711 results about "Down conversion" patented technology

The invention discloses an adaptive modulation anti-multipath unmanned aerial vehicle swarm communication method and system based on MIMO-OFDM, and relates to the technical field of wireless communication, and the method comprises the steps: receiving a down-conversion baseband; synchronization and compensation are carried out; removing a cyclic prefix and carrying out fast Fourier transform; estimating a channel and noise on the training and pilot frequency, and correcting a common phase; performing frequency domain equalization and soft decision, forward error correction and cyclic redundancy check according to the estimation to obtain a control parameter, decoding a payload according to the control parameter, and performing statistics to form a link quality indication; modulating coding, bandwidth and spatial mode, configuring mapping, power and weight, and packaging physical layer protocol data; carrier sensing conflict avoiding sending, confirmation and retry are adopted to generate media access statistics; and the routing selects the next-hop multi-hop forwarding according to the transmission quality, and performs end-to-end statistics and recharge. Through cooperation of hierarchical synchronization and phase correction with cyclic prefix and FFT, crosstalk is suppressed, channel noise scale optimization soft decision is robust, data decoupling is controlled, and end-to-end availability is improved through multi-hop self-healing recharge.

The invention relates to the technical field of ground resistance detection, in particular to a single-core cable ground resistance detection method capable of resisting strong power frequency interference. High-frequency signals are injected in a non-contact mode through a coupling type capacitor clamp, background voltage and current signals are collected firstly, and injection frequency far away from power frequency and harmonic waves is selected through Fourier analysis; cancelling background noise by adopting a normalized least mean square adaptive filter to generate an enhanced signal; the signal is down-converted to a base band through digital quadrature demodulation, a Kalman filter estimates the amplitude and the phase in real time, and the state and noise parameters are periodically calibrated through a compressed sensing algorithm; and finally, loop impedance is calculated according to the voltage and current amplitudes and the phase difference to obtain grounding resistance. The method has the advantages of being non-contact, high in safety, strong in anti-interference capability, high in measurement precision and the like, and is suitable for monitoring the grounding state of the cable in a complex electromagnetic environment.

The invention relates to the technical field of signal analysis, in particular to a GNSS (Global Navigation Satellite System) detection method and system based on machine learning, and the method comprises the steps: receiving a navigation radio-frequency signal containing reality and deception, and carrying out the down-conversion of an RF (Radio Frequency) front end to obtain intermediate-frequency data; gNSS signal capture is completed by searching correlation peaks in frequency and code phases based on intermediate frequency data; in the capturing stage, a motion state, a correlation peak number, a noise value, capturing parameters and peak + / -1 chip sampling features are extracted and input into a machine learning classification model to judge whether cheating exists or not; if so, separating the deception signal from the real signal, and respectively sending the deception signal and the real signal into independent tracking channels; measuring an array element carrier relative phase by an array antenna, establishing a phase center model, and correcting to obtain an effective phase center and a differential baseline; according to the method, a deception azimuth angle and a pitch angle are obtained, a beam weight is calculated, a deception direction is subjected to null setting, a real direction is subjected to main lobe protection, and a weight value is fed back in real time to improve a signal carrier-to-noise ratio and locking stability. According to the invention, the problem that the existing commercial GNSS signal is low in power and easy to be interfered by deception is solved.

The invention discloses a communication-detection integrated sonar signal design method and device based on multi-pulse composite modulation, and the method comprises the steps: dividing a total frame period into a detection sub-frame and a communication sub-frame, enabling the detection sub-frame to achieve the high-resolution distance measurement through employing a bidirectional linear frequency modulation (BILFM) signal, a communication sub-frame adopts a multi-frequency multi-phase composite modulation (MTPM) signal to realize high-bit-rate data transmission; after band filtering, orthogonal demodulation, low-pass filtering and down-sampling preprocessing are carried out on detection sub-frame echoes, distance and speed information is extracted by adopting fast-time low-sampling two-dimensional fast Fourier transform (2D-FFT), unambiguous Doppler frequency is recovered by utilizing the Chinese remainder theorem (CRT), and accurate speed measurement of long-distance and high-speed targets is realized; a communication subframe receiving signal is subjected to IQ demodulation after down-conversion, Costas loop carrier synchronization and matched filtering, and multi-frequency multi-phase coded data are extracted. According to the method, the time-frequency collaborative design of detection and communication is realized, the distance resolution and the speed measurement range are considered, and the signal bandwidth utilization rate and the underwater information transmission reliability are remarkably improved while the system complexity is kept low. The device comprises a processor and a memory, and an executable program for implementing the method is stored in the memory. The technology can be widely applied to the fields of unmanned underwater vehicles, ocean monitoring, underwater sensing networks and the like.

