1104 results about "Ultrahigh frequency" patented technology

A radio frequency (RF) device includes an RF transceiver, an RF antenna, and a magnetic signal detector. The RF is selected to be in the very high frequency (VHF), ultrahigh frequency (UHF), or super high frequency (SHF) bands such that the shielding effect is reduced and the RF device can be configured as a SIM card disposed inside a cellular phone with an increased RF communication range. The magnetic signal detector is used to sense a magnetic field signal from an RF reader, which includes an RF transceiver, an RF antenna, and a magnetic signal transmitter. The longer communication range afforded by the VHF, UHF, or SHF bands is reduced by the sensing of the magnetic field, thereby providing a communication range control, while the RF device and the RF reader exchange information through the RF channel with improved security as a result of the range control.

Tools and methods are provided for dissecting and/or removing biological units, such as hair follicles, from the body surface based on the images both above and below a body surface to reduce potential damage to the removed biological unit. The invention may be used in fully automated systems and also in a hand-held devices and systems. A system may produce a series of three-dimensional images of the body surface indicating follicular unit size, shape, position, and orientation both above and below the skin surface. The images may be utilized by an automated follicular unit harvesting tool, or maybe stored for later use. Imaging techniques include devices that sense light in the visible or infrared spectrums, optical coherence tomography, and ultrahigh frequency ultrasound.

The invention discloses a partial discharging experiment device of a structure-variable combined electrical gas-insulated apparatus and a method thereof, and belongs to the technical field of insulation online detection of electrical equipment. The partial discharging experiment device mainly comprises a GIS simulating element, a digital storage oscillograph and a signal generator, etc. By utilizing the device, the partial discharging experiment method carries out a pressurized experiment so as to collect ultrahigh frequency PD signals, carries out a signal injecting experiment, collects and corrects the ultrahigh frequency PD signals through programs, thus obtaining real waveform of the ultrahigh frequency PD signals. The device can simulate the T-shaped, L-shaped and bar-shaped structures of real GIS equipment. The method can carry out the experiment to the T-shaped, L-shaped or bar-shaped GIS structures by one to four insulated defect models, and the experiment is real, accurate and wide in range. The device and the method can be widely applied to the experimental research of the insulated state online monitoring of GIS equipments in teaching practices, scientific research institutions and equipment manufacturing plants, and the detected PD signals can be used for theoretical analysis and applied research.

The invention relates to a system for calibrating receiving performance of a partial-discharge ultrahigh frequency detection device, and the system comprises a giagahertz transverse electromagnetic cell (GTEM) transmission cell, a standard pulse generator, a measure and control computer and a high-speed broadband oscillator, which are sequentially connected with one another through a conducting wire, wherein the high-speed broadband oscillator transmits a branch signal to the GTEM transmission cell, the top of the GTEM transmission cell is provided with a special test window which is provided with a reference sensor and a tested sensor, and the reference sensor and the tested sensor are respectively connected with the high-speed broadband oscillator. The invention also relates to a calibration method by adopting the system. The calibration system and the calibration method have a broadband property and low cost, and not only can be used for electromagnetic radiation sensitivity test, but also can be used for the electromagnetic radiation test; and moreover, the instruments used in the system and the method are simple to configure, low in cost and capable of being used for rapid and automatic test.

The invention relates to a local discharge detecting system of a sulfur hexafluoride gas-insulating and fully-enclosed combined electric apparatus. A central control unit thereof is connected with anultrahigh frequency signal receiver and an ultrasonic receiver; if the ultrahigh frequency signal and the ultrasonic wave are measured to have continuous correlation, the position of the ultrasonic receiver on the outer wall of a gas insulating switch device is moved for a plurality of times, a time difference of maximum amplitude occurring in an amplitude characteristic print of the ultrahigh frequency signal and maximum amplitude occurring in an amplitude characteristic print of the ultrasonic wave on all the detecting positions is recorded so as to calculate the distance of a discharge point and all the detecting positions; and then the position of insulation defect in the gas insulating switch device is calculated according to the overall size of the insulating switch device.

