24 results about "Instantaneous frequency measurement" patented technology

The invention relates to the technical field of low-power-consumption electronics, and discloses a low-power-consumption instantaneous frequency measurement system which comprises a radio-frequency signal acquisition module, a signal time-frequency conversion module, a noise floor coding module and the like. The system generates a feature tensor through time-frequency analysis of a radio frequency signal, realizes dynamic threshold fusion in combination with noise floor sparse coding, extracts a multi-scale transient frequency feature by using a pyramid convolutional neural network, dynamically suppresses noise based on a signal-to-noise ratio weight, and reconstructs a real-time spectrum distribution image. The power consumption control module can adjust the ADC sampling rate and the clock frequency of the processing unit according to the signal strength, and the power management unit adopts multi-voltage domain independent power supply. The system solves the problems of frequency measurement precision and power consumption under complex noise, is suitable for the fields of wireless communication and the like, and has the characteristics of high precision, low power consumption, high spectral resolution, visualization and intuition.

The invention discloses a silicon-based integrated device for synchronously measuring microwave frequency and an angle of arrival and a measuring method. The light source is used for emitting light carriers to the input end of the double-parallel Mach-Zehnder photoelectric intensity modulator, and the two radar antennas arranged at intervals receive microwave signals to be measured and send the microwave signals to the double-parallel Mach-Zehnder photoelectric intensity modulator. The double-parallel Mach-Zehnder photoelectric intensity modulator loads a microwave signal to be measured onto an optical carrier to generate two paths of optical carrier microwave signals and sends the two paths of optical carrier microwave signals to the first instantaneous frequency measurement unit and the second instantaneous frequency measurement unit and the arrival angle measurement unit, and rough frequency measurement, fine frequency measurement and arrival angle measurement of the optical carrier microwave signals are carried out respectively. A single structure is adopted, synchronous and efficient measurement of the frequency and the arrival angle of a radar microwave signal is achieved, the detection efficiency is remarkably improved, the technical problem of simultaneous measurement of the microwave frequency and the arrival angle with on-chip integration, high precision, light weight, low power consumption and powerful functions is solved, the practicability of the system is improved, and the application range of the system is widened.

The invention relates to the field of signal frequency detection in microwave photonics, and discloses a broadband instantaneous frequency measurement receiving system based on Brillouin spectrum compression, which utilizes a dual-tone pump optical carrier signal carried on an intensity modulator and an optical filter to generate a single Brillouin pump source regulated and controlled by unknown radio frequency. A stimulated Brillouin structure narrowed by an optical fiber ring cavity and a single-pumping reference source subjected to phase shift beat frequency, a signal in a 45GHz range can be compressed to a bandwidth of 2.5 MHz, and meanwhile, an original signal can be subjected to optical domain down-conversion processing by a reference source signal, so that a low-frequency signal easy to process electronically is obtained; besides, a double-fiber annular cavity design is adopted, the line width of the Brillouin resonant laser is further compressed through mode matching of interference of light waves in the cavity, test precision reduction caused by frequency spectrum compression is made up, the resolution ratio can reach + / -2.2 MHz, and finally the Brillouin broadband instantaneous frequency measurement receiving technology is achieved.

This invention relates to a radio frequency (RF) link and detection device for passive wireless detection equipment, belonging to the field of wireless detection technology. The RF link includes: a tracking local oscillator link, comprising: an instantaneous frequency measurement receiver and a fast frequency hopping synthesizer connected to it; the instantaneous frequency measurement receiver is used to evaluate the frequency of the incoming signal and determine the instantaneous estimated frequency; the fast frequency hopping synthesizer is used to determine the local oscillator frequency based on the instantaneous estimated frequency and perform local oscillator frequency hopping to generate the local oscillator signal; a receiving link is used to mix the incoming signal and the local oscillator signal, down-converting it to an intermediate frequency (IF) signal; and a processing unit connected to the receiving link is used to sample and process the IF signal to track agile wireless detection equipment. Through the above method, the frequency hopping of agile signals can be effectively addressed, avoiding problems such as IF signal distortion, clutter interference, and signal filtering caused by frequency mismatch in traditional ordinary local oscillators.

The present invention discloses a radio frequency signal processing system based on a microwave broadband instantaneous frequency measurement receiver, which specifically relates to the field of electromagnetic frequency measurement of radio frequency signals, including an identification and extraction module, a trajectory reconstruction module, a path switching module, and a prediction and compensation module; the identification and extraction module is used to divide the original radio frequency data stream into equal time segments, and extract the frequency response sequence in each time segment, and mark the time segment that meets the conditions as a frequency masking response segment based on the threshold judgment results of the frequency change speed and the amplitude change slope. By constructing a joint judgment mechanism of the frequency change speed and the amplitude change slope, combined with the frequency jump trend fitting and trajectory connection point reconstruction method, the frequency masking response segment is dynamically identified and its internal frequency evolution path is restored to solve the problem that the frequency blind area caused by geomagnetic disturbance cannot be demodulated.

