parameter group; establishing a corresponding relationship based on the single photon counting data and the external time gating parameter group, terminating counting accumulation of the corresponding distance grids when each distance grid meets a preset statistical condition, and constructing a distance grid counting sequence for representing the on-way scattering characteristic of the optical fiber; counting normalization processing and segmentation result splicing processing are sequentially executed based on the distance grid counting sequence, and reflection event information corresponding to the whole optical fiber process is output. According to the scheme of the invention, through cooperative processing of segmented gating and statistical normalization, weak scattering information and a strong reflection structure in the whole process of the optical fiber present more stable and more continuous reflection event distribution under the same counting frame.

This application provides an optical sensing device, including a light emitter and a light receiver. The light emitter sequentially emits light pulses; the light receiver includes multiple effective pixels, each of which includes multiple physical pixels. Each effective pixel is configured such that it is activated only in one corresponding time partition out of multiple time partitions. The physical pixels are used to receive light pulses reflected back from an object from the emitted light pulses and convert the received light pulses into electrical signals. Each light pulse period corresponds to one of the multiple time partitions. This application can improve the tolerance of the optical sensing device to ambient light, thereby increasing the maximum outdoor ranging distance. Compared with traditional time gating schemes, it can also improve the frame rate.

The invention relates to an underwater long-distance high-precision three-dimensional imaging method and system. The method comprises the following steps: S100, obtaining n gating images of different time gates; s200, respectively inputting the n gating images of different time gates into n encoders with independent parameters for feature extraction to obtain n groups of feature representations; s300, fusing the n groups of feature representations by adopting a cross-level feature fusion mechanism to generate fused features; and S400, the fusion features are decoded, and a pixel-level depth map is generated. Through the arrangement, the feature extraction capability and the depth reconstruction precision are remarkably improved, and complementary information of multiple images is effectively integrated through a cross-level feature fusion mechanism.

This invention discloses a method for generating and evaluating Doppler simulation data for low-Earth orbit (LEO) satellites. By employing source-end discrete-time gating, the system is forced to directly block output when the time deviation exceeds 1 ms, fundamentally severing the error coupling path and ensuring the purity of the output data. In the inertial frame velocity synthesis, an explicit Earth rotation-related velocity correction term is introduced, enabling even stationary receivers to accurately reflect their motion in inertial space. An elevation-angle-weighted noise model is used to accurately simulate the physical phenomenon of sharp link deterioration in LEO satellites at low elevation angles, realistically reflecting the tracking and loss-of-lock behavior of receivers in complex geometric environments. Terminal physical consistency verification is introduced. By comparing the distance change rate calculated in the velocity domain with the distance rate of the position domain derivative in real time, a rigorous closed-loop feedback mechanism is constructed, which can automatically identify and eliminate abnormal data caused by ephemeris jumps or numerical divergences, significantly improving the engineering confidence of the simulation data.

The present disclosure provides an automatic optimization method of a full-automatic ultrasonic detection process scheme, which automatically imports the test block groove parameters and reflector position information, generates an initial focusing rule by computer, accurately positions the mechanical scanner and automatically finds the highest amplitude position of each reflector, then adaptively adjusts the key ultrasonic parameters such as the transmitting / receiving wafer and the angle according to the channel type, so that the main amplitude reaches the standard requirement and is positioned to the center of the time gate, while the coverage amplitude of the adjacent channel is intelligently checked and optimized, and the TOFD channel and the coupling channel are specially set with parameters, finally realizing the full-automatic, high-precision and high-efficiency whole process of test block calibration, effectively avoiding the errors and low efficiency problems caused by the difference in operation experience in the traditional manual calibration, significantly improving the consistency and reliability of the detection, and completely eliminating the detection blind area, providing complete data support for the evaluation of the welding quality.

Methods and apparatuses are described herein for providing fine-grained QoS rules within UE Policies. A network entity may receive triggers to update the policies of a user equipment (UE) with parameters based on input such as input from a third party. The network entity may derive fine-grained quality of service (QoS) rules and corresponding QoS Profiles and delivers them to the UE using a UE Policy container via the Non-Access Stratum (NAS). The fine-grained rules may comprise: a destination fully qualified domain name (FQDN) or uniform resource locator (URL), an Application ID, a User Route Selection Policy precedence value, etc. The fine-grained rules also provide mechanisms for time gating or volume gating. The UE may request new QoS treatment resulting in UE Policy update and may use the information in the fine-grained QoS rules when establishing or modifying PDU Session to apply QoS Flow Identifier (QFI) marking.