The invention relates to a multi-region detection system for the partial discharge decomposition components of insulating gas and a method thereof, which belong to the technical field of on-line gas-insulated equipment insulation monitoring. The system comprises a voltage regulator, an isolation transformer, a corona-free test transformer, a partial discharge-free protective resistor, a capacitive divider, an insulating gas discharge decomposition device, an ultrahigh-frequency antenna, an oscillograph, a gas chromatograph-mass spectrometer and the like, and the insulating gas discharge decomposition device comprises a housing, insulating sleeves, connecting rods, electrodes, valves, a vacuum meter, a gas pressure meter, a vacuum pump, an SF6 gas bottle, a pure compressed air bottle and the like. The method utilizes the system to respectively detect the discharge decomposition components of multiple regions in the insulating gas discharge decomposition device. The invention can accurately detect the components and component contents of the decomposed gas of a main gas chamber, a glow discharge region and an electron drift region and provide a standard. The invention can be widely applied to the on-line monitoring of gas-insulated equipment insulation, in particular to the on-line monitoring of GIS (gas-insulated switchgear) insulation.

The invention discloses a partial discharge simulation experiment device of suspended metal particles in oil of a transformer, which belongs to the technical field of partial discharge online monitoring of oil immersed transformers. The partial discharge simulation experiment device mainly comprises an induction regulator, a non-corona test transformer, a non-partial discharge protective resistor, a standard capacity voltage divider, a partial discharge generation device, a noninductive detection resistor, an ultrahigh frequency antenna, a coaxial cable, a broadband high-speed large-capacity digital storage oscillometer and the like. The partial discharge simulation experiment device can simulate stable partial discharge signals generated by the suspended metal particles in flowing oil with different oil flowing speeds at different temperatures when the oil immersed transformer is in a working stage. Therefore, the partial discharge simulation experiment device can be widely applied to the simulation of partial discharge generated by the defect of the suspended metal particles in the oil immersed transformer in a laboratory and can provide reliable experimental data for teaching, scientific research institutions and schools and transformer manufacturers to monitor oil immersed transformers on line and analyze and apply partial discharge signals.

The invention relates to a control method and a system for intersection signal timing guaranteeing the priority of buses. The system adopts an ultrahigh frequency RFID (Radio Frequency Identification) technique to achieve the remote recognition, acquisition and control of information of an onboard unit; and adjusting an intersection signal timing scheme through an optimization algorithm by collecting the information of buses in all direction of an intersection, so as to provide control of passing priority for buses. The control method solves the bus priority mode on common urban roads, and realizes the bus passing priority on the basis of maximizing the overall operation efficiency of vehicles at the intersection, so as to improve the operation efficiency of buses. In addition, the control method is low in cost and convenient to implement and becomes effective fast, and achieves the win-win of the bus priority and the overall operation efficiency of the intersection, so as to reduce delays of buses at urban intersections and ensure the punctuality of buses.

The invention relates to a global information system (GIS) partial discharge on-line monitoring calibration instrument and a configuration authentication method thereof. The calibration instrument is provided with a pulse signal source and a transmitting antenna. When the pulse signal source replacing a high-voltage conductor spike model injects signals of a simulation partial discharge source through an external sensor as the transmitting antenna into a GIS cavity, the calibration instrument carries out checking on sensitivity of a partial discharge ultra high frequency (UHF) detecting device in the process that the partial discharge UHF detecting device detects the signals on line on the basis of an ultrahigh frequency method. The configuration authentication method includes the steps of testing time domain waveform and spectrum characteristics of a UHF signal model radiated by a typical discharge source inside a GIS, providing technical parameters of the pulse signal source, injecting the pulse signals into the high-voltage conductor spike model on an entity GIS platform, injecting pulse signals into the GIS cavity through an internal sensor and the external sensor, and then carrying out equivalent checking.