A monobit analog-digital converter (ADC) system and method are disclosed, the system comprising a front-end signal conditioning system equipped with a programmable attenuator and amplifier for processing analog signals, where the attenuator, which may include a cascade of programmable attenuator cells, is controlled by an attenuation control signal to adjust signal attenuation to cause a signal-to-noise ratio (SNR) in the negative domain, after which an amplifier amplifies the attenuated signal with the suitable SNR, where the amplified signal is then converted to a monobit signal by a monobit ADC, thereby achieving an ADC system that enables conditioning and digitizing of RF signals over a wide range of input signal powers with control over the output spectrum signal power and harmonics to achieve low-power real-time general-purpose broadband blocker detection for adaptive radios and for interference detection, main beam radar signal detection, and instantaneous frequency measurement, among other fields requiring general-purpose blocker identification with low size, weight, power, and cost (SWaP-C).

The present application provides an ultra-wideband instantaneous frequency measurement method and circuit. The method includes: acquiring a radio frequency signal, folding the radio frequency signal at a certain moment based on a local oscillator signal to obtain a target sampling signal; performing a signal type conversion on the target sampling signal within a preset signal processing frequency band to obtain a digital signal; demodulating the digital signal first and then measuring the frequency according to the demodulated signal, so as to restore the instantaneous frequency before the radio frequency signal is folded, complete the analog processing of the digital signal, and no additional analog frequency conversion processing is required. The ultra-wideband instantaneous frequency measurement method provided by the present application breaks through the limitation of the Nyquist sampling theorem, folds the radio frequency signal first to obtain a relevant signal that meets the signal processing of the analog-to-digital converter, can directly use a single analog-to-digital converter to receive and process the ultra-wideband radio frequency signal, and restore the instantaneous frequency value of the relevant radio frequency signal, without other analog processing circuits.

The present invention relates to the field of electronic reconnaissance technology, and particularly to an instantaneous frequency measurement device and method based on an unbalanced dual-arm MZI. In the present invention, the output light of the phase modulator is evenly divided into two paths by a beam splitter. One path of light is connected to a first photodetector after passing through a first MZI, and the other path of light is connected to a second photodetector after passing through a second MZI. The first photodetector and the second photodetector are connected to a signal processing module, wherein the differential delays of the first MZI and the second MZI are τ1 and τ2 respectively. The present invention has the characteristics of few devices and can realize instantaneous frequency measurement of microwave signals without bias voltage control.

A sensor buoy comprising: a buoy casing configured to float on a body of water; an antenna mounted to the buoy casing so as to limit an RF range of view to no more than fifteen kilometers; an instantaneous frequency measurement (IFM) receiver mounted to the buoy casing and communicatively coupled to the antenna; a pulse descriptor word (PDW) generator mounted to the buoy casing and configured to receive an output from the IFM receiver; a processor configured to receive PDWs generated by the PDW generator and to calculate a corresponding pulse repetition interval (PRI); a magnetometer communicatively coupled to the processor; a scheduler communicatively coupled to the processor and configured to control when the sensor buoy transmits information; and a transmitter communicatively coupled to the scheduler and configured to format data from the processor into a correct format and packet structure for transmission.

The invention provides an instantaneous frequency measurement system and method based on a phase modulator, and the system is connected with a vector network analyzer, and comprises a light source module which is used for providing an optical carrier; the modulation module is used for modulating the fed radio frequency microwave signal onto an optical carrier to obtain an optical modulation signal; the wavelength division multiplexing module is used for separating positive and negative first-order sidebands of the optical modulation signal into a first optical modulation signal and a second optical modulation signal; the detection module is used for respectively converting the first light modulation signal and the second light modulation signal into a first electric signal and a second electric signal; the coupling module is used for combining the first electric signal and the second electric signal to form an output electric signal; wherein the vector network analyzer is respectively connected with the modulation module and the coupling module, and the vector network analyzer receives the output electric signal, obtains a power spectrum of the output electric signal and reversely deduces instantaneous frequency information of the radio frequency microwave signal. The system is high in integration level and strong in anti-electromagnetic interference capability, and is suitable for various scenes.

