11 results about "Weak pulse" patented technology

This invention discloses a method for preparing a flexible ion piezoelectric material, comprising the following steps: (1) preparation of a click chemical reaction prepolymer: polyethylene glycol diacrylate as an olefin monomer is mixed uniformly with a multi-thiol monomer to form a prepolymer; (2) polyethylene glycol, an ion medium, and an alkaline catalyst are added to the prepolymer, mixed uniformly in an ice-water bath, injected into an inverted structure mold, and heated to solidify to obtain a flexible ion piezoelectric material. The ion piezoelectric material prepared by the method of this invention has high sensitivity and high stability, and can generate a significant electrical signal under weak pulse pressure (<0.1 kPa), while maintaining zero volatilization and zero leakage for more than 30 days, thereby ensuring long-term signal stability.

The application discloses an integrated amplifier circuit, which comprises an input signal conditioning module, a front-stage signal amplification module, an intermediate signal amplification module and a power output module connected in sequence. The input conditioning module is isolated from direct current through double-coupling capacitors, and impedance matching and current-voltage conversion are completed through resistors, so that direct current interference and input waveform distortion are eliminated. The front stage adopts a double-NPN triode amplification structure matched with a diode voltage-stabilized bias to realize primary amplification of weak pulse signals. The intermediate stage completes secondary signal amplification through combined triodes and relies on a compensation capacitor to suppress self-oscillation. The power output module adopts a double-NPN triode push-pull structure to improve signal driving capacity and simultaneously has overload protection and direct current isolation output functions. The circuit has the advantages of simple structure, strong anti-interference performance, excellent amplification precision and driving performance, and can effectively improve the problems of distortion and easy self-excitation of traditional circuits, and is suitable for weak pulse signal amplification scenes.

A quantum key distribution system may include a transceiver including a state randomizer to impart a random state transformation to one or more qubits of a generated faint pulse and a quantum bit encoder to reflect the faint pulse back to the transceiver with one or more encoded bits. The transceiver may receive a return pulse through the communication channel, where the state randomizer reverses the random state transformation. The transceiver may include a set of two detectors to measure the return pulse at time-gated timeslots associated with possible paths of the return pulse. Reception of the faint pulse from the quantum bit encoder as the return pulse triggers a detector in one or more known time-gated timeslots determined based on the random state transformation, while reception of a faked-state pulse results in a non-zero probability of triggering of a detector in a different time-gated timeslot.

The present application relates to a kind of impulse echo positioning cable detector, it includes: integral circuit array, each integral circuit unit of integral circuit array includes an integral capacitor;Switch array is used to select the single integral circuit unit in integral circuit array;Test control module is used to divide echo detection period into multiple time slices, and each time slice is associated with a specific integral circuit unit, then each integral circuit unit is selected in turn according to time sequence, and the echo signal of the same time slice of multiple rounds of echo detection period is introduced into the same integral circuit unit to accumulate;Sampling module is used to read out the signal value cached by each integral circuit unit, and the time sequence waveform of echo signal is recovered;And data processing module is used to determine the arrival time of echo pulse.The present application also provides a corresponding weak pulse signal detection method.The present application can detect extremely weak echo signal, so that transmission impedance uneven point can be detected in super long distance.

The invention discloses a microwave photon enhancement device for transient weak pulse spectrum sensing and a sensing method. The microwave photon enhancement device comprises an electro-optical modulation module, a first transient pulse replication branch, a second transient pulse replication branch and an autocorrelation detection module. A to-be-measured signal forms a first carrier signal at the electro-optical modulation module modulating the carrier light source; the first pulse copy loop copies the first carrier signal to form a first pulse stream signal; the second pulse copy loop copies the first carrier signal, and forms a second pulse stream signal after passing through the optical delayer; the self-correlation detection module carries out self-correlation operation on the first pulse flow signal and the second pulse flow signal. According to the microwave photon enhancement device for transient weak pulse spectrum sensing and the sensing method, the pulse replication loop is adopted to perform periodic replication on transient extremely narrow pulses, instantaneous self-correlation operation of a radio frequency domain of an analog signal to be detected is realized through the microwave photon link, the signal-to-noise ratio of the signal to be detected is improved, and the sensitivity of an instantaneous frequency measurement system is improved.