The invention discloses a gas insulated substation (GIS) partial discharge online monitoring system and a fault mode identifying method thereof. The monitoring system comprises an ultrahigh frequency sensor, a signal preprocessing subsystem and a data processing subsystem, wherein the data processing subsystem comprises a monitoring and spectrogram display module, an off-limit alarm module and a mode identifying module; and a partial discharge signal acquired by the ultrahigh frequency sensor is transmitted into the data processing subsystem after being processed by the signal preprocessing subsystem so as to realize the monitoring and spectrum display of the partial discharge and the functions of off-limit alarm and fault mode identification. The system and the method have the beneficial effects that by adopting the GIS partial discharge online monitoring system and the fault mode identifying method thereof, the long-term online monitoring function on the partial discharge of the GIS is realized, and meanwhile, the fault type of the partial discharge can be identified well by utilizing the mode that a neural network identifying method based on a fuzzy rough set.

The invention belongs to the field of on-line monitoring technology of insulative condition of SF6 (sulfur hexafluoride) gas insulated electric equipment, and in particular relates to a gas insulated electric equipment partial discharge multi-source joint detection method. The detection method mainly comprises the steps of preparing a test, cleaning a stainless steel cylinder, filling with SF6 gas, performing an industrial frequency AC SF6 gas PD test, pulse current detection, ultrahigh frequency sensor detection, fluorescent optical fiber sensor detection, discharge gas collection and component detection and the like. The detection method provided by the invention is simple in operation, liable to promote, and provides references for multi-dimensional information joint detection method. The detection method is widely applied to SF6 gas insulated electric equipment partial discharge multi-sensor joint detection under the condition of power frequency, and provides a simple test scheme for multi-dimensional information extraction of PD (Potential Difference) decomposition characteristics and a decomposition theory.

The invention discloses a localizable ultrahigh-frequency cable partial discharge detection method and device. The invention is characterized in that a data synchronous acquisition module comprises two high-speed acquisition channels and one low-speed acquisition channel, two ultrahigh-frequency sensors and one power-frequency signal sensor are externally connected for synchronous acquisition of ultrahigh-frequency partial discharge signals, environment signals and power-frequency voltage signals below 1GHz, and the ultrahigh-frequency sensors are directly arranged on a cable; an analyzing and processing module compressively analyzes the acquired synchronous data by the five combined method, effectively identifies cable partial discharge signals and external noise interference and further realizes partial discharge positioning; a power denoising module is used to prevent introduction of noise interference by a portable power source during outdoor use; and a user control terminal has the functions of data acquisition display, result analysis, historical data review and real-time report printing. The invention makes it possible to detect and position partial discharge of power cables, improves the reliability of partial discharge detection and realizes accurate judgment on partial discharge.

The invention provides a dairy farm wireless monitoring system based on the internet of things. The dairy farm wireless monitoring system based on the internet of things comprises a passive RFID module, an ultrahigh-frequency RFID read-write device, a non-contact type infrared temperature measuring module, an environmental information sensing module, a plurality of wireless communication nodes, a gateway module, a coordinator module, a remote server and a user terminal. The dairy farm wireless monitoring system based on the internet of things is based on application of integration between a sensor for the internet of things and a Zigbee wireless communication technology, the problems that according to a traditional management mode, power consumption is high, the delay time is long, management lags behind and safety cannot be ensured are solved, a traditional dairy cow mode is changed into an accurate management mode using an information network as the center, and animal husbandry production can be automated, networked and intelligent; the dairy farm wireless monitoring system based on the internet of things is intelligent, low in cost, easy to extend and manage, simple and convenient to use.