The application discloses a kind of based on three-channel undersampling technology's ultra-wideband instantaneous frequency measurement method, can realize to the multiple signal in ultra-wideband spectrum range is monitored.Radio frequency signal is directly input to three sampling channels after amplification filtering and is sampled, and each road signal sampling rate is different, uses short time window weighting, and utilizes real signal double FFT point method to calculate the frequency that radio frequency frequency is folded into each sampling channel first Nyquist area in short time window, then using sub-band segmentation demodulation method can be calculated out without ambiguity radio frequency frequency.The application can realize the signal in 0~18GHz range is instantaneous frequency measurement in 200ns time, and frequency measurement accuracy is within 1MHz.

A sensor buoy comprising: a buoy casing configured to float on a body of water; an antenna mounted to the buoy casing so as to limit an RF range of view to no more than fifteen kilometers; an instantaneous frequency measurement (IFM) receiver mounted to the buoy casing and communicatively coupled to the antenna; a pulse descriptor word (PDW) generator mounted to the buoy casing and configured to receive an output from the IFM receiver; a processor configured to receive PDWs generated by the PDW generator and to calculate a corresponding pulse repetition interval (PRI); a magnetometer communicatively coupled to the processor; a scheduler communicatively coupled to the processor and configured to control when the sensor buoy transmits information; and a transmitter communicatively coupled to the scheduler and configured to format data from the processor into a correct format and packet structure for transmission.

A monobit analog-digital converter (ADC) system and method are disclosed, the system comprising a front-end signal conditioning system equipped with a programmable attenuator and amplifier for processing analog signals, where the attenuator, which may include a cascade of programmable attenuator cells, is controlled by an attenuation control signal to adjust signal attenuation to cause a signal-to-noise ratio (SNR) in the negative domain, after which an amplifier amplifies the attenuated signal with the suitable SNR, where the amplified signal is then converted to a monobit signal by a monobit ADC, thereby achieving an ADC system that enables conditioning and digitizing of RF signals over a wide range of input signal powers with control over the output spectrum signal power and harmonics to achieve low-power real-time general-purpose broadband blocker detection for adaptive radios and for interference detection, main beam radar signal detection, and instantaneous frequency measurement, among other fields requiring general-purpose blocker identification with low size, weight, power, and cost (SWaP-C).

The invention relates to the field of integrated antennas, in particular to an ultra-wide frequency band detection and calibration integrated antenna feeder system. The system comprises an omnidirectional monitoring antenna, a transmitting antenna array and a direction-finding antenna array covering four azimuth planes of 360 degrees, a positioning module, a gyroscope, a calibration module, a digital processing module, an instantaneous frequency measurement receiver, a general monitoring receiver, a direction-finding receiver and a T assembly. The omnidirectional monitoring antenna is used for monitoring and receiving electromagnetic signals in 360-degree directions; the transmitting antenna array of the four azimuth planes is connected with the T component and interferes with a set signal according to the direction-finding azimuth, and each array plane of the direction-finding antenna array of the four azimuth planes consists of four pairs of antennas and is used for carrying out interferometer direction finding on the set signal; the positioning module is used for receiving a positioning signal and providing positioning information and a time reference for the system; the gyroscope is used for carrying out self-positioning on the system attitude and providing angle deflection angle information of the equipment relative to the true north for the system. The method is suitable for the electronic countermeasure system.

The utility model relates to the technical field of signal receiving and processing of electronic warfare detection equipment, in particular to an ultra-high-speed sampling frequency measurement processing board for a single-bit receiver, which comprises a frequency measurement processing board body, and a high-speed ADC (analog-to-digital converter) module, an FPGA (field programmable gate array) module, a low-speed ADC module, a power module and an interface module are integrated on the frequency measurement processing board body. The high-speed ADC module is directly connected with the FPGA module, the FPGA module receives digital signals output by the high-speed ADC module, the low-speed ADC module is used for converting linear video amplitude output by the SDLVA into digital signals and outputting the digital signals to the FPGA module, and the processing board integrates the high-speed ADC module, the FPGA module, the low-speed ADC module, a power supply module and an interface module. The processing board can directly sample and quantify 2-18GHz radio frequency signals, realizes pipelined instantaneous frequency measurement through the FPGA, and accurately outputs frequency and amplitude information of the signals.

The present application relates to the field of integrated antenna, in particular to a kind of ultra-wideband reconnaissance jamming school integrated antenna feed system.It contains omnidirectional monitoring antenna, four azimuth plane transmitting antenna array and direction-finding antenna array covering 360 ° azimuth, positioning module, gyroscope, calibration module, digital processing module, instantaneous frequency measurