435results about How to "Improve detection performance" patented technology

This invention relates to one portable X wave section Doppler gas radar signal process method, wherein, the receive sub system processes wide band receive method on signals to form main path amplifier of low noise sound effect tube to form receive system together with reference signal amplifier ad lock phase vibration and stable lock ; adopting wide band for receive within range of 45MHz-75MHz automatically catching and tracing aim signals; Main path amplifier is composed of low noise sound effect, mixture device for selecting echo signal to output middle frequency signal; the reference signal amplifier is composed of mixture device and middle frequency amplifier.

The invention discloses a system and method for detecting language voice frequency, and belongs to the technical field of language signal processing. The system comprises an acoustic feature extraction module, a phoneme identification module, an acoustic confidence calculation module, a language confidence calculation module, a prosodic feature extraction module and a classification discrimination module. Through comprehensive utilization of acoustic confidence, language confidence and prosodic feature information, the detection performance of the system is obviously improved, the system is suitable for the detection of voice frequencies with different lengths and has good detection stability, various non-target language voice frequencies and noise voice frequencies can be processed, the system has good practicability and can be quickly expanded according to the types of non-target languages by providing the acoustic model and the language model of a new language and then re-training a classifier model, so that the system structure has better flexibility and expandability.

The invention discloses a polarization SAR image ship target detection method based on the distribution characteristics of a superpixel scattering mechanism. The method comprises the implementation steps that superpixel segmentation results under different scales are obtained through an SLIC iteration clustering algorithm; the distribution characteristics of the superpixel scattering mechanism are defined; the scattering mechanism distribution characteristic vectors of all the superpixels in a clutter training image and a test image are extracted; clutter training image over-complete dictionaries are constructed; scattering characteristic sparse reconstruction of the test image under the corresponding dictionary is carried out, and a detection statistics image is obtained; by applying an appropriate detection threshold value on the detection statistics image, a binary image of a final detection result is obtained. The method achieves the purpose of detecting ship targets with the distribution characteristics, the ship targets are detected on the superpixel level, the regional distribution characteristics of the scattering mechanism are effectively utilized, and higher robustness is achieved under different signal-to-clutter ratios.

The invention discloses a directional induced polarization real-time advance water detecting device while drilling for tunnel construction. The device comprises a drill bit, a high-strength insulated sleeve while drilling, and a directional induced polarization detection system, wherein the drill bit is connected with the high-strength insulated sleeve while drilling through a connecting bearing, and the directional induced polarization detection system is distributed at the periphery of the high-strength insulated sleeve while drilling. The invention also provides a corresponding directional induced polarization real-time advance water detecting method while drilling for tunnel construction. According to the device and the method disclosed by the invention, the interference of the construction environment is avoided, the detection effect is better, the utilization efficiency of an advance borehole is improved, current orientation is realized, the low resistance at the borehole wall is broken through, the detection range is enlarged, an electrode is protected, and a better coupling contact between the electrode and a rock-soil body is guaranteed.

The invention discloses a portable Terahertz remote sensing detector and a remote detection method. The detector comprises a signal generating device, a detector, a processor and an imaging display device, wherein the signal generating device comprises a Terahertz wave radiation source, a broadband tunable laser and a plasma generator; and the detector comprises a receiving element, a detecting element and a signal modulation circuit. The detection method comprises the following steps of: 1, dividing scanning subregions and pixel points and encoding scanning output frequencies of various scanning subregions; 2, arranging an assembly and generating a remote detection signal; 3, performing two-dimensional scanning; and 4, performing signal analysis processing, namely rapidly imaging and generating a Terahertz wave image with frequency spectrum characteristics, identifying a material type of a tested object, generating a charge coupled device (CCD) image and identifying the shape of the tested object. The detector is reasonable in design, easy to operate, flexible in detection mode, wide in application range and good in detection effect, and can fulfill the aims of rapidly imaging and remotely detecting by combining THz and induced fluorescence spectrum analysis with space imaging.