The invention belongs to the field of signal processing, relating to a phase-based indoor positioning algorithm, especially to a phase-type distance measuring method for ultrahigh frequency RFID positioning. The method comprises that a single-frequency subcarrier amplitude modulation manner is carried out on selected ultrahigh carrier frequency and subcarrier frequency; it is presumed that emission signals are propagated in a line-of-sight manner; phases are extracted via a discrete frequency spectrum correction technology; a formula for calculating a phase difference of subcarrier signals at transmitting and receiving ends is obtained; distances between readers and a label are calculated; and in the whole positioning system, distances to the same label are respectively measured via the multiple readers, and under the condition that the distances from the readers to the to-be-measured label are known, the label is positioned via a dual-curve least square positioning algorithm. According to the phase-type distance measuring method for ultrahigh frequency RFID positioning, precision in positioning a moving object in a complex environment can be improved.

The invention provides a method and system for recognition of a GIS ultrahigh frequency partial discharge signal. The method for recognition of the GIS ultrahigh frequency partial discharge signal comprises the following steps of (1) carrying out preprocessing on the GIS ultrahigh frequency partial discharge signal to obtain a three-dimensional spectrogram, (2) carrying out projection on the three-dimensional spectrogram to form a two-dimensional spectrogram, respectively extracting discharge characteristic parameters which describe shape difference of the two-dimensional spectrogram, and discharge characteristic parameters which describe difference between a positive semi-circle outline and a negative semi-circle outline of the two-dimensional spectrogram to obtain a sample to be detected, and (3) carrying out defect recognition on the sample to be detected according to an ABC-BP model which is built in advance. The method for recognition of the GIS ultrahigh frequency partial discharge signal can carry out rapid convergence to obtain the global optimum, and improves efficiency and accuracy of fault recognition of GIS partial discharge.

The invention relates to a portable cable local discharge detection device in the technical field of electric power detection. The portable cable local discharge detection device comprises a sensor, a detection terminal and a control module, wherein the input end of the sensor is connected with an electric cable for detection, the output end of the sensor is connected with the detection terminal for transmitting an analog sensing signal, and the control module is connected with the detection terminal for receiving the analog sensing signal and outputting a control instruction and a detection result. The invention has compact structure, convenient mobile detection because a box body is provided with a wheel structure, high working efficiency, higher sensitivity and signal to noise ratio, and can be applied to effectively detecting local discharge of a cross linked polyethylene (XLPE) cable on site by comprehensively applying four detection methods of a high-frequency current method, an ultrahigh frequency method, an ultrasonic method and an infrared temperature method.

The invention discloses an ultrahigh-frequency wireless sensing tag which combines the passive operating mode with the semi-active operating mode. The ultrahigh-frequency wireless sensing tag comprises a radio frequency rectifying circuit, an ASK signal demodulation circuit and a back reflection modulator circuit which can change the input impedance of an antenna, in this way, wireless receiving and transmitting of sensing data can be achieved through the tag in a passive mode, and power consumption and cost are reduced. When the passive operating mode of the tag is started, an on-chip sensor can be started for acquisition and transmission of the sensing data; when the semi-active operating mode of the tag is started, an off-chip sensor can be started for acquisition and transmission of the sensing data. According to the sensing tag, a command specified in ultrahigh-frequency RFID international standard ISO 18000-6C and EPC C1G2 is used for starting of the on-chip sensor or the off-chip sensor and controlling and uploading of the data, in this way, a special control chip does not need to be designed, and any ultrahigh-frequency reader-writers according with the international standard can be used for acquiring and uploading the sensing data.

The invention discloses a portable partial discharge detecting and diagnosing device. The device comprises a partial discharge detector, a cable, a pre-sensor and a charger device, wherein the partial discharge detector comprises a lower computer and an upper computer; the lower computer comprises a simulation unit module, an FPGA module, an ARM module, a clock and reset module and a power management module; the upper computer is a Linux industrial personal computer. The portable partial discharge detecting and diagnosing device is provided with a 14-bit 100MHz two-channel acquisition system having the maximum storage depth of 64Mbit; the display of the characteristic spectrum of defects and the model identification of faults can be completed accurately in such a manner of PRPD clustering analysis in combination with impulse waveform time-frequency analysis; meanwhile, a radio-frequency sensor and an ultrahigh-frequency sensor are simultaneously provided, and the pulse current detection and the ultrahigh-frequency detection on primary equipment can be completed by replacing the pre-filter; the device is small in volume, light in weight, and capable of supplying power to a battery and convenient for field live testing and polling of a transformer.

