589 results about "Short Waves" patented technology

The invention discloses a medium-short wave signal transmission interference suppression method and system based on wireless radio and television, and the method comprises the following steps: S1, collecting and preprocessing medium-short wave frequency band data, and constructing a frequency spectrum state data set; s2, constructing a spectrum evolution cognitive map model based on the spectrum state data set; s3, performing clustering analysis by using the spectrum evolution cognitive map model to generate a broadcast interference popularity map; s4, inputting the spectrum evolution cognitive map model and the broadcast interference heat map into an improved badger interference avoidance algorithm, and outputting a frequency hopping avoidance path; s5, the broadcast transmitting system executes frequency hopping scheduling control according to the frequency hopping avoiding path, and it is guaranteed that frequency point switching is completed under the condition that broadcast service is not interrupted; and S6, the broadcast receiving terminal collects signal quality parameters and transmits the signal quality parameters back to the central system, and the node state of the spectrum evolution cognitive graph model is updated in real time. According to the method, active avoidance of medium-short wave broadcast interference and stable frequency hopping scheduling are realized by combining frequency spectrum cognitive modeling and a swarm intelligent optimization algorithm.

The invention relates to a visible light / short-wave infrared dual-band common-caliber optical system, which comprises a common-caliber part, a plane beam splitter, a visible light channel subsystem and a short-wave infrared channel subsystem, and is characterized in that the common-caliber part is positioned at the foremost end of the optical system and consists of a primary reflector and a secondary reflector which are coaxially arranged; the plane beam splitter is located on a light path behind the secondary reflector, full-wave-band light from an object side is reflected by the primary reflector and the secondary reflector in sequence, then reaches the plane beam splitter to be split, and then enters the visible light channel subsystem and the short-wave infrared channel subsystem to be imaged in different wave bands, and the optical system achieves dual-wave-band common caliber. According to the invention, the design of long focal length and large aperture of the dual-band system is realized, the target detection / identification capability of the system is improved, the system has the advantages of high spatial resolution, long operating distance and high identification probability, meanwhile, the system structure is effectively simplified, the system volume is reduced, the installation and adjustment difficulty is reduced, and a relatively low obscuration ratio and relatively high imaging quality are realized.

The utility model provides a power calibration system of a solid-state high-power AM short-wave transmitter, relates to the technical field of radio and television, and adopts the technical scheme that the system can quickly respond to power deviation and continuously adjust parameters of excitation signals through a control mechanism based on real-time feedback, so that the output power is accurately controlled. After the exciter unit receives the control signal sent by the computer, the optimized excitation signal can be generated, it is ensured that the input signal received by the power amplifier unit is adjusted in advance, and the power amplifier efficiency and the output signal quality can be improved. And the power amplifier unit amplifies the optimized excitation signal into a high-power radio-frequency signal and outputs the high-power radio-frequency signal to complete the whole power amplification process. Through cooperative work of the computer, the exciter unit, the power amplifier unit, the frequency spectrograph and the power meter, a closed-loop control system is formed, and high-precision and high-efficiency power calibration can be realized.

The invention relates to the technical field of rehabilitation instruments, in particular to a control method and system based on an ultra-short wave therapeutic instrument. The method comprises the following steps: acquiring illness state information and human body composition data of a user; the illness state information comprises a treatment part, and the human body composition data comprises a body fat rate, a water content and a muscle content; inputting the human body composition data and the illness state information into a trained treatment parameter recommendation model to obtain treatment parameters of the user; the treatment parameters comprise output power and treatment time, and the treatment parameter recommendation model is a machine learning model; and outputting the treatment parameters, so that the ultrashort wave therapeutic apparatus emits ultrashort waves corresponding to the treatment parameters. According to the method, the treatment parameters are automatically generated according to the actual situation of the user, and the treatment effect of the user is improved.