The present invention belongs to the aerial vehicle positioning, tracking and identification technical field and relates to a passive positioning and identification system for civil unmanned aerial vehicles. The system is composed of three parts, namely, a passive radar, a signal detection and receiving part and a fusion processing part. According to the passive positioning and identification system for the civil unmanned aerial vehicles of the present invention, the passive radar is adopted to detect and position an unmanned aerial vehicle at a low altitude and a low velocity; since the passive radar has a good capability of detecting small targets at low altitudes and low velocities, and therefore, a good unmanned aerial vehicle detection effect can be realized; since the characteristicsof different types of unmanned aerial vehicle remote control and telemetry signals have large differences, so that an unmanned aerial vehicle remote control and telemetry signal detection and receiving analysis method can be adopted to identify unmanned aerial vehicles; the passive radar is adopted to guide the system of remote control and telemetry signal detection and receiving, and therefore,a signal detection and receiving acting distance can be prolonged, and the complexity and cost of signal detection and receiving can be improved; and during work, the entire system does not need to radiate out signals, and therefore, the system is free of electromagnetic pollution and environmentally friendly.

The invention relates to the technical field of radars, and discloses a laser radar and a resolution adaptive adjusting method thereof. The laser radar comprises a shell, a laser ranging unit, a rotary scanning unit, an angle measurement unit and a control and signal processing unit, wherein the laser ranging unit is used for measuring a target distance value of a target object through a laser beam, and sending the target distance value to the control and signal processing unit; the rotary scanning unit is used for changing the propagation direction of the laser beam, so that a laser beam pathcan scan the target object; the angle measurement unit and the rotary scanning unit can coaxially rotate, and the angle measurement unit is used for determining the current angle position of the rotary scanning unit; the control and signal processing unit is used for obtaining the current angle position information of the rotary scanning unit and the corresponding target distance value, and adjusting the current angular resolution according to the angle position information and/or the target distance value corresponding to an existing preset rotation angle of the rotary scanning unit.

The invention discloses a method for detecting a base station feed system on line, a base station system and an antenna suite. The base station antenna system comprises antenna test accessories which are arranged at antenna fixed positions and are used for fixing test terminals; the antenna test accessories comprise fixed test positions which are used for arranging the test terminals and making the direction of polarization of transmitted signals relatively fixed with the direction of polarization of a base station receiving antenna when the test terminals are at the fixed test positions; and the output characteristics of the base station receiving antenna are fixed in a preset error range. By the method, the performance for detecting the feed system is improved; the online performance detection can be immediately and conveniently performed on the whole base station system after the project installation of the whole base station system is completed; and that the base station feed system is in a bad condition can be instantly found and immediately improved to ensure that the base station system for project delivery meets the requirement on design performance.

The invention discloses an approximately optimal radar target detection method against K-distributed clutter plus noise and aims to solve the problem that the prior art is not completely suitable for target detection against K-distributed clutter plus Gaussian white noise. The method comprises steps of: 1) acquiring an echo data matrix, and blocking the echo data matrix; 2) selecting a to-be-detected distance unit zk of the bth echo data block, and calculating the covariance matrix estimator R<k> of the to-be-detected distance unit zk; 3) calculating the carrier noise ratio CNR of the echo data by use of the covariance matrix estimator R<k>; 4) calculating the test statistics xik of the to-be-detected distance unit by use of the CNR and the R<k>; 5) calculating the detection threshold T<xi> according to the false alarm probability; and 6) judging whether the a target exists or not by comparing the size of the test statistics xik and the detection threshold T<xi>. In this way, the target detection performance is improved and the approximately optimal radar target detection method can be used for radar motion detection under the back ground of sea clutter.