The invention discloses a high-voltage power cable fault recognition method, and the method comprises three processes: signal combining collection, signal comprehensive processing, and fault intelligent recognition. The process of signal combining collection comprises the steps: collecting electromagnetic transient states and electromagnetic waves through employing a UHF ultrahigh frequency sensor, collecting supersonic signals through employing a piezoelectric-type AE supersonic sensor, collecting ground waves through employing a TEV ground wave sensor, and collecting a transient magnetic field through employing an HFCT high-frequency current sensor. The process of signal comprehensive processing comprises the steps: extracting a plurality of statistical feature parameters representing discharging intensity from partial discharge broadband time domain data, extracting various types of feature parameters of partial discharge caused by a cable fault, and constructing a partial discharge fingerprint feature library corresponding to various types of defects. The process of fault intelligent recognition comprises the steps: enabling the extracted time domain feature parameters to be inputted into two types of intelligent recognition algorithms in batches for automatic matching and recognition, carrying out constant comparison and gathering of the recognition results of the two algorithms, and determining the type and size of the fault. The method is safe in detection, is quick and accurate in fault recognition, and can be integrated.

The invention relates to an intelligent self-service shopping system and method for a supermarket. The system comprises an ultrahigh-frequency RFID reading-writing device, an ultrahigh-frequency RFID tag, a two-dimensional code, a smart phone, and a background server. The RFID tag and the two-dimensional code are pasted on the surface of a commodity simultaneously. In addition, the self-service shopping method using the system includes: a customer uses an application program installed at the smart phone for scanning two-dimensional codes installed at the surface of commodities, obtains the commodity information from the server, carries out selective purchasing, and then uses the smart phone for self-service payment for purchasing. When the customer passes the exit of the supermarket with the commodities, the RFID reading-writing device and the server that are arranged at the exit check whether the commodities have been paid simultaneously and a commodity list is displayed at a display device integrated with the reading-writing device simultaneously. If all the commodities have been paid, the customer is allowed to pass the exit; and otherwise, alarming is carried out. Therefore, the shopping efficiency of the customer can be improved; time for searching for commodities and queuing up for payment is saved; no professional shopping terminal is needed; and thus the manpower and materials are saved for the supermarket.

The invention discloses a GIS fault detection system and a GIS fault detection method based on multi-source information fusion and a deep learning network. The GIS fault detection system comprises a multi-source information acquisition and conditioning module, a deep learning module and an information fusion and fault reasoning module, wherein the multi-source information acquisition and conditioning module performs fault state monitoring on a GIS system by adopting a partial discharge time analysis method, a partial discharge phase analysis method and an ultrahigh frequency method separately, extracts corresponding feature vectors separately from obtained current, voltage and electromagnetic information and outputs the feature vectors to the deep learning module; the deep learning module performs online pattern recognition on the three kinds of feature vectors based on the deep learning network obtained through offline learning optimization to acquire corresponding recognition results, and outputs the recognition conclusions to the information fusion and fault reasoning module; and the information fusion and fault reasoning module carries out fusion processing on the three recognition conclusions to obtain a fault feature matrix, and then obtains a fault conclusion by means of a CLIPS reasoning machine. By adopting the GIS fault detection system and the GIS fault detection method, the fault information of the GIS system can be diagnosed quickly, efficiently and precisely.