The invention provides a short-wave infrared detector digital alloy material and a preparation process thereof. The preparation process comprises the following steps: growing a GaSb buffer layer on the surface of an n-type GaSb substrate; starting a first In furnace, and growing an InAs layer on the surface of the GaSb buffer layer in cooperation with an As beam; starting a second In furnace, and growing a quaternary solid solution layer matched with a GaSb buffer layer lattice on the surface of the InAs layer in cooperation with the Ga furnace and the AsSb beam; and alternately growing an InAs layer and a quaternary solid solution layer on the surface of the quaternary solid solution layer to generate a superlattice structure until the total thickness of the superlattice structure reaches a set target thickness, thereby obtaining the digital alloy material. According to the digital alloy material for the short-wave infrared detector and the preparation technology of the digital alloy material, the short-wave infrared detector can be expanded to the wave band ranging from 2.4 micrometers to 2.8 micrometers at the 50% cut-off wavelength.

The invention provides a short-wave multi-mode hollow-core anti-resonance optical fiber and a preparation method thereof, and relates to the technical field of optical fibers, and the short-wave multi-mode hollow-core anti-resonance optical fiber comprises an outer sleeve and a plurality of anti-resonance units which are arranged along the circumferential direction of the inner wall of the outer sleeve in an array manner; a central cavity enclosed by the plurality of anti-resonance units forms a fiber core area; the anti-resonance unit comprises at least three layers of anti-resonance tubes with different radiuses and two supporting rods arranged between two adjacent layers of anti-resonance tubes; wherein the two supporting rods in each layer are oppositely and obliquely arranged in pairs by taking the radial direction of the optical fiber as a symmetry axis, and the supporting rods on the same side are sequentially arranged along the same radius of the anti-resonance unit. Therefore, the waveguide filter has the advantages of being suitable for the 850 nm wave band, and being capable of supporting more high-order guided modes while giving consideration to low loss.

The invention provides a maritime emergency lifesaving comprehensive management system and method, and belongs to the technical field of software communication, the system comprises a guarding platform, a comprehensive processing platform and at least one application platform, the guarding platform is used for receiving rescue information sent by a user and sending the rescue information to the processing platform; the guarding platform comprises a short-wave guarding station, an ultra-short-wave guarding station and at least one satellite ground station which are connected with the communication bearing network; the comprehensive processing platform is connected with the guarding platform through a communication bearing network; the comprehensive processing platform comprises a comprehensive processing module and a backup service module, and the comprehensive processing module is used for performing format conversion on the rescue information to obtain alarm information and distributing the alarm information to each application platform based on the distress position; the backup service module is used for storing alarm information; and each application platform is in communication connection with the comprehensive processing platform and is used for receiving the alarm information and pushing the alarm information to the front-end display platform.

The invention belongs to the technical field of short-wave communication, and particularly relates to a short-wave sky wave channel propagation parameter optimization method based on antenna directivity, which comprises the following steps: acquiring directivity diagrams of a transmitting antenna and a receiving antenna; determining a propagation path of sky wave rays from a transmitting antenna to a receiving antenna by adopting a numerical ray tracing algorithm; according to the propagation path, calculating free space propagation loss, ionosphere loss and ground reflection loss; performing directional gain correction on the signal intensity on the propagation path according to the directional diagrams of the transmitting antenna and the receiving antenna; calculating the total propagation loss according to the free space loss, the ionosphere loss, the ground reflection loss and the antenna directivity correction value; outputting propagation parameters including the total propagation loss, the propagation path, the antenna directivity correction value and the time delay; according to the method, antenna directivity parameters and propagation path loss are dynamically coupled, and the defect that a traditional model ignores the influence of antenna radiation directivity on signal strength is overcome.

The embodiment of the invention discloses a defect degree judgment method based on short wave excitation non-self-sustaining discharge, and relates to the technical field of electrical insulation detection, and the method comprises the steps: obtaining the non-self-sustaining discharge voltage of an insulator; obtaining a self-sustaining discharge voltage of the insulator; collecting a discharge signal of the insulator under a preset voltage, extracting at least two different discharge characteristic parameters from the discharge signal, and calculating to obtain a discharge activity comprehensive index representing the discharge activity degree; based on the non-self-sustaining discharge voltage and the self-sustaining discharge voltage, a voltage safety margin coefficient is obtained through calculation, and according to the voltage safety margin coefficient and the discharge activity comprehensive index, the defect hazard degree of the insulator is judged; by constructing a voltage safety margin and discharge activity two-dimensional evaluation model, early defects can be accurately identified, defect risks can be quantitatively evaluated, and the accuracy and reliability of evaluation are improved.

