163 results about "Very high frequency" patented technology

The invention belongs to the technical field of power equipment detection, and particularly relates to a multi-source partial discharge positioning method and system for power equipment. The method comprises the following steps: collecting a partial discharge pulse signal through a very high frequency sensor; establishing a three-dimensional simulation model of the power equipment to be tested; performing time reversal operation on the pulse signal, and reversely injecting the signal subjected to time reversal transformation into the three-dimensional simulation model to obtain distribution of an inversion electric field; processing the inversion electric field signal to obtain a windowed phase spectrum; calculating the cross-correlation between the windowed phase spectrums of the inversion electric fields of the pair of sensors to obtain the distribution condition of the cross-correlation of the windowed phase spectrums; and based on the distribution condition of the windowed phase spectrum cross-correlation, determining the position of one or more maximum cross-correlation, and positioning the partial discharge position. According to the time reversal method based on the phase spectrum cross-correlation criterion, multi-source partial discharge positioning is achieved, the method is not prone to being influenced by signal amplitude attenuation, and the specific position of partial discharge in power equipment can be accurately determined.

The invention discloses a broadband lightning very high frequency radiation source positioning method based on an ESPRIT algorithm, and the method comprises the steps: 1, constructing an orthogonal uniform linear very high frequency antenna array, and collecting broadband lightning very high frequency signals; 2, discrete Fourier transform is carried out on the broadband thunder and lightning very-high-frequency signals, the broadband thunder and lightning very-high-frequency signals are divided into J frequency points, and the frequency domain value of each frequency point signal is worked out; step 3, dividing the orthogonal uniform linear very high frequency antenna array into two sub-arrays in an x-axis direction and a y-axis direction, positioning each frequency point value of the signals in the two directions by using an ESPRIT algorithm, and respectively obtaining a calculation incident angle of each frequency point in the two directions; step 4, carrying out phase ambiguity resolution on the calculated incident angles of each frequency point in the two directions so as to obtain a real incident angle; and 5, calculating the azimuth angle and the elevation angle of the radiation source according to the real incident angle. According to the invention, rapid and refined positioning imaging of the lightning radiation source can be realized.

A system for wireless power transfer (WPT) is described. The WPT system may be used for charging of electric vehicles or other mobile platforms. The WPT system includes a gap waveguide base including a conductive waveguiding structure and a bandgap structure along at least the lateral sides of the waveguiding structure. The WPT system also includes a charging plate separate from the gap waveguide base. The charging plate includes a conductive plate having a receiving structure for receiving the electromagnetic field from the gap waveguide base through an air gap. The disclosed WPT system enables propagation of an electromagnetic field through the air gap, including electromagnetic fields in the very high frequency (VHF) band.

The utility model discloses a filter based on very high frequency adjustment, comprising an inner housing and a function module, both sides of the inner housing are provided with installation chutes, the function module is inserted and installed in the installation chutes, the outer side of the inner housing is fixedly provided with a plurality of heat radiation fins in an array, and the outer side of the inner housing is sleeved with an air duct pipe. The function module is fixedly provided with a plurality of heat dissipation blocks, one end of the air duct pipe is fixedly provided with a heat dissipation fan, the side face of the inner shell is provided with an interface window, the interface window penetrates through the heat dissipation fins and the air duct pipe, the interface window is fixedly connected with a sealing cover through bolts, and the end, away from the heat dissipation fan, of the inner shell is fixedly connected with an adjusting end cover. According to the utility model, the radiating fins and the air duct pipes are arranged to form a plurality of ventilation ducts on the outer side of the inner shell, the cooling fan is used for cooling the outer side of the inner shell through flowing air, and airflow does not enter the inner side of the inner shell, so that the influence of dust accumulation on the operation of the functional module is reduced while the cooling is performed.

The invention belongs to the technical field of ultrasonic positioning diagnosis, and discloses an ultrasonic phased array positioning diagnosis method for a dry-type bushing capacitor core with a microcrack defect, and the ultrasonic detection technology is a nondestructive detection method, and cannot damage a detected insulating material, so that the ultrasonic phased array positioning diagnosis method is suitable for long-term monitoring and preventive maintenance. As the ultrasonic wave has very high frequency and energy, the ultrasonic wave can penetrate through a thicker layer of the insulating material, so that tiny defects and changes can be found. The ultrasonic detection technology can find out the defects of aging, bubbles, impurities, cracks and the like in the insulating material, and can also be applied to other types of electrical equipment, such as cables, transformers and the like, so as to evaluate the insulating properties of the electrical equipment. And taking the discharge signal starting time measured by an electric detection method as a reference to obtain time delay data of all the sensors, and then carrying out next positioning calculation.