The invention discloses an L-shaped ultrasonic array sensor for partial discharge location of a transformer. The ultrasonic array sensors are arranged in an L-shaped manner at equal intervals; the number of array elements (piezoelectric sensors) is 3-300; and an ultrahigh-frequency sensor is located on a right-angle inner side formed by the L-shaped ultrasonic array, shielded by metal around and provided with a matching layer on the bottom surface. The L-shaped array is subjected to virtual expansion by use of higher order cumulant technology; the expanded virtual array is subjected to direction estimation by a spatial spectrum estimation algorithm, then wave beam synthesis is performed on the estimated direction; and with assist of the electric impulse or ultrahigh-frequency electromagnetic wave signal generated by the partial discharge, the propagation delay of ultrasonic wave in transformer can be obtained so as to perform location. The follow-up hardware circuits of the sensor can be greatly reduced, and the manufacturing cost is saved; and moreover, the Gaussian color noise can be effectively inhibited, being beneficial to the practical use of array technology in the field of partial discharge detection.

A radio frequency identification reader and a radio frequency identification tag that use an ultrahigh frequency band, and action methods of the radio frequency identification reader and the radio frequency identification tag. The radio frequency identification reader includes: a data generator generating data to be transmitted to a radio frequency identification tag; if a command to control the radio frequency identification tag has to be authenticated, a reader controller controlling the data generator to generate the data including an authentication code; and a reader transmitter transmitting the data to the radio frequency identification tag. As a result, securing of communications of a specific command between the radio frequency identification reader and the radio frequency identification tag can be reinforced.

The invention discloses a partial discharge pattern recognition method based on a mixed neural network algorithm, the method comprises a judge process including extracting ultrahigh frequency partial discharge signal characteristic and establishing a value set library and discharge types; the method specifically comprises: establishing a typical partial discharge model firstly, acquiring a discharging ultrahigh frequency signal, and performing mixing frequency and reducing frequency process; then generating 5 kinds of two-dimension spectra according to the discharge signal, and extracting 37 kinds of statistical characteristic quantity (value set) to form the value set library; finally comparing the value set library and a value set corresponding to the statistical characteristic quantity calculated by a fault signal through the mixed neural network algorithm, and recognizing the partial discharge type of a transformer. According to the invention, the signal of partial discharge ultra wide band is fully ultilized, the single neural network pattern recognition problem is overcome, the partial discharge value set library of the transformer is established to perform pattern recognition for different kinds of discharging, the valuable data is provided for transformer partial discharge on-line monitor, and the method has good practical engineering value.

Provided herein is a cancer detection and treatment instrument comprising: a first conductive plate; a second conductive plate which is opposed to the first conductive plate and has a first opening; a first signal line disposed between the first conductive plate and the second conductive plate; a first contact member of which one end is exposed through the first opening and of which the other end is connected to the first signal line; a dielectric portion filled between the first and second conductive plates and the first signal line; and a conductive layer surrounding both side surfaces and a front end surface of the dielectric portion which are exposed. Therefore, it is possible to accurately detect cancer by the use of the ultrahigh-frequency signal and to treat a diseased portion without damaging tissues around the diseased portion.

The invention discloses an XLPE cable partial discharge defect type identification method. The method comprises the following steps: obtaining the de-noised XLPE cable ultrahigh frequency PRPS graph; extracting and computing four dimension statistical characteristic parameters and six non-dimension characteristic parameters of the PRPS graph; inputting the characteristic parameters to SOM neural network model; determining the win nerve cell, continuously learning through updating the weight vector of the win nerve cell by the SOM neural network, until the input sample corresponding to the output layer win nerve cell is stable; and outputting the type identification result of the SOM neural network. The XLPE cable partial discharge defect type identification method is capable of overcoming the defects of the traditional method that the convergence speed is slow and the judgment accuracy is bad, satisfying the visual requirement of the fault analysis, and improving the intelligent level of the XLPE cable partial discharge detection system, has the characters of rapid detection speed, simple process and high diagnosis accuracy, and is good for accurately evaluating the running state of the XLPE cable by the maintenance worker.