The invention discloses an earth surface downlink short-wave radiation space downscaling method based on a super-resolution reconstruction technology, belongs to the technical field of meteorological data analysis, and solves the problems of insufficient solar radiation data space resolution and weak earth surface heterogeneity characterization capability in the prior art. Carrying out super-resolution reconstruction on the radiation data set by adopting a super-resolution combination model, and carrying out weighted fusion on a reconstructed data set output by the super-resolution combination model; according to the method, the output results of the multiple models are subjected to weighted fusion, weight optimization of the super-resolution sub-models is performed in combination with the high-resolution terrain factors, spatial downscaling from 5km to 1km resolution is finally realized, the spatial precision of the solar radiation data is remarkably improved on the basis of keeping the hour-level time resolution of the original data, and the accuracy of the solar radiation data is improved. And more earth surface heterogeneity information can be captured, and meanwhile, the high-time-resolution application requirement is met.

The invention discloses a space short wave intelligent frequency selection system and a space short wave intelligent frequency selection method. The system comprises an airborne communication control system, an air-used short-wave radio station, an air-used short-wave antenna and laser inertial navigation equipment. The method comprises the following steps: an air-used short-wave radio station establishes a frequency forecasting model by using a machine learning technology according to time position information; the air-used short-wave radio station obtains a short-wave frequency band available frequency spectrum hole and puts the hole into a sky wave preselected frequency set, and a current passable frequency band is calculated in combination with a frequency forecasting model; the air-used short-wave radio station selects a frequency point with the minimum local electromagnetic interference from the preselected frequency set of the passable frequency band in combination with the local noise distribution condition to perform frequency selection and link establishment; the two parties store and sort the signal-to-noise ratios of the link establishment frequencies, and link establishment is completed if one pair of receiving and transmitting frequencies of the two parties meets communication requirements; and if not, returning to carry out the frequency selection process again until the frequency meeting the communication requirement is selected. According to the invention, automatic intelligent real-time frequency selection is realized, and the efficiency of frequency selection and link establishment and the passability of an air-service short-wave communication system are improved.

The invention discloses a short-wave time difference positioning method based on particle swarm optimization, which is realized by aiming at a short-wave signal source positioning problem under the condition that ionized layer information is unknown through the following steps of: dynamically screening a receiving station combination with optimal geometric distribution by adopting a particle swarm optimization algorithm based on longitude and latitude and time difference observation data of a receiving station group; taking the main receiving station as a coordinate origin, and converting the geographic coordinates of the selected station into rectangular plane coordinates; constructing a time difference positioning equation set by using a Chan algorithm, and calculating a target position through pseudo-inverse solution and an iteration strategy; and filtering the ill-conditioned solution based on a geometric accuracy factor threshold, analyzing a positioning point cluster through sliding window density, and outputting median coordinates as a final positioning result. According to the method, the receiving station is innovatively selected and modeled as a combinatorial optimization problem, the positioning precision in a complex electromagnetic environment is remarkably improved through a collaborative architecture of particle swarm optimization and a Chan algorithm, and the problem of positioning drift caused by poor geometric distribution of stations in a traditional method is effectively solved.

The invention belongs to the technical field of short-wave radio station control, and particularly relates to a foreign trade short-wave radio station remote control method based on a WiFi link. According to the method, through multi-round data feedback and strategy optimization, the problems of frequency deviation, insufficient power or overload are automatically corrected, the signal distortion and interruption rate are effectively reduced, the high reliability of a communication link is ensured, and based on real-time calculation of an environment interference coefficient and communication compensation information, the transmitting power can be dynamically improved or a more suitable modulation mode can be switched; therefore, the influence of electromagnetic noise on the signal is reduced, the data transmission quality is ensured, flexible adjustment can be performed according to different communication distances, bandwidth requirements or frequency band limitation through a dynamic control strategy, and the rapid deployment and switching requirements of the foreign trade short-wave radio station in multiple scenes are met.