The application provides a heterodyne distributed acoustic wave sensing system based on frequency shift time gating and a demodulation algorithm, and belongs to the technical field of distributed acoustic wave sensing. A light coupling module divides continuous laser into two paths of signal light and local oscillator light. A light modulation module sequentially performs pulse modulation and frequency shift modulation on the signal light, and outputs the modulated light pulse. A sensing optical fiber receives the light pulse output by the light modulation module, and generates a backscattering signal based on the back Rayleigh scattering effect. A light mixing module coherently mixes the backscattering signal and the local oscillator light. A photoelectric detection module converts the coherently mixed light signal into an electric signal. A signal processing unit collects the electric signal and extracts vibration information at different positions of the optical fiber through a phase demodulation algorithm. The application realizes synchronous integration of pulse and frequency shift modulation, optimizes the demodulation algorithm, improves the system stability, sensing accuracy and response efficiency, reduces the hardware cost and energy consumption, and is suitable for multi-scene application through innovative light path design and signal processing strategy.

The application discloses a remote sensing image change detection method based on space-time feature fusion. Based on the cross-time gating mechanism and the cross-scale attention mechanism, the application introduces a time feature fusion module and a space feature fusion module in the remote sensing image change detection task. In the time feature fusion module, the cross-time gating mechanism is used to guide the selective enhancement of the interesting change and the suppression of the non-interesting change, so as to obtain an accurate change representation. The deepest change representation is fused with other shallow change representations through the space feature fusion module. Based on the cross-scale attention mechanism, the high-level representation is used to guide the low-level representation to model the context, so as to enhance the feature expression ability of the low-level representation, capture the fine-grained information of the interesting change and better restore the spatial details of the change representation. The application provides a new solution for the feature fusion mechanism in the change detection task under the complex remote sensing image background, and can effectively improve the change detection effect.

This invention relates to a lidar detection and imaging method and apparatus. The method includes emitting a laser pulse, preprocessing the returned signal and calculating approximate distance and time, continuously measuring to narrow down the target's range, and then iterating until the time interval between two measurements is approximately the same, at which point time-gated locking is achieved, and target detection begins. Compared with existing technologies, this invention has the advantages of providing high-quality time gating in a very short time, thereby increasing the accuracy of radar detection.

This invention discloses a method and system for early warning of abnormal behavior of dormitory personnel based on millimeter-wave radar. It combines three-dimensional spatial semantic modeling to divide the area into beds, desktops, and floors, and introduces a time gating mechanism to filter normal sleep and accurately determine abnormal prolonged lying-down states. By extracting the trajectory curvature probability distribution entropy value and round-trip repetition degree within specific semantic regions, it effectively overcomes the limitations of existing technologies in objectively quantifying and accurately identifying latent behavioral patterns such as student anxiety in real-life scenarios. A multi-source evidence fusion framework is constructed, which dynamically weights radar motion intensity evidence and acoustic energy evidence by calculating the spatial consistency between the radar target and the audio source location. Furthermore, by utilizing synthesis rules that include conflict handling, it effectively suppresses false alarms, greatly improving the accuracy and reliability of fall detection and violent conflict identification in complex practical applications.

The invention belongs to the technical field of photon detection, and particularly relates to a THz photon counting detection system based on cascade frequency up-conversion, which comprises a first pump light source, a second pump light source, a first beam combiner, a first nonlinear crystal, a light splitting unit, a second beam combiner, a second nonlinear crystal, a light shaping device, a space photon counting detector, a time gating and a space gating. The first nonlinear crystal upconverts THz wave frequency into a near-infrared light signal and generates spontaneous parametric upconversion fluorescence noise consistent with time, space and spectrum characteristics of the signal, and the signal and the noise are mixed, so that the unit type SPD fails. According to the technology, the cascade frequency of a near-infrared signal is up-converted to visible light, signal-noise photons are spatially separated through a light shaping device, and photon counting detection of the signal is realized by combining a space photon counting detector with a mature visible light wave band with space-time coincidence measurement, so that room-temperature photon counting detection of THz waves is realized.