The invention relates to a low-orbit satellite short burst signal high-precision capturing method and device, equipment and a medium. The method comprises the following steps: sequentially carrying out digital down-conversion and L-time signal pseudo code rate down-sampling on a low earth orbit satellite short burst signal sequence sampled by an ADC (Analog to Digital Converter) to obtain a down-sampled signal sequence; performing pre-accumulation processing on the down-sampling signals of every adjacent L points in the down-sampling signal sequence, and performing coarse capture on the pre-accumulated signal sequence by adopting a PMF-FFT algorithm to obtain a coarse pseudo code phase and a coarse frequency offset value; and performing serial code phase search on the down-sampling signal sequence based on the coarse pseudo code phase and the coarse frequency offset value, optimizing to obtain a fine pseudo code phase, and optimizing the estimation precision of the coarse frequency offset value according to the fine pseudo code phase and a frequency offset estimation algorithm based on a phase relation to obtain a fine frequency offset value. By adopting the method, the acquisition precision and speed of the short burst signal of the low-orbit satellite can be improved.

The invention discloses a self-adaptive CPFSK multi-symbol incoherent demodulation method, and belongs to the field of communication signal processing. The implementation method comprises the following steps: initializing a receiving signal and the length of an observation window; performing orthogonal down-conversion on the received signal to obtain a baseband received signal; constructing a local template sequence according to the length of the observation window, and performing baseband modulation to generate a local baseband template signal; according to the baseband receiving signal and a local baseband template signal, constructing an incoherent judgment statistic, and selecting a candidate sequence; classifying the candidate sequences into credible sequences and uncredible sequences by comparing the judgment of the candidate sequences before and after about the same symbol; taking an intermediate symbol of the credible sequence as an incoherent judgment result, and adding one to the position of the symbol to be judged; for an untrusted sequence, the length of an observation window is expanded, a candidate sequence is selected again, an intermediate symbol is used as a new incoherent judgment result, the position of a symbol to be judged is increased by one, iteration is repeated, and self-adaptive multi-symbol incoherent demodulation is achieved.

The invention relates to the technical field of radio frequency, in particular to a radio frequency conversion assembly, and the assembly comprises a baseband processing unit which employs a millimeter wave SoC chip and is used for generating and processing an initial transmitting signal of 79-81GHz and an initial receiving signal of 79-81GHz; the frequency conversion unit comprises an up-conversion subunit and a down-conversion subunit, and the local oscillation synthesis unit is used for generating and providing a local oscillation signal with a fixed frequency; the mode switching and processing system is used for selectively performing down-conversion processing on the echo signal or a target radio frequency signal from an external non-cooperative irradiation source in two working modes and then transmitting the echo signal or the target radio frequency signal to the baseband processing unit; the working mode comprises an active mode and a passive mode.

The invention relates to a time domain broadband adaptive beam forming method and system based on Chebyshev weighting, and belongs to the field of array signal processing. Aiming at the technical problems of poor real-time performance and high sidelobe of the existing broadband beam forming, the method comprises the following steps of: dividing a received broadband signal into a plurality of sub-bands, obtaining an optimal weight vector for each sub-band by adopting a minimum linear constraint iterative algorithm after down-conversion, constructing an expected response of an FIR filter according to each weight, obtaining a filter coefficient through L2 norm convex optimization, and finally obtaining a high sidelobe beam according to the expected response of the FIR filter. And performing time domain weighting on each array element signal by using a filter bank, and outputting a directional beam. According to the method, the calculated amount is low, a main lobe and interference null can be formed in real time in a broadband, and a certain side lobe height is kept.