The invention belongs to the field of wireless communication, and relates to a short-wave SC-FDM block iterative equalization method for residual inter-symbol interference cancellation, which comprises the following steps: acquiring a signal yn of a receiving end, and performing FFT (Fast Fourier Transform) on the signal yn to obtain a frequency domain signal Yk; performing feed-forward equalization and MMSE feedback equalization on the signal Yk to obtain a feed-forward equalization signal Zk and a feedback equalization signal Gk, 0; superposing the signals Zk, Gk, 0 to obtain an equalization signal Dk, 0; carrying out IFFT (Inverse Fast Fourier Transform) on the balanced signal Dk, 0 to obtain a time domain signal rn, 0; judging the signal rn, 0 to obtain a judgment signal # imgabs0 #, performing residual intersymbol interference estimation on the signal # imgabs1 #, obtaining a residual intersymbol interference factor # imgabs2 #, and performing feedback equalization on the frequency domain signal Yk according to the factor # imgabs3 # to obtain a feedback equalization signal Gk, 1; superposing the signal Zk and the signal Gk, 1 to obtain an equalization signal Dk, 1; carrying out IFFT (Inverse Fast Fourier Transform) operation on the balanced signal Dk, 1 to obtain a time domain signal rn, 1; according to the method, noise suppression and residual inter-symbol interference cancellation operation are respectively carried out from the time domain and the frequency domain in MMSE feedback equalization, so that the equalization precision is improved.

The invention provides a segmented adaptive gain-based short-wave band amplitude and phase control device and method, and relates to the field of short-wave intelligent control. The method comprises the following steps: performing coupling detection processing on N paths of input short-wave signals to obtain coupled short-wave signals and power values of the coupled short-wave signals; based on the coupled short-wave signal and the power value of the coupled short-wave signal, calculating adjustment parameters through a preset adaptive segmented multi-target differential evolution algorithm, wherein the adjustment parameters comprise a frequency correction parameter, a phase adjustment parameter and an amplitude control voltage; adjusting the coupled short-wave signal based on the adjustment parameter to obtain a target short-wave signal; and detecting whether the target short wave signal meets a preset output condition, and if the target short wave signal meets the preset output condition, coupling the target short wave signal to output a radio frequency output signal. Through the scheme, the communication quality is improved.

The invention discloses a novel floating breakwater-oscillating water column wave energy conversion device integrated system which comprises a breakwater assembly, the bottom of the breakwater assembly is fixed through an anchor chain, an air chamber is arranged in the breakwater assembly, the top of the air chamber is provided with an air hole pipeline, the air hole pipeline is connected with a turbine generator, and the turbine generator is connected with an oscillating water column wave energy conversion device. A permeable structure is fixed to the wave facing side of the breakwater assembly, and a gap is formed between the permeable structure and the breakwater assembly. A permeable structure, an oscillating water column wave energy device and a floating breakwater are integrated, the permeable structure is used for dissipating high-frequency short waves, reducing wave loads acting on the structure and improving the stability and survivability of the structure, and in order to improve the energy dissipation effect of the permeable structure, a certain distance is formed between the permeable structure and an air chamber structure; the OWC wave energy device is used for absorbing long-wave energy for power generation, and the blocking capacity of the integrated system to long waves is improved; through integration of the three, a basic platform is shared, sea area resources are saved, operation and maintenance cost is reduced, and diversification of functions of the integrated system is realized.