The invention discloses a method and a device for processing VHF (very high frequency) and UHF (ultra high frequency) navigation signals based on ZYNQ, and relates to the technical field of signal processing, and the method and the device are characterized in that a single ZYNQ chip is used for replacing an FPGA (field programmable gate array) + DSP (digital signal processor) dual-chip framework of a digital processing part of a traditional aviation navigation signal receiver, so that the system integration level is increased, the design is more compact, the circuit design is simpler, and the system reliability is improved. Lightweight design of airborne equipment is facilitated; besides, by means of the strong processing performance of the PL part of the ZYNQ chip and the high-speed analog-to-digital conversion chip (ADC) which develops rapidly, receiving of VHF and UHF navigation signals can be achieved through the radio frequency direct sampling technology, complete digitization of analog down-conversion is achieved, and the advantages are that the problems of leakage and frequency offset of an analog local oscillator and generation of more harmonic waves and stray can be solved. And the electromagnetic interference of equipment is obviously reduced.

The invention relates to a ring main unit intelligent detection and fault early warning method and system. The method comprises the following steps: deploying an ultrahigh frequency sensor, an infrared thermal imager, an ultraviolet sensor and a high-frequency current transformer, and synchronously acquiring multi-modal data such as partial discharge, temperature distribution, corona discharge and grounding current of the ring main unit; carrying out feature extraction on the collected data, wherein the feature extraction comprises a time-frequency statistical feature and a temperature-load correlation feature of the partial discharge signal; the Dempster-Shafer evidence theory is utilized to carry out fusion calculation on the multi-source feature evidence, and confidence coefficients for insulation degradation, poor contact, arc faults and other fault types are obtained; arc fault prediction is carried out in combination with a long-short-term memory network model; and finally executing a grading early warning strategy according to the fault confidence. The problems of low detection reliability and fault early warning lag of a single sensor are solved, early accurate diagnosis and predictive maintenance of the insulation fault of the ring main unit are realized, and the operation safety and reliability of power equipment are remarkably improved.

The invention relates to the technical field of target detection and identification, and discloses a low-altitude target identification system and method combined with multi-band signal processing. Comprising the steps of establishing a cross-frequency implicit vector model and constraining a geometric scale, a scattering center and rotor harmonic waves through synchronous acquisition of an L-band radar, a Ku-band radar and a millimeter-wave radar, and realizing unified characterization of multi-frequency signals; receiving a global satellite navigation system reflection signal, communication channel state information or a very high frequency / ultrahigh frequency passive radar signal to form prior discrimination, and triggering high-frequency radar short-time imaging; carrying out propagation correction on millimeter wave, terahertz and infrared signals in combination with a meteorological profile and generating an environment label; determining a sampling window by using the region of interest and rotor phase prediction, and optimizing a residence strategy; harmonic waves are extracted from radar and acoustic signals, robust pairing is carried out, and a cross-domain consistency score output category is calculated. The method realizes multi-frequency multi-source cooperative processing, has environment self-adaption and closed-loop feedback capabilities, and can improve the precision and stability of low-altitude target identification.

The utility model discloses a performance evaluation system of ultrahigh frequency partial discharge test equipment. The performance evaluation system is composed of an upper computer module, a radio frequency signal emission module, a pulse source acquisition module and a partial discharge tester to be evaluated. In the pulse source acquisition module, a plurality of coils are wound and connected in series to imitate a connection structure in a three-phase stator, and a high-voltage relay short circuit mode is adopted between every two coils to simulate a damage structure between opposite phases, so that the working condition of poor insulation between the opposite phases of the motor stator is simulated; the defect that performance evaluation for the pulse output source in the motor stator phase-to-phase test is lacked in the prior art is overcome, actual use and operation are facilitated, and evaluation requirements of various different devices can be met.