The invention relates to a radio frequency transceiving multichannel amplitude-phase calibration system, which comprises a radio frequency receiver, a radio frequency transmitter, a data converter, an FPGA (Field Programmable Gate Array) processor and a clock network, wherein the radio frequency receiver adopts a zero intermediate frequency architecture and is used for receiving a multichannel radio frequency signal and down-converting the multichannel radio frequency signal into an analog baseband signal; the radio frequency transmitter adopts a zero intermediate frequency architecture and is used for up-converting the analog baseband signal into a radio frequency signal and transmitting the radio frequency signal; the data converter is connected with the radio frequency receiver and the radio frequency transmitter and is used for realizing conversion between an analog signal and a digital signal; the FPGA processor is connected with the data converter through a JESD204B interface and is used for aligning the data of each receiving and transmitting channel; and the clock network consists of a clock chip with JESD204B characteristics and a clock Buffer, and is used for providing a synchronous clock and an SYSREF signal for the whole system and supporting an SYNC synchronous trigger signal. By adopting the method, the problem of multi-channel amplitude-phase consistency can be solved.

The invention relates to a 92GHz MIMO roadside radar radio frequency system based on a frequency conversion assembly, and the radar radio frequency system comprises a baseband processing layer which comprises at least two cascaded millimeter wave system-level SoC chips; the frequency conversion layer is a frequency conversion module FCM, and the FCM comprises a local oscillator synthesis unit, an upper mixer group and a lower mixer group; the local oscillation synthesis unit is used for generating a 13GHz local oscillation signal; the input end of the upper mixer group is connected with the output end of the baseband processing layer, the local oscillation end of the upper mixer group is connected with the local oscillation synthesis unit, the output end of the lower mixer group is connected with the input end of the baseband processing layer, and the local oscillation end of the lower mixer group is connected with the local oscillation synthesis unit; and the down-conversion layer is used for down-converting 92-94 GHz echo signals received by the antenna array to 79-81 GHz and then outputting the echo signals to the baseband processing layer. According to the invention, 92-94 GHz frequency conversion can be realized.

A measurement and control simulation device based on a measurement and control data transmission integrated system comprises an upper computer display control test module, a PC host module, a signal processing master controller module, an isolation DC / DC module, a down-conversion module, a filtering module, an isolator module and an outer end face interface module. The system has the characteristics of multiple modulation systems, a spread spectrum function, controllable output power, Doppler frequency change and the like, can be used for simulating a star chain control system link test in a ground test system, and fully improves the index assessment performance during system docking; meanwhile, the design of a down-conversion link meets the requirements for the strength and sensitivity of the received signal, the stability and accuracy of the radio-frequency signal after frequency conversion in a low-power injection state are remarkably improved, and a new scheme is provided for a high-frequency conversion mode. Besides, the display control module of the equipment has the functions of multiplexing, reconstruction, multi-data interaction and the like, so that multifunctional and multi-task full-system test coverage can be realized, the cost investment of test systems such as spacecrafts and the like is greatly reduced, and the multifunctional index test coverage efficiency is improved.

The invention relates to the technical field of data processing, and discloses an integrated reconnaissance interference method and system based on a transmit-receive cancellation technology, and the method comprises the steps: receiving a mixed signal containing a target radar signal and a leakage interference signal through a receiving channel, and obtaining a first digital signal after down-conversion and analog-to-digital conversion, the leakage interference signal is a signal leaked from the transmitting channel to the receiving channel; acquiring a second digital signal corresponding to an interference signal generated in the transmitting channel, and transmitting the interference signal through an antenna after digital-to-analog conversion and up-conversion; taking the second digital signal as a reference signal, performing adaptive cancellation processing on the first digital signal through an adaptive filter to suppress a leakage interference signal component in the first digital signal, and generating a cancelled signal; wherein in the adaptive cancellation processing process, the digital processing unit adaptively updates the cancellation filtering weight of the adaptive filter according to the reference signal and the cancelled signal.