The invention discloses a spectrum sensing algorithm based on variational mode decomposition, and solves the problem that a signal at a receiving end is interfered by a noise background in the prior art. The method comprises the following steps of: 1, generating a simulation signal BPSK; 2, taking the mean value of the instantaneous frequencies of the components as a decomposition parameter, determining an optimal mode decomposition number K according to a change curve of the decomposition parameter, and setting an appropriate penalty factor alpha; 3, performing variational mode decompositionon the BPSK signal according to the obtained decomposition parameters; 4, respectively carrying out power spectrum estimation on the obtained L intrinsic modes; 5, taking the ratio of the sum of the spectral line intensities of the intrinsic modes to the sum of intensities of all the intrinsic modes as a test statistic; and 6, comparing the obtained test statistics with a judgment threshold, and making a final judgment. According to the method, the equivalent band-pass filtering characteristic and the Wiener filtering structure of variational mode decomposition are utilized, frequency bands are better divided, and denoising processing is better carried out; and compared with a traditional power spectrum segmented cancellation algorithm, the detection performance can be remarkably improved.

The invention relates to an electrochemical sensor for detecting lead. The electrochemical sensor comprises a glassy carbon electrode, wherein the glassy carbon electrode is utilized as a working electrode in a tri-electrode system, the surface of a detection end of the glassy cabon electrode is modified by a multi-walled carbon nanotube, nano golden particles are deposited on the multi-walled carbon nanotube, and a sulfydryl-modified capturing probe is connected with the nano golden particles; the electrochemical sensor further comprises an aptamer probe, wherein the aptamer probe and the sulfydryl-modified capturing probe are complementally paired to form a double-chain structure. According to the electrochemical sensor for detecting the lead, the aptamer probe is utilized to cover lead ions so as to be separated from the capturing probe, and during the separation, an electrochemical signal to be detected is generated, so that the purpose of detecting the content of the lead ions in the water body is achieved; the electrochemical sensor has the advantages of high sensitivity, excellent selectivity and stability, and the like.

The invention discloses a thermal radiation infrared transmitting and probing integrated device. The integrated device is in the structure that: a silicon substrate provided with a substrate insulation layer is opened with at least one thermal isolation cavity, the thermal isolation cavity is suspended with at least one transmitting unit and at least one probing unit which are adjacent and are arranged side by side, the transmitting unit is connected with the silicon substrate by virtue of at least two supporting arms, and the probing unit is connected with the silicon substrate by virtue of at least two supporting arms. The transmitting unit comprises a first insulation layer, a non metal conductive layer, a first medium layer and a first surface conductive layer which are superposed from the bottom to the top; and the probing unit comprises a second insulation layer, a metal conductive layer, an isolation layer, an infrared sensitive layer and a photonic crystal microstructure layer which are superposed from the bottom to the top. The integrated device has the advantages of simple structure, stable high temperature properties and adjustable wavelength, and narrow-band absorption probing narrower than the width of wavelength spectrum of the transmitting unit can be obtained. The integrated device of the invention can be applied to infrared gas sensor and infrared spectrometer.

The invention relates to a method for allowing a ground wave over-the-horizon radar to achieve multifrequency transmission and reception simultaneously. Expansion of the ground wave over-the-horizon radar from a single-frequency mode to a multifrequency mode is achieved based on an interframe phase linear offset method. At a transmission end, proper phase offset is set according to a sweep frequency period and frequency ways, a frequency synthesis circuit generates a plurality of transmission signals with different frequencies and interframe phase change rates, and the plurality of transmission signals are transmitted through antennas. At a receiver end, a frequency mixing circuit transduces a plurality of reception signals with different frequencies onto the same frequency, echo signals with multiple frequencies are separated on a Doppler after being subjected to twice fast Fourier transform, and therefore, working in multiple frequencies can be achieved. By means of the method, the ground wave over-the-horizon radar can work in multiple frequencies simultaneously, hardware cost is not added, mutual interference caused by working in multiple frequencies simultaneously is avoided, data obtained in different frequencies can be separated easily, and detection performance and detection accuracy of the radar are improved.