The invention discloses a coal mine substation intelligent operation and maintenance early warning management system based on multi-source information fusion, and belongs to the technical field of coal mine substation operation and maintenance early warning. The multi-source sensing layer comprises an environment sensor arranged in a substation switch cabinet, an ultrahigh frequency partial discharge sensor array embedded in the root part of a switch cabinet insulating sleeve and the periphery of a GIS basin-type insulator, and vibration sensors mounted on a transformer shell and a circuit breaker operating mechanism mounting surface, and the environment sensor is used for detecting humidity and dust concentration; the ultrahigh-frequency partial discharge sensor array is used for capturing ns-level partial discharge pulses in real time and dynamically predicting the growth trend of the insulator surface contamination degree through the partial discharge amount, and the vibration sensor recognizes mechanical looseness through vibration spectrum features. According to the method, the pollution degree is associated with the partial discharge amount, so that early warning is changed from passive fault response to active risk pre-judgment, an accurate triggering condition and a decision basis are provided for operation and maintenance, and a changing curve of the insulator pollution degree along with the environment or the operation time is analyzed through data accumulation.

A helix antenna and methods of making and using helix antenna to concurrently or independently radiate pulses in a very high frequency (VHF) band in a range of about 240 MHz to about 270 MHz and / or in an ultrahigh frequency (UHF) band in a range of about 360 MHz to about 380 MHz which can be useful in space to ground data transmissions, subsurface radar, and measurement of ice and snow pack.

The invention provides an airborne glacier detection radar system and an imaging processing method, and belongs to the technical field of radar information acquisition. The airborne glacier detection radar system consists of a fully polarized antenna unit, a power amplifier unit, a host control unit, a storage unit, an inertial navigation unit, a power supply unit and an upper computer monitoring unit, and is used for transmitting and receiving electromagnetic wave signals through an antenna to carry out perspective detection on a glacier; echo signals of the atmosphere and the glacier surface layer, the glacier internal structure and the glacier bottom layer and bed rock are obtained, and the glacier perspective detection capability is achieved. An airborne glacier detection radar is integrated on an aircraft platform, and one-dimensional section information of a glacier is obtained through airborne motion. Wherein the vertical resolution of the very high frequency airborne glacier detection radar is superior to 2 meters, and the glacier detection depth is superior to 100 meters. According to the invention, a new technical means is provided for the airborne glacier detection system in the application research aspects of polar glacier reserve estimation, ice layer thickness measurement, glacier fine structure and under-ice landform detection and the like.

The invention relates to a high frequency cable coupler. Compact cable couplers connect cables with different wire gauges and do not interfere with electrical performance up to very high frequencies. Each cable coupler has a pair of conductive elements having first and second contact portions on opposite ends that terminate the wires of the first and second cables. A housing surrounds the conductive element, including a cable attachment. The conductive layer extends from the first cable to the second cable and is conformal with the underlying surface. The housing has a region having a lower dielectric constant adjacent the cable attachment. A parameter of the cable coupler in each of the plurality of portions may be selected to provide a matched impedance through the coupler. Such couplers enable dense connection of small diameter cables with connectors while large diameter cables provide low loss routing to remote locations to achieve high density signal connections with high signal integrity at frequencies sufficiently high to support 224 Gbp.

The present invention relates to a simple VHF frequency band channel transceiver, belonging to the technical field of very high frequency transceivers. It is composed of a device box and a circuit board. The device box is composed of a shell, a cover plate and a shielding cavity. The receiving / transmitting channel module installed on the circuit board contains a receiving circuit, a transmitting circuit and a power supply circuit; the receiving circuit is composed of a low-noise amplifier frequency selection, mixing, intermediate frequency amplification, intermediate frequency crystal filtering, automatic gain control, receiving demodulation and receiving frequency synthesis circuit; the transmitting circuit is composed of a transmitting frequency synthesis, a transmitting pre-stage drive amplifier, a transmitting post-stage drive amplifier and a power detection circuit; a plurality of shielding cavities are milled in the shell and the cover plate, and the shielding cavities are respectively equipped with individual module circuits of the receiving circuit and the transmitting circuit, and the shell and the cover plate are sealed and shielded for the circuit board. The integrated design of the transceiver channel machine and the radio frequency carrier 4FSK digital signal modulation are realized. The receiving intermediate frequency, image frequency, intermodulation and spurious response indicators are excellent, the multi-channel operation has no crosstalk, the analog sensitivity is high, the volume is small, the noise is small, the harmonic spurious suppression is high, and the receiving dynamic range is large.