The invention discloses a multichannel broadband receiver, and belongs to the technical field of microwave radio frequency and electronic control, the multichannel broadband receiver comprises a multichannel down-conversion assembly, a local oscillator power component, a power interface control panel and a VPX connector, the down-conversion assembly adopts a cavity-divided integrated structure, multiple identical radio frequency links are arranged in the same cavity in parallel, and the VPX connector is connected with the local oscillator power component. Down conversion from a 2-18GHz radio frequency signal to a 1.3-2.3 GHz intermediate frequency signal is realized through two-stage frequency mixing; the power supply interface control board takes an FPGA as a core, integrates the functions of multi-path power supply conversion, driving isolation, state monitoring and the like, and realizes channel gain power failure storage and calling, BIT self-inspection, nanosecond rapid turn-off and multi-parameter real-time monitoring through software and hardware cooperation. Through collaborative innovation of the structure, circuit and control, high integration, high channel consistency, high isolation and high intelligence of the multi-channel receiver are realized, and the multi-channel receiver is suitable for the fields of high-performance radars, electronic countermeasures and the like.

The invention belongs to the technical field of full-duplex communication, and particularly discloses a high-isolation full-duplex transceiver system and a control method.The system comprises a transmitting module, a receiving module and a full-duplex baseband module, the transmitting module comprises a power amplifier module and a first oscillator, the power amplifier module is connected with the full-duplex baseband module, and the first oscillator is connected with the receiving module; an intermediate frequency signal transmitted by the full duplex baseband module enters the power amplifier module, is mixed with a signal with a frequency f4 generated by the first oscillator, and is up-converted to a frequency f3; the receiving module comprises a second oscillator and a low-noise amplifier module, the second oscillator is connected with the low-noise amplifier module, a receiving antenna of the receiving module receives the signal and inputs the signal into the low-noise amplifier module for frequency mixing with the signal of the second oscillator, the signal is down-converted to frequency f2, and the signal enters the full-duplex baseband module for data processing. By adopting the technical scheme, based on each module, the influence of self-interference leaked by a transmitting link on a receiving link is completely avoided, and the design complexity of any system is not increased.

The invention discloses a GNSS interference detection method based on NMF-SSA, and relates to a GNSS interference detection method. The invention aims to solve the problems of low detection probability, poor precision and poor adaptability to different types of interference in the existing satellite navigation signal interference detection method. The method comprises the following steps: 1, acquiring a satellite navigation signal from a radio frequency front end, and carrying out frequency mixing processing on the satellite navigation signal to obtain a down-conversion complex sampling sequence; performing amplitude normalization on the complex sampling sequence to obtain a target frequency band; performing short-time Fourier transform on the target frequency band to obtain a complex spectrum; obtaining a non-negative matrix based on the complex spectrum; processing the non-negative matrix to obtain a normalized matrix and meta-information of the normalized matrix; 2, constructing an activation aggregation sequence; 3, outputting binary judgment based on the reconstruction energy and the threshold value of the signal; the satellite navigation signal has an interference signal, and the satellite navigation signal has no interference signal. The method is applied to the field of satellite navigation signal interference detection.

The invention particularly relates to a method for converting pseudo code capture into tracking phase compensation under clock frequency offset. The method comprises the steps of band-pass sampling and digital down-conversion, local pseudo code sequence generation, twice pseudo code capture and phase compensation. Selecting a sampling frequency and processing a signal through a band-pass sampling theorem, and generating a local pseudo code based on a Gold code; a PMF-FFT method of a mobile pseudo code is adopted to complete first-time pseudo code capture, a multiplexing capture module executes second-time full-range capture, and pseudo code phase offset is accurately calculated; and finally, adjusting the local pseudo code phase through the total phase compensation value, so that the phase difference between the input signal and the local pseudo code is controlled within a half chip. According to the method, hardware cost does not need to be increased, the problem of inaccurate phase compensation under clock frequency offset, large frequency offset and low carrier-to-noise ratio scenes is effectively solved, it is guaranteed that pseudo code capture is smoothly converted into tracking, and the tracking reliability of a receiver is improved.