The invention provides a transmission imaging device and method based on a tera-hertz quantum device. The transmission imaging device comprises a light source part, an optical path part and a detection part, wherein the light source part comprises a driving power supply, a first cold head, a first heat sink arranged in the first cold head, a tera-hertz quantum cascaded laser arranged on the first heat sink and a first polyethylene window arranged on the first cold head; the optical path part comprises a first off-axis parabolic mirror, a second off-axis parabolic mirror, a two-dimensional electric translation platform, a third off-axis parabolic mirror and a fourth off-axis parabolic mirror; and the detection part comprises a second cold head, a second polyethylene window arranged on the second cold head, a second heat sink arranged in the second cold head, a tera-hertz quantum trap detector arranged on the second head sink, a signal processing circuit, an oscilloscope and a computer. The device and the method have the advantages that: an adopted tera-hertz radiation source can work in the pulse mode; and due to the adoption of the tera-hertz quantum trap detector serving as a signal detector, the imaging speed of a system can be increased effectively, and the imaging quality can be enhanced.

The invention relates to a random-covariance-matrix-based multi-highlight target time space detection method. A detection problem is solved by using a two-step likelihood-ratio test criterion, thereby realizing detection of a multi-highlight target echo. The method comprises: a group of echo data are obtained by an echo wave received by a sonar array and the obtained group of echo data are used as to-be-detected data; if the reverberation covariance matrix and object guiding vector are known, maximum likelihood estimation values of a target reflection coefficient, an interference index, and a target index are substituted into a likelihood ratio function to obtain a first examination statistical magnitude; and according to inverse-obedience inverse wishart distribution of the reverberation covariance matrix, a maximum posteriori estimation value of the matrix is obtained and thus a second examination statistical magnitude is obtained, and comparison with a threshed value is carried out to complete judgement of target existence. According to the invention, with fully utilization of the priori knowledge, robustness of the high-resolution sonar system is guaranteed under the circumstances that no auxiliary data exit and the inhibition capability of the side-lobe interference is also guaranteed.

The invention discloses an electromagnetic ultrasonic flaw detecting method for eliminating an electromagnetic ultrasonic Lamb wave multi-mode influence, relates to the technical field of ultrasonic detection, and solves the problem that echo signals are complex and cannot be detected caused by the multi-mode characteristic of electromagnetic ultrasonic Lamb waves in the process of realizing non-contact ultrasonic nondestructive detection by adopting the electromagnetic ultrasonic detection method at present. The method comprises the following steps: determining the distance fluctuation range of coil windings of an electromagnetic ultrasonic transducer and a bandwidth range of excitation current frequency introduced in the coil windings according to the property and the thickness of the material of a piece to be detected, so that a probe of the electromagnetic ultrasonic transducer excites single-mode electromagnetic ultrasonic Lamb waves or excites multi-mode electromagnetic ultrasonic Lamb waves with the same propagation speed in the piece to be tested; and starting detecting, acquiring a detection result signal and processing data so as to obtain the position and the size of a flaw in the piece to be detected. The method provides a foundation for the wide application of electromagnetic ultrasonic detection.

The invention discloses a method for generating a Multiple Input Multiple Output (MIMO)-over the horizon (OTH) radar waveform, belongs to the technical field of radar communication and particularly relates to a method for emitting the waveform by generating an MIMO-OTH radar system based on a best emitting signal energy spectrum (ESD). The MIMO-OTH radar is under the noise and the clutter background relied by signals, an ionized layer limits the MIMO-OTH radar working band, the total emission energy is limited, a maximum J separating size serves as a standard, the optimized waveform is generated, the energy spectral density of the orthogonal transmit waveform can be obtained quickly and efficiently through a Maximum marginal income distribution (MMA) algorithm, and the wave sequence of MIMO-OTH radar system emitting signals can be obtained. The generated operation is low in complexity, and emitting signals are high in detection performance of targets.