The invention designs a short-wave over-the-horizon communication comprehensive simulation analysis method for the problems of cascade and comprehensive analysis of antenna radiation characteristics and radio wave propagation environments. The method comprises the steps of performing radiation characteristic simulation on a short-wave antenna, constructing an ionosphere model, simulating a propagation path of a short-wave signal in an ionosphere by adopting a ray tracing technology, integrating antenna characteristics, an ionosphere environment and a propagation mechanism, and calculating falling area energy distribution of the signal. And comprehensive evaluation and analysis of the reachable range of short-wave beyond-visual-range communication are realized. According to the method, the signal propagation path and fading characteristics of the signal from the radiation source to the receiving tail end can be comprehensively mastered, and guidance and basis are provided for antenna selection, erection, coverage area analysis and communication quality estimation in practical engineering application of short-wave beyond visual range communication.

The invention relates to the technical field of wireless communication and signal processing, in particular to a short-wave spectrum efficient sampling method and system based on compressed sensing, and the method comprises the steps: collecting full-band power spectrum density data through a low-speed scanning receiver; determining a strong interference frequency point set; generating a binary null observation sequence; loading the binary null observation sequence to an analog front-end frequency mixing circuit, performing analog domain orthogonal frequency mixing and integral processing on the input radio frequency signal, and outputting a voltage sampling value; resolving to obtain a signal sparse coefficient through a compressed sensing reconstruction algorithm; calculating a reconstruction residual error according to the voltage sampling value and the signal sparse coefficient; in response to the condition that the reconstruction residual error is greater than a preset error threshold, triggering a reacquisition process of the power spectral density data; outputting a signal sparse coefficient in response to the condition that the reconstruction residual error is smaller than or equal to a preset error threshold; according to the invention, the problems of limited dynamic range and weak signal submerging are solved, and the receiving sensitivity of weak signals in a strong interference environment is obviously improved.

The invention provides a broadcast antenna ATU input standing-wave ratio automatic adjusting and testing system. A human-computer interface is used for setting a target working program, a working frequency band and initial inductance and capacitance values, and a tuned standing-wave ratio curve and inductance and capacitance values are displayed; the control module decomposes the input initial inductance and capacitance values into rotation turns required by the current motor, transmits the rotation turns to the transmission module, and sends a target working program to the original short-wave antenna system; the transmission module enables the motor to be located at a target position, and correspondingly, target inductance and capacitance values are achieved; the data acquisition module is used for testing the standing-wave ratio of the system, reading the current inductance and capacitance values, recording the maximum value of the standing-wave ratio and sending the maximum value to the data processing module; and the data processing module processes the data and judges whether the current standing-wave ratio meets the requirement or not. According to the method, the automatic test system and the automatic optimization algorithm are combined, so that the workload of debugging personnel is reduced, and the working efficiency of ATU tuning is improved.

The invention relates to the technical field of mobile communication base stations, and particularly discloses a short-wave antenna performance test system, which is used for testing the short-wave antenna performance of a mobile communication base station, and comprises a transmitter connected with a tested short-wave antenna and used for transmitting a single-frequency-point signal with a specified short-wave frequency and monitoring output forward power and backward power; the unmanned aerial vehicle is used for providing longitude, latitude and elevation of the center point of the short-wave antenna; the field intensity meter is carried by the unmanned aerial vehicle and is used for receiving the signal transmitted by the measured antenna and carrying out spectrum analysis and field intensity measurement operation, and the monitoring frequency setting of the field intensity meter comprises the transmitter frequency; and the ground monitoring terminal is used for collecting monitoring and measuring information of the unmanned aerial vehicle and the transmitter, calculating and drawing an antenna pattern by combining the antenna transmitting frequency and the field intensity acquired by the field intensity meter, and calculating gain. The problems that a short-wave antenna space directional diagram and gain are difficult to measure, and environment interference is caused are solved, and high-precision and full-space coverage short-wave antenna performance testing is achieved.

The invention relates to the technical field of short-wave selection, in particular to a data processing method and system in a short-wave communication system, and the method comprises the following steps: constructing a compensation matrix based on time-varying channel response, carrying out the multipath alignment of a received signal, and generating a preliminary equalization signal; sequentially carrying out time domain impulse noise suppression and frequency domain background noise correction on the preliminary equalization signal to generate a noise reduction signal; and according to a weighted evaluation result of the signal distortion degree and the noise residual quantity, dynamically adjusting a compensation matrix parameter and a noise reduction intensity coefficient to form closed-loop control. According to the invention, in a dynamic channel with a low signal-to-noise ratio, synchronous suppression of multipath interference and noise is realized, and signal distortion and redundancy overhead are avoided at the same time.