The invention provides a handheld radio multi-mode signal rapid detection method and system, and relates to the technical field of radio, and the method comprises the steps: collecting a radio frequency signal, and carrying out the down-conversion to obtain a baseband signal; digitally sampling to obtain a digital signal sample; time domain and frequency domain features are extracted through convolution kernels of different scales based on a deep learning network; determining a modulation mode and selecting a demodulation scheme, and automatically switching to an alternative scheme when the performance of a main demodulation scheme is poor; and comparing the demodulated signal with a signal feature library to determine and display the signal type. According to the invention, the multi-mode signal detection efficiency and accuracy are improved, and the equipment complexity is reduced.

The invention discloses a chirp spread spectrum photon terahertz communication perception integrated system. The system comprises a coherent light source module used for generating two beams of coherent single-frequency optical carrier signals; the signal modulation module is used for generating a baseband chirp spread spectrum communication sensing integrated signal and modulating the signal to one beam to form a carrier signal; the integrated signal transmitting module is used for taking the other beam of single-frequency optical carrier signal as an optical local oscillator signal, and after the optical local oscillator signal is coupled with the carrier signal, a terahertz communication sensing integrated signal is generated and radiated through optical down-conversion; the communication receiving module is used for performing frequency conversion and demodulation on the received terahertz communication sensing integrated signal and recovering communication information in the signal; and the radar receiving module is used for performing de-chirp and target information estimation on the received terahertz communication sensing integrated signal. According to the system, the advantages of a photon terahertz architecture are fully exerted, and an ultra-wideband chirp spread spectrum integrated signal is generated, so that a communication sensing integrated system with high spread spectrum gain and high energy efficiency is realized.

A down-sampling function folds the thermal noise into a lower frequency band. A capacitor samples a voltage during a period of bus inactivity and supplies the sampled voltage to an input of operational amplifier in a loop filter of a phase-locked loop when the bus is active. The sampling frequency determines the reduction in thermal noise that can be achieved. The PLL generates a clock signal for a bus. A voltage generator charges the capacitor through a transistor when the bus is inactive. The transistor turns on responsive to the bus being inactive to allow the capacitor to charge and the transistor turns off responsive to the bus being active to isolate the capacitor and operational amplifier from the voltage generator. When the bus is active, the voltage across the capacitor is supplied to the operational amplifier.

The invention discloses a multi-channel integrated radio frequency system based on double-threshold interference detection and dynamic spectrum aggregation. A radio frequency front-end unit is used for realizing broadband spectrum access and performing analog-to-digital conversion; the digital channel processing unit is used for realizing channelized segmentation through up-conversion and down-conversion, carrying out band elimination filtering to shield unavailable channels and outputting filtering parameters to support dynamic channel recombination; the digital signal parallel processing unit performs parallel access by using the divided channels; the spectrum sensing unit is used for carrying out double-threshold channel interference detection and real-time spectrum analysis according to the parallel access signals; and the frequency spectrum decision-making unit is used for judging the channel state and fusion detection judgment according to the interference detection result, judging the availability of a specific channel in the data link network and carrying out cooperative dynamic frequency spectrum aggregation. According to the method, a consistent spectrum access decision is realized by adopting a spectrum monitoring, sensing convergence and fusion decision mechanism, and consistent understanding of an available frequency set and high-reliability network domain dynamic spectrum aggregation are guaranteed.

A wireless communication device includes a processor to determine signal characteristics of digitized down-converted signals across first intermediate frequency band and second intermediate frequency band based on spatial analysis on the digitized down-converted signals. The processor perform cross-band correlation between the digitized down-converted signals across the first intermediate frequency band and the second intermediate frequency band. The processor detects jamming signal and jammer type in digitized down-converted signals based on cross-band correlation and determined signal characteristics of the digitized down-converted signals. The processor applies spatial nulling to multiple-input-multiple-output (MIMO) antenna array to dynamically suppress jamming signal when jammer type is spatial jammer. The processor activates jammer defense function to switch communication to unaffected intermediate frequency band when jammer type is non-spatial jammer and jamming signal is detected on primary intermediate frequency band and perform cross-band validation on digitized down-converted signals to confirm mitigation success of jamming signal.