The invention discloses a non-contact heart rate estimation method fusing physical prior and Transform, and the method comprises the steps: designing a double-branch spatial-temporal feature fusion module which is used for separating interference from the source and enhancing a weak pulse wave signal; the dual-branch spatio-temporal feature extraction module is configured to separate interference signals and enhance pulse wave signals, and comprises a motion branch and an appearance branch. According to the invention, a combined architecture of convolution and Transform is designed, and a relative position coding module is introduced. According to the method, the normalized frame difference is introduced to serve as input of the motion branches, appearance branch feature fusion is combined, and noise interference caused by illumination and non-rigid motion is effectively restrained. The high-precision global modeling of a weak heart rate change mode is realized by combining a 3D CNN and a Transform architecture and utilizing a time difference attention mechanism.

According to the spectrum optimization and pulse compression system and method based on solid multi-pass pool post-compression, ultrafast laser pulses output by a laser output module are transmitted back and forth in a spectrum broadening module through an energy regulation and mode matching module, are broadened in a time domain and a frequency domain under the nonlinear effect and the dispersion effect, and are subjected to spectrum optimization and pulse compression; and after being subjected to beam shrinkage and collimation through the light path collimation module, the broadened pulse enters the dispersion compensation module to be subjected to pulse compression. Time-frequency characteristics of laser pulses are measured through the real-time detection module, cross-module multi-parameter collaborative optimization, accurate energy regulation and control, spectrum broadening and dispersion compensation module system parameters are carried out on detection information by adopting the control feedback module, spectrum modulation is inhibited, negative chirp and nonlinear phase distortion of front and rear edges of the pulses are weakened, and the accuracy of the system parameters is improved. And the pulse compression quality is improved. The pulse width of the output compression pulse is close to the Fourier limit, the pulse width is reduced, and the peak power is improved.

The invention discloses a pulse type radio frequency interference judgment method based on multi-domain feature entropy weight fusion, a storage medium and electronic equipment, and the method comprises the following steps: carrying out pulse-by-pulse processing on interference-containing echo data, respectively extracting a time domain statistical center deviation degree feature and a time domain sharpness feature, and extracting a frequency domain kurtosis feature and a frequency domain skewness first-order difference feature, and carrying out pulse-by-pulse processing on the extracted feature; constructing a pulse-by-pulse multi-domain feature vector sequence; then, based on the information entropy theory, adaptive weighted fusion is carried out on the multi-domain features, pulse-by-pulse interference detection scores are obtained, statistical histogram distribution is constructed according to the detection scores, and Gaussian smoothing processing is carried out; further, an OTSU self-adaptive threshold judgment method is adopted for segmentation, and automatic judgment of pulse-containing interference pulses is achieved; and outputting a pulse type interference judgment result. According to the invention, the abnormal characteristics of the pulse-type interference in the multi-domain feature space can be effectively represented without manual threshold setting, and the judgment accuracy and stability under the weak pulse interference condition are improved.

The application discloses a passive wireless pulse current partial discharge sensor and relates to the technical field of partial discharge sensors.The passive wireless pulse current partial discharge sensor comprises a monitor, angle irons are fixedly arranged on the two sides of the monitor, and further comprises a bottom plate which is connected with the monitor through a multi-angle adjusting structure.The multi-angle adjusting structure is used for flexibly adjusting the angle of the monitor and installing the monitor in a required area for current measurement.The monitor detection surface is dynamically adjusted along with the direction of a partial discharge signal source, the capture precision of weak pulse current is remarkably improved, the foldable shielding cover is synchronously unfolded along with the angle adjustment of the monitor, a metal shielding plate and a honeycomb-shaped electromagnetic wave absorbing layer form an "electric-magnetic" double shielding system, the distortion influence of interference signals on current measurement is avoided, and the opening of a swing leaf in the shielding and heat radiating structure is automatically adjusted along with the angle, so that the accurate collection of current signals is realized under stable working conditions, and the reliability of partial discharge monitoring is comprehensively improved.

A receiver for receiving weak light pulses in a discrete-variable encoding quantum key distribution system, includes:an optical coupler having first and second inputs and outputs and is configured to be connected to a quantum channel to receive the weak pulses at the first input, and local oscillator signals at the second input;a local oscillator laser adapted to generate the local oscillator signals,a laser locking system for locking the difference between wavelengths to a fixed value, so that the difference remains constant in time;a synchronizer connected to the local oscillator laser so that the local oscillator laser emits a local oscillator signal at a given time;first and second photodetectors, the first and second photodetectors connected to the first and second outputs, respectively;an electronic circuit configured to obtain a difference signal;a filter adapted to filter the difference signal, generating a filtered signal; anda discriminator.