The invention relates to the technical field of electronic measurement, and discloses a software instrument system-based short-wave broadcast equipment power automatic calibration system, which comprises a main control unit, a signal excitation unit and a measurement feedback unit. According to the method, an iterative adjustment process is controlled through a main control unit; a measurement feedback unit measures the actual output power of a measured device; and the main control unit directly takes the power difference value as the adjustment amount of the excitation level according to the power difference value between the actual output power and the preset target power, adds the adjustment amount with the current excitation level to obtain the next excitation level, and controls the output of the signal excitation unit until the preset precision is met. According to the method, test link loss calibration is executed before iterative adjustment so as to compensate system errors, a calibration lookup table can be automatically generated after calibration is completed, the problems that a traditional calibration method is low in efficiency and insufficient in precision are solved through an adaptive adjustment strategy and system error compensation, and the calibration accuracy is improved. The method has the beneficial effects of high convergence speed, accurate calibration result and high automation degree.

The invention belongs to the technical field of short-wave communication channel modeling, and discloses a short-wave channel modeling method and system based on signal wavefront recovery, and the method comprises the steps: projecting standard plane waves to an antenna array from different angles through a cooperative target radiation source, collecting antenna array signals in different directions under the condition of no disturbance, and storing the signals as calibration data; calculating the time delay of each antenna before receiving the wavefront relative to the center of the antenna array, calculating the relative time delay of the time delay and the calibration data, and multiplying the relative time delay by the wavelength to realize the time domain-space domain conversion of wavefront distortion to obtain wavefront slope distribution; and calculating the size of a Zernike polynomial coefficient of each order based on wavefront slope distribution, analyzing specific components of aberration contained in signal wavefront, and performing wavefront fitting reconstruction so as to complete short-wave channel modeling. According to the method, the Zernike polynomial is adopted to fit the wavefront disturbance quantity, the influence of the ionized layer on the wavefront of the short-wave signal is quantified in real time, and a high-precision channel model is constructed.

The invention relates to a method and a device for disinfecting a surface of an object or of a medium flowing in a cavity by irradiating it with electromagnetic radiation which lies in the visible wavelength range, wherein the colour or wavelength of the electromagnetic radiation is switched at short time intervals between two values, one of which lies in the shorter-wave, blue part of the visible spectrum and the other in the longer-wave, red part of the visible spectrum.

The invention relates to the technical field of transmit-receive converters, in particular to a short wave transceiver common antenna transmit-receive converter based on a PIN diode. The transmit-receive converter comprises a power control module used for monitoring the output power of a power amplifier in real time and dynamically adjusting the output power through a variable attenuator; the cooperative control unit is configured to adjust the attenuation amount of the output power according to the power control module; determining an adjustment strategy of a pre-distortion coefficient in a digital pre-distortion algorithm; and the digital pre-distortion module is used for determining a pre-distortion coefficient in a digital pre-distortion algorithm according to the adjusted output power and the integer strategy so as to compensate nonlinear distortion of the power amplifier through the pre-distortion coefficient.

The present invention discloses a method for modeling a large-scale MIMO wireless channel in the short-wave band. The specific steps are as follows: 1) Calculate the distance ranges of three short-wave communication propagation modes, and determine the short-wave communication propagation mode in the current environment; 2) Conduct frequency prediction to obtain the current optimal operating frequency; 3) Conduct large-scale channel parameter modeling; 4) Conduct small-scale channel parameter modeling; 5) Conduct space-time-frequency non-stationarity modeling; 6) Analyze the channel statistical characteristics and verify the model. Due to the limited short-wave communication spectrum resources and the severe ionospheric channel conditions, the system rate is relatively low. Most of the existing short-wave channel models are point-to-point small-scale MIMO, and the system rate gain is not obvious. The present invention establishes a method for modeling a large-scale MIMO wireless channel in the short-wave band, which can support communication scenarios with large-scale MIMO antenna configurations and is compatible with three short-wave communication propagation modes. The wireless channel model based on the present invention has guiding significance for the construction and performance analysis of short-wave large-scale MIMO wireless communication systems.