The invention discloses a communication method and device for marine very high frequency equipment, electronic equipment and a storage medium. The method comprises the following steps: determining an original voice signal, performing signal processing on the original voice signal, and determining semantic text data; performing data processing on the semantic text data, and determining effective text data in the semantic text data; generating an effective text signal corresponding to the effective text data, and transmitting the effective text signal to a voice receiving end through a target communication channel; and the voice receiving end determines a target communication voice based on the effective text signal. Based on the technical scheme of the invention, the communication quality of the marine very high frequency equipment can be effectively improved.

The invention discloses a Doppler very high frequency omnidirectional beacon transmission channel closed-loop calibration system and method, and relates to the technical field of calibration optimization, and the method comprises the steps: calling the transmission data of beacon equipment under different environment conditions; constructing a beacon prediction model according to the deep learning model, inputting the emission data in combination with the environment state into the beacon prediction model for training, predicting the change trend of the beacon emission performance, and marking the current environment state; generating an environment state transition matrix according to an environment state marking result in combination with a performance change trend prediction result, and dynamically updating an environment state transition probability; according to the historical emission data, the environmental state transition probability and the phase noise level corresponding to each piece of historical emission data, calculating the influence rate of the environmental change on the beacon emission performance; dynamically adjusting calibration parameters of the beacon transmitting channel according to the calculated influence rate; through a deep learning model and a dynamic calibration mechanism, the problem that the beacon emission performance is influenced by environmental changes is solved.

The invention belongs to the field of overall shape design of airplanes, and relates to a four-element detection antenna array layout configuration on two sides of a fuselage. According to the structure, four-element VHF (very high frequency) interferometer antenna arrays of 30-300 MHz are symmetrically arranged on the two sides of a machine body between 30-31 stringers on the left side and the right side of 11-22 frames; the outer surface of the antenna array is subjected to pneumatic modification design and is in a tongue shape; the antenna array on each side is composed of four trapezoidal antennas which are a first antenna array element, a second antenna array element, a third antenna array element and a fourth antenna array element in sequence from the machine head to the machine tail.

The invention discloses a very high frequency broadband radiation source positioning method based on energy weighted subspace fitting, and relates to the technical field of signal processing and radiation source imaging, and the method comprises the steps: carrying out the DFT processing of a lightning very high frequency broadband signal collected by an array, and obtaining any narrowband component; then characteristic decomposition is carried out on covariance matrixes of X-axis and Y-axis sub-arrays according to array receiving signals, main characteristic vectors are taken as signal sub-spaces, in order to emphasize the signal sub-spaces with higher energy, characteristic values are used for weighting, weighted signal sub-spaces are constructed, then the signal sub-spaces are fitted by using a least square method, and the signal sub-spaces with higher energy are obtained; the method comprises the following steps: further constructing a sub-band energy weighted spatial spectrum adapted to a very high frequency broadband signal, then carrying out spectrum peak search on the weighted spatial spectrum to obtain a spatial angle of a spectrum peak, and finally calculating the direction of arrival of a radiation source according to a spatial angle relation to obtain an azimuth angle and an elevation angle. According to the invention, aiming at a lightning very-high-frequency weak radiation source positioning problem, a lightning channel can be inverted more clearly.

The invention relates to the technical field of block chain data security, in particular to a power data tamper-proofing integrity protection method, system and device based on a block chain and a storage medium. Receiving a multi-source data stream from a power system, and classifying the multi-source data stream according to the sensitivity level and the sampling frequency of the data; representing each data record as a node in a directed acyclic graph, establishing a directed edge carrying a digital signature between the nodes to represent a data reference relationship, and calculating the confirmation degree of the current node through the confirmation degree of the precursor node and the dynamic weight of the edge; adopting Markov chain Monte Carlo sampling to select an evidence storage path with the highest confirmation degree from the candidate paths, and calculating the confidence coefficient of the transaction node based on the quoted historical transaction quantity; and for extremely high frequency data or low sensitive data, the legality of the power transaction is converted into a verification circuit defined by a constraint coefficient, a certification key and a verification key are generated, and the data source equipment generates zero knowledge certification for data meeting constraint conditions by using the certification key.