The invention discloses a burst frequency hopping communication system high-precision arrival time estimation method, device and medium, and relates to the field of burst communication system time synchronization, and the method comprises the following steps: a receiving end carries out multi-channel down-conversion and double symbol sampling on a frequency hopping signal, and carries out local sequence correlation processing; aligning related results according to the frequency hopping pattern and the delay difference, performing non-coherent accumulation, and recording frame header stamping time at a peak moment; performing linear fitting on a correlation peak result to calculate a timing error estimation value; querying and obtaining corresponding compensation time by using an offline established time compensation table to correct the timing error estimated value, and obtaining a timing error precise estimated value; and finally, compensating the precise estimation value to the frame header stamping time, and outputting high-precision arrival time. According to the invention, high-precision time synchronization is realized at a low sampling rate, and hardware overhead is effectively reduced.

A wireless communication device includes a MIMO antenna array with dual-polarized antennas to receive RF signals in vertical and horizontal polarizations across a plurality of frequency bands. The received RF signals are filtered to isolate signals-of-interest, down-converted and digitized to obtain digitized down-converted signals. The wireless communication device includes a processor to concurrently process the digitized down-converted signals based on configuration of multi-link operation (MLO) parameters in the wireless communication device. The processor performs cross-band correlation between the processed digitized down-converted signals of the first intermediate frequency band and second intermediate frequency band to identify related signal patterns. The processor classifies detected signals based on the cross-band correlation, null steering, and an angle-of-arrival information and controls the wireless communication device to trigger an operational response based on the classified signals and the cross-band correlation.

The invention discloses an industrial mechanical arm tail end displacement high-precision detection method based on photoelectric interference, and relates to the technical field of precision measurement and detection, and the method comprises the steps: S1, collecting a photoelectric interference signal, and carrying out down-conversion filtering to obtain a complex envelope signal; s2, calculating an initial displacement observation value based on a complex envelope signal accumulation phase; s3, collecting equipment information to construct a sensing data set, and generating a multi-source error state vector; s4, eliminating errors by using extended Kalman filtering to generate a purification displacement value; and S5, the air refractive index is calculated according to the real-time environment parameters, the purification displacement value is compensated by combining the reference air refractive index, and a corrected displacement value is generated. Through multi-source sensor fusion, Kalman filtering error estimation and air refractive index compensation, high-precision, stable and robust measurement of the tail end displacement of the industrial mechanical arm is realized.

The invention relates to the technical field of wireless communication, and provides a low-noise down-conversion signal processing method and system, and the method comprises the steps: collecting an I / Q baseband signal, carrying out the processing of a signal branch and a mirror image branch of a dual-branch decoupling convolutional neural network, and obtaining a signal feature vector and a mirror image feature vector; decomposing the feature vector into a real part, an imaginary part, amplitude and phase components, and constructing a state vector by combining temperature, frequency and device parameters; inputting the state vector into a radio frequency sensing deep reinforcement learning network to output a gain control strategy; environment change is monitored through the meta-learning network, and network weight is adjusted based on performance feedback; and regenerating a final gain control strategy by using the updated weight, controlling the variable gain amplifier to carry out gain adjustment on the I / Q signal, and outputting a signal after low-noise gain control. According to the invention, low-noise, high-precision and adaptive gain control processing of I / Q baseband signals in a complex radio frequency environment is realized, and the signal-to-noise ratio and control precision of down-conversion signals are improved.

The application discloses a handheld spectrum analyzer real-time spectrum signal processing system and processing method, the system comprises a pre-processing unit, an ADC unit, an FPGA and an ARM which are connected in sequence, the FPGA comprises a digital down conversion unit, a multi-rate decimation filter unit, a real-time FFT operation unit and a real-time detection unit which are connected in sequence, and a grid mapping unit, a vector connection unit and a fluorescence statistical unit which are connected with the real-time FFT operation unit in sequence, the ARM comprises a real-time spectrum diagram and waterfall diagram unit which is connected with the real-time detection unit, and a fluorescence display unit which is connected with the fluorescence statistical unit. The application adopts parallel frame real-time detection and vector connection-based digital fluorescence statistical method to compress multiple spectrum data, reduces the requirement of a large number of spectrum data on screen refreshing, adopts vector connection to make fluorescence statistics, so that the measured signal is easier to distinguish, and the application meets the test requirement of a handheld instrument.