The invention relates to the technical field of communication, in particular to a method for enhancing spurious frequency suppression in short-wave multi-channel reception, which comprises the following steps of: after converting a collected short-wave radio-frequency signal into a digital signal, respectively processing the digital signal through a first channel and a second channel, the first channel carries out filtering preprocessing on the digital signal to obtain a preprocessed signal, and then carries out down-conversion processing on the preprocessed signal to obtain a first baseband signal; the second channel performs down-conversion processing on the digital signal to obtain a second baseband signal; multichannel processing is carried out on digital signals at the same time, the application scene of short-wave broadband high-data-rate multi-channel down-conversion processing can be supported, the requirement for simultaneous receiving of short-wave multi-channel frequency points is met, each far-end interference source can be filtered through multi-channel digital resonance processing, and the receiving efficiency is improved. And the spurious suppression capability during digital down-conversion processing is enhanced.

The invention discloses an impedance matching feed adapter for a ship-borne short-wave antenna, and belongs to the technical field of short-wave antennas. The impedance matching feed adapter comprises a supporting assembly and an impedance matching assembly. The supporting assembly comprises a supporting base, an insulating shell, an insulating frame and an insulator, the supporting base is detachably connected with the insulating shell to form a cavity, the insulating frame is inserted into the cavity, and the insulator is inserted into the supporting base; the impedance matching assembly comprises a core column, an impedance matching coil and a feed connector, the core column is inserted into the insulator, the impedance matching coil is spirally wound on the periphery of the insulating frame, and the feed connector is inserted into the top of the insulating shell. The impedance matching feed adapter for the ship-borne short-wave antenna provided by the invention can integrate an insulating support function and an impedance matching function, can realize reliable insulating support between the short-wave antenna and a ship deck, and also can ensure that the short-wave antenna has good impedance matching in a working frequency band.

The present invention discloses a short-wave infrared telescope for short-distance detection, which is a coaxial transmissive optical system with a working wavelength range of 1000nm to 2500nm. It includes a window glass and eight spherical lenses. Along the light incident direction, they are successively the first plane window plate, the second negative meniscus lens, the third positive meniscus lens, the fourth positive meniscus lens, the aperture stop, the fifth positive biconvex lens, the sixth negative meniscus lens, the seventh positive biconvex lens, the eighth negative biconvex lens, and the ninth positive biconvex lens. The present invention is applicable to the short-wave infrared band of 1000nm to 2500nm; applicable to short detection distances of 1050mm to 1500mm; has a large viewing angle and a small system volume; the image-space telecentric system makes the image plane illumination uniform and is easy to be spliced with the spectrometer splitting system; within the range of -10°C to 40°C, the imaging quality is close to the diffraction limit; the processing and manufacturing costs are low; the energy utilization rate is high, the light-gathering ability is strong, and the thermal adaptability is good.

The invention belongs to the technical field of radio frequency amplification circuits, and particularly discloses a short-wave receiving amplification circuit capable of realizing cascade transmission and a short-wave communication system. According to the invention, direct current and interference in a previous-level signal are filtered through the filtering module, a pure radio frequency signal is obtained, and a foundation is laid for subsequent processing; the signal strength is improved through the amplification module, and single-stage transmission attenuation is overcome; the key point is that the balance gain module applies gain processing which is compensated for the loss characteristic of a transmission link to the amplified signal, so that the signal strength can be accurately matched with the actual loss of the line, and the problem that a fixed gain mode cannot adapt to the multi-stage series accumulated loss is solved. Compared with the prior art, the scheme realizes stable cascade transmission of short-wave signals through cooperative work of the modules, and remarkably improves the transmission distance and reliability of the system through dynamic compensation accumulated loss.