The invention discloses a digital baseband processing method and device for a very high frequency omnidirectional beacon signal and a receiver, and relates to the technical field of signal processing, and the technical scheme is characterized in that the method comprises the following steps: carrying out AM demodulation on a VOR baseband signal to obtain a VOR envelope signal; processing the VOR envelope signal through band-pass filters BPF1, BPF2 and BPF3 to obtain a variable phase signal, a first reference phase signal, Morse code audio and air-ground communication voice; performing FM demodulation on the first reference phase signal to obtain a second reference phase signal; and carrying out amplitude normalization on the variable phase signal and the second reference phase signal, then carrying out Ref-Var phase discrimination to obtain a phase difference between the two signals, and converting the phase difference into an azimuth angle of the aircraft. By adopting the digital design, the use of analog devices is reduced, the system integration level is increased, higher angle measurement precision can be obtained, and the navigation performance required by civil aviation area navigation can be better met.

Technology for wireless transmission of messages to remote receiving devices is disclosed. The technology includes receiving a message for transmission, determining transmission parameters for transmission of the message, and transmitting the message to a remote receiving device according to the determined transmission parameters. The technology may also include encoding the message to effect message latency and may be employed for message transmission via the ionosphere or other atmospheric layer at frequencies in the Medium Frequency (MF), High Frequency (HF), or Very High Frequency (VHF) spectrum. Further, the disclosed technology may be employed for message transmission to effect low latency financial transaction execution, such as high speed high frequency trading.

In an example of an embodiment, a plasma processing apparatus includes a processing container, a stage, an upper electrode, an inlet, and a waveguide device. The stage is provided within the processing container. The upper electrode is provided above the stage, to interpose a space within the processing container. The inlet is configured to introduce high-frequency waves. The high-frequency waves are VHF waves or UHF waves. The inlet is provided at an end of the space in the lateral direction, and extends in a circumferential direction around a central axis of the processing container. The waveguide device is configured to supply high-frequency waves to the inlet. The waveguide device includes a resonator that provides a waveguide. The waveguide of the resonator extends in the circumferential direction around the central axis and extends in the direction in which the central axis extends to be connected to the inlet.

A resonant inverter has a switch network from which a phase signal is provided representing the phase of the switching signal. A resonant tank circuit is coupled to the first switch network output and provides a feedback signal comprising a resonance voltage across a circuit element of the resonant tank circuit. A reference current to be drawn from the input node is set and a reference phase is set based on the reference current. The switching signal for the switch network is controlled based on a phase difference between the resonance voltage and the phase signal, and based on the reference phase. This resonant inverter employs a phase modulation scheme as the control scheme for the switch network of a resonant inverter. This approach is suited for high and very high frequency operation of resonant converters, for example up to tens of MHz.

An antenna mountable to a window to provide non-destructive installation and removal therefrom. The antenna has a substrate of dielectric material having a first surface with patterned conductive material providing a main radiator and ground plane, and a back surface of patterned conductive material providing a feeding circuit, which capacitively conveys and receives, via the substrate, RF signals with the main radiator and ground plane. The main radiator and ground plane, and preferably the feeding circuit, are each radiating structures to achieve different frequency ranges, such as over VHF, UHF, and cellular bands, with wideband performance. The antenna is configured to resemble a semitransparent sunshade by the antenna body being perforated, through the front and back thereof, with holes enabling a majority of the antenna body to appear semitransparent for screening sunlight. One or more fixtures are utilized for detachably mounting the antenna along a surface of a window.

The present invention discloses a VHF data link simulation device based on software radio, which includes a controller; a vector signal transceiver connected to the controller; a VHF data link component connected to the vector signal transceiver; wherein the vector signal transceiver is used to receive the pulse signal sent by the VHF data link component and decode it to obtain a message according to the control of the controller, and to perform VDL encoding and up-conversion according to the configuration operation of the user to output the corresponding VHF data link signal; the pulse signal or the VHF data link signal is a VHF data link mode A signal or a VHF data link mode 2 signal. It can be seen that the present invention can realize the simulation of pulse signal sending and receiving of two VDL modes, and overcome the problems of low efficiency and incomplete functions of existing similar VHF data link simulation devices.