The invention discloses a signal reading system and method for superconducting microwave multiplexing device detection, and belongs to the field of superconducting microwave multiplexing device detection, and the system comprises a server which can issue a detection configuration instruction to a signal board, receive and return detection data, operate detection software, execute spectrum analysis and data analysis, and generate a detection result; the signal board is provided with a circuit containing a programmable logic device, and the circuit can output accurate intermediate frequency signals and excitation current signals according to instructions of the server, processes output signals of the detected superconducting microwave multiplexing devices mixed by the frequency mixing board through a critical sampling filter bank algorithm to obtain detection data, and transmits the detection data back to the server; and the frequency mixing plate can perform up-conversion on the intermediate frequency signal generated by the signal plate to radio frequency to form a radio frequency detection signal, output the radio frequency detection signal to each detected superconducting microwave multiplexing device, perform down-conversion on the radio frequency response signal returned from each superconducting microwave multiplexing device to intermediate frequency, and output the radio frequency response signal to the signal plate. The system can detect the quality of the device with low computing resources.

The invention relates to a multichannel down-conversion chip, a multichannel down-conversion circuit and a receiver, and the chip comprises a local oscillator signal processing module which accesses a local oscillator signal, carries out the amplification and power division of the local oscillator signal, and obtains a plurality of local oscillator power division signals; based on the local oscillator power division signal, phase shifting is carried out to obtain a phase-shifted local oscillator signal, and the phase-shifted local oscillator signal is input of a frequency mixer in a corresponding channel; each channel of the multi-channel module is provided with a radio frequency amplifier, a frequency mixer and an intermediate frequency amplifier which are connected in sequence, the input end of each radio frequency amplifier is used for accessing a received radio frequency signal, and the output end of each intermediate frequency amplifier is the output end of the corresponding channel; by adopting the chip, the number of components required in the down-conversion circuit can be effectively reduced, the manufacturing cost of the down-conversion circuit is reduced, and the plurality of components such as the radio frequency amplifier, the frequency mixer and the intermediate frequency amplifier are integrated in the same chip, so that the size of the down-conversion circuit can be reduced, and the miniaturization requirement can be met.

A transportable ultra-wideband frequency spectrum monitoring and direction finding device relates to the technical field of radio direction finding and comprises a plurality of direction finding antenna arrays including a first amplitude comparison direction finding antenna array, a second amplitude comparison direction finding antenna array, a virtual baseline direction finding antenna array, a five-element interferometer direction finding antenna array and a Wattson-Watt direction finding antenna array. The plurality of switch matrix networks are respectively connected with the corresponding direction-finding antenna arrays and are used for switching multiple paths of antenna signals and injecting calibration signals; the plurality of down-conversion board cards are respectively connected with the corresponding switch matrix networks and are used for converting the radio frequency signals of different frequency bands into intermediate frequency signals through multi-stage frequency conversion processing; the digital receiver is connected with the plurality of down-conversion board cards and is used for carrying out direct acquisition and channelization processing on the intermediate frequency signals; and an industrial personal computer. The method and the device are used for solving the problems of limited frequency coverage range, limited lateral azimuth coverage range and limited receiving dynamic range of traditional lateral equipment.

An antenna module may include antennas, RF chains connected to the antennas, a splitter / combiner connected to the RF chains, a mixer configured to upconvert an IF signal input to the antenna module into a transmission RF signal and output the upconverted signal to the splitter / combiner and / or to downconvert a reception RF signal which is a combination of signals from the RF chains provided from the splitter / combiner, a plurality of first couplers connected between the RF chains and the antennas, a second coupler for measuring a magnitude corresponding to a transmission RF signal before split by the splitter / combiner and / or the reception RF signal combined by the splitter / combiner, and a power detector configured to provide a plurality of magnitudes of a plurality of signals from the plurality of first couplers and a magnitude of a signal from the second coupler.