The invention discloses a high density electrical measurement device and its method to measure polarizability through the use of metal electrodes. The measurement device comprises an electrical instrument and a high voltage direct current power supply device wherein the latter includes a main controller, an isolation driving circuit and an H bridge circuit and the former includes a metal electrode A, a metal electrode B, a metal electrode M and a metal electrode N. Through the cooperation of a high-voltage direct current power supply device and an electrical instrument and rather than the use of a non-polarized electrode to measure the polarizability, the measurement device and the method are easy to operate; compared with the traditional polarization excitation method, the device and method can accomplish higher detection efficiency. Compared with the prior art using polarized electrodes to measure the polarizability, the error of the polarization effect caused by the power supply electrodes to the geology is eliminated, and higher accuracy and detection effect can be accomplished. The device and method are suitable for the exploration of earth resistivity and polarizability.

The invention relates to a deep ultraviolet APD detection diode based on Ir2O3/Ga2O3 and a manufacturing method thereof. The method comprises the following steps of selecting a beta-Ga2O3 substrate; growing a beta-Ga2O3 material on a beta-Ga2O3 substrate surface to form a homogeneous epitaxial layer; growing an Ir2O3 material on a homogeneous epitaxial layer surface so as to form a heterogeneous epitaxial layer; etching the heterogeneous epitaxial layer and the homogeneous epitaxial layer to form a trapezoidal structure; forming a top electrode on a heterogeneous epitaxial layer surface; and forming a bottom electrode on a lower surface of the beta-Ga2O3 substrate and finally forming an APD detector diode. In the invention, the beta-Ga2O3 material is used, a super high light penetration rate and transparency of the material in a deep ultraviolet area and a visible light area are performed, super high voltage withstanding performance of an APD detector and a high breakdown electric field are ensured; the diode is suitable for extreme environments of a high frequency, high radiation, high temperature and high voltage and the like; under the extreme environments, device reliability can be greatly increased and detection performance is better than that of an existing APD detector.

The invention provides a rapid pollution incident detection method based on a traditional online monitor, and belongs to the technical field of environmental engineering water treatment. The method includes the steps: building a pollution-free background database and a polluted background database; building composite sequences, presetting model parameters and optimizing training to obtain optimal parameters; building optimized pollution incident detection recognition matrixes, and recognizing pollution incidents in real time. The pollution incidents can be determined in a short time by the aid of traditional online monitors universally mounted at current monitoring points when abrupt pollution incidents happen, misinformation of the pollution incidents caused by instrument noise fluctuation is effectively avoided, online monitoring cost of the pollution incidents can be greatly reduced as compared with emerging online monitoring technology, all pollutants possibly causing the pollution incidents are covered, and safety and reliability of a water system are furthest guaranteed.

The invention discloses an image receiving and transmitting device integrated with a transparent organic light emitting diode (OLED) micro-display. The image receiving and transmitting device integrated with the transparent OLED micro-display comprises a base plate, a photodiode which is arranged on the base plate and used for sensing light and the transparent OLED which is arranged on the base plate and used for illuminating. An illuminating spectrum of the OLED is not overlapped with a sensitive spectrum of the photodiode. And the image receiving and transmitting device further comprises a light retaining layer which is arranged for the photodiode and only permeable for light which is pre-set and belongs to a wave band sensed by the photodiode. The invention further provides a manufacture method of the image receiving and transmitting device integrated with the transparent OLED micro-display. The light retaining layer is arranged, so that image transmitting and outside light can be blocked under the retaining effect of the retaining layer and image receiving is not affected.

The invention provides a resource configuration method, an information sending method, a base station and a terminal. The resource configuration method is applied to a first base station to which a first cell belongs and comprises the steps of: acquiring configuration parameter information for optimizing the configuration of a physical random access channel resource of the first cell, wherein theconfiguration parameter information comprises resource configuration information about a MulteFire short physical random access channel (MF-sPRACH) of an adjacent cell of the first cell and/or randomaccess channel (RACH) information about the first cell; and configuring the physical random access channel resource of the first cell according to the configuration parameter information. The resourceconfiguration method, the information sending method, the base station and the terminal improve the preamble detection performance of the cell, and improve the success probability of cell random access.