The utility model discloses a very high frequency iron tower which comprises a base and a lightning rod, the base is fixed on the ground and connected with a tower body, stairs capable of going up and down are arranged in the tower body, the tower body is provided with a platform for standing, the outer side of the platform is connected with an antenna support arm, the antenna support arm is connected with an antenna, and the lightning rod is connected with the tower body. The lightning rod is arranged in the middle of the top end of the tower body. According to the very high frequency iron tower, the antenna supporting arm is composed of the two transverse steel pipes and the vertical steel pipe, the transverse steel pipes of the antenna supporting arm are generally 80 mm steel pipes, the vertical steel pipe is generally 50 mm steel pipes, the width of the adopted steel pipes is larger, and the transverse steel pipes and the vertical steel pipe are welded together and are not connected through a detachable structure, so that connection is more stable; meanwhile, the upper and lower transverse steel pipes of the antenna support arm are welded to the platform, and the vertical steel pipe is welded to the other sides of the two transverse steel pipes, so that a square structure is formed by the vertical steel pipe and the side face of the platform, and the stability of the antenna support arm is improved.

The invention relates to the technical field of ship abnormity positioning, in particular to an abnormal ship identification method based on AIS very high frequency signals, which comprises the following steps: acquiring a current ship message and a historical ship message sent by a to-be-detected ship, and obtaining a monitoring base station and the position of the current ship message according to the current ship message, determining the actual message receiving number of the to-be-detected ship in unit time according to the historical ship message; acquiring positions of all base stations, and judging whether the to-be-detected ship meets ship detection preconditions or not; when it is determined that the to-be-detected ship meets the ship detection precondition, the number of actual receiving base stations actually receiving the current ship message and the number of base stations outside the range outside the preset range in the actual receiving base stations are obtained; and when the number of the base stations in the determined range is not zero, continuously monitoring the to-be-detected ship through the monitoring base station to obtain a plurality of ship messages, and judging whether the to-be-detected ship is an abnormal ship or not. The abnormal ship identification method is simple, efficient and high in accuracy.

There is provided a plasma processing method comprising: continuously introducing electromagnetic waves into a chamber of a plasma processing apparatus, the electromagnetic waves being VHF waves or UHF waves, the electromagnetic waves being introduced into the chamber so as to form standing waves within the chamber along a lower surface of an upper electrode of the plasma processing apparatus; periodically applying a negative voltage to the upper electrode while performing said continuously introducing the electromagnetic waves; and supplying a processing gas into the chamber only during a period in which the negative voltage is applied to the upper electrode.

The present invention relates to a nickel zinc copper ferrite for VUHF antenna applications. In particular to a composition and solid material particularly suitable for the manufacture of antennas suitable for operation in the very high frequency (VHF) band and the ultra high frequency (UHF) band or V / UHF, and to a method of manufacture and use thereof. The composition has the formula Ni a Zn b Cu c Co d Fe 2‑δ O4, wherein: 2(a+b+c+d)+3(2-δ)=80.05

The application discloses a lightning VHF interference positioning method based on an irregular array, relates to the lightning positioning field, and comprises the following steps: S1, acquiring the antenna positions of N station interferometers and calculating the time difference τ of a radiation source reaching all baselines ij ; S2, judging whether all the antennas are on the same plane, if yes, entering S3, otherwise, entering S4; S3, calculating the positioning direction of the radiation source by using M groups of baselines and entering S6; S4, combining any three stations to form a selection; S5, calculating the direction of the radiation source under each selection and determining the positioning direction of the radiation source; S6, calculating the elevation angle and the azimuth angle of the radiation source according to the positioning direction of the radiation source; when the interference positioning is performed, the non-coplanar characteristics of the antenna array and the increase of the number of antennas can obviously improve the positioning result of the interferometer, and the method can be applied to any irregular array, that is, the antenna array can be randomly arranged, the coplanar of the antenna array is not required, and the baselines formed by the antenna array are not required to be orthogonal to each other, so that the installation difficulty of the antenna is effectively reduced.