The invention belongs to the electric power equipment fault detection and diagnosis technology field and especially relates to an XLPE power-cable partial discharge diagnosis method and a system thereof. The method comprises the following steps of collecting a low-frequency ultrasonic wave signal and an ultrahigh-frequency partial discharge signal generated by power-cable partial discharge, acquiring time delay of the ultrasonic wave signal and acquiring a distance between a partial discharge point and a partial discharge detection point; determining a phase window which has partial discharge; establishing a relation between an ultrasonic wave signal amplitude of the phase window and a phase of an applied power frequency voltage; drawing ultrasonic partial discharge phase information and amplitude information into a phase spectrum graph; and carrying out statistics characteristic calculating and extracting 27 statistics operators representing a partial discharge characteristic. In the invention, the ultrahigh-frequency partial discharge signal generated by the partial discharge is taken as a time reference and is combined with a low-frequency ultrasonic partial discharge signal so as to acquire time delay of the ultrasonic signal, and finally identification of the partial discharge signal is realized.

The invention discloses a calibration system and a calibration method of a partial discharge ultrahigh frequency detection device in the technical field of online detection of the partial discharge of power transformers and gas insulation combination switch devices. The calibration system comprises a standard antenna, a standard pulse source, a detection and control computer and a partial discharge ultrahigh frequency detection device to be detected, wherein the standard pulse source, the detection and control computer and the partial discharge ultrahigh frequency detection device to be detected are connected sequentially. The partial discharge ultrahigh frequency detection device to be detected comprises a sensor for collecting voltage signals. The calibration system further comprises a coaxial cavity, the coaxial cavity is composed of an outer cylinder, an inner cylinder, two outer cones and two inner cones which are coaxial, and a detection window is arranged in the middle of the outer cylinder. The invention also provides the calibration method with the calibration system. The calibration system utilizes the matched coaxial cavity to replace a small GTEM (Giagahertz Transverse Electromagnetic Cell) for the calibration of the partial discharge ultrahigh frequency detection device, and is simple in structure and easy to implement.

An externally arranged ultrahigh frequency partial discharge detection sensor comprises a metal shielding outer shell, a microstrip antenna and a coaxial cable connector. The metal shielding outer shell is a box body with an opening at the bottom, and the lower bottom edge of the long side wall is arc-shaped. The microstrip antenna is arranged in the metal shielding outer shell and is a rectangular paster antenna. Long edges of a conductor paster are respectively provided with an inward concave arc notch, arc notches are symmetrically arranged using a geometric center of the conductor paster as a symcenter, the microstrip antenna is arranged in the metal shielding outer shell through a dielectric substrate, and an earth plate of the microstrip antenna is a metal shielding outer shell. An integrated circuit board is arranged in the metal shielding outer shell. A low noise amplifying circuit connected with the microstrip antenna, a detector circuit, an amplifying circuit which outputs signals through the coaxial cable connector, and a power supply circuit are arranged on the integrated circuit board. The externally arranged ultrahigh frequency partial discharge detection sensor integrates the microstrip antenna, the integrated circuit board and the shielding outer shell, and is high in sensitivity, small in signal distortion, good in signal-to-noise ratio characteristic, and capable of keeping characteristic information of partial discharge signals to the maximum limit.

The invention provides a high-linearity low-noise amplifier of the front end of an ultrahigh-frequency RFID (radio frequency identification) receiver. The amplifier detects two common levels from two differential output ends of a full-differential amplifier through a common-feedback circuit, bias current of the amplifier is adjusted validly and feedback voltage is outputted to a grid of a tail current source, and accordingly, overdrive voltage of the tail current source is increased, input current is increased and linearity is improved. Meanwhile, the problem of non-linear distortion caused by instability of the output common levels is solved. In addition, a coupling capacitor is crossed interstagely to increase power grain, and noise figure is reduced to improve noise performance. The high-linearity low-noise amplifier has the advantages of low noise figure, low power consumption, and high linearity, and solves the problem of carrier leak in ultrahigh-frequency RFID receivers and zero intermediate frequency receivers, and linearity of the low-noise amplifier is improved, so that weak available signals can be amplified linearly and distortionlessly in the process of receiving block signals.