The invention discloses a method for positioning and detecting low-density concealed ore bodies in a gallery gravity total spatial domain. The method includes the steps that firstly, field gallery gravity and gravity gradient observation is conducted, various corrections are conducted on observation data and include the earth tide correction, the null shift correction, the terrain correction, Bouguer correction, latitude correction, gallery correction, gob correction, backfilling zone correction and the like; secondly, concealed ore body positioning detection is conducted according to the gravity anomaly and the gravity gradient anomaly in the X direction, the Y direction and the Z direction, wherein the gravity anomaly and the gravity gradient anomaly are obtained after correction is conducted. The method solves the problems that metal ore bodies are difficult to position in the total spatial domain, and according to other object detection methods, the deep ore bodies are difficult to position and detect accurately due to the influences of electromagnetic interference and anomaly multiple solutions.

The invention relates to a nitrogen oxide donor-quantum dots compound and a preparation method thereof. The preparation method comprises the following steps that: chitosan or chitosan derivative with certain deacelation degree is dissolved in the water, metal salt solution and chalcogenide solution with appropriate quantity are sequentially added into the chitosan or the chitosan derivative solution under a room-temperature stirring condition, a compound of chitosan or the chitosan derivative and quantum dots is obtained by heating and backflowing, dialyzing, evaporating and drying the mixture solution, and then the compound is reacted with nitrogen oxide under a pressurizing condition to prepare a nitrogen oxide donor. Compared with the prior art, chitosan is adopted as a carrier for releasing the nitrogen oxide, quantum dots are adopted as a fluorescent probe for detecting the release of the nitrogen oxide, the nitrogen oxide can be stably released under the phycological environment, a function on detecting the release of the nitrogen oxide can be realized, the biocompatibility is good, no physiological toxicity exists, and a promising prospect can be realized on the diagnosis and treatment aspects of hypertension, heat diseases, respiratory diseases, sexual disorder and the like.

The invention relates to the field of electromagnetic touch and discloses an electromagnetic touch receiving device and an electromagnetic touch receiving method. An annular antenna is coupled to receive an electromagnetic signal sent by an electromagnetic pen so as to obtain an analog receiving signal; the analog receiving signal is filtered to be converted into a digital signal, and frequency and energy of the digital signal are estimated to enable the electromagnetic touch receiving device to adopt an advanced digital signal processing method for precisely calculating energy and frequency information relevant to a touch signal, and anti-interference and receiving performances of the electromagnetic touch receiving device are improved.

The invention relates to a daytime celestial body detecting device, which is characterized by mainly comprising a light shield, a symmetrical turn-back type optical system, an eight-shift light filterturntable, a linear polaroid turntable, a CCD camera and a corresponding mechanical structure. The daytime celestial body detecting device adopts a spectral filtering method and a polarization methodto detect target celestial bodies under a daytime cloudless sky background while having novelties, and improves the performance of detecting the daytime celestial bodies.

The invention discloses a marine radar detection system and a detection method thereof. The system comprises a radar antenna, a radar receiver, a radar transmitter and an ARPA (Advanced Research Projects Agency) radar terminal. The radar transmitter receives a control instruction and outputs state detection data; the radar receiver receives the control instruction and outputs the state detection data; and the ARPA radar terminal is provided with self-adaptive detection processing and control software and transmits a working state setting instruction to a filter for single detection and target track processing in the radar transmitter, the radar receiver and the ARPA radar terminal. The method comprises the steps of land and shoreline detection, echo character parameter calculation, the detection and tracking interaction of a correlative filter, target quality parameter evaluation and radar self-adaptive control. Aiming at a target with different characteristics, the invention acquires the integrated optimization of the detection performance and the resolution performance as well as the detection performance and the tracking performance and forms a self-adaptive marine radar detection system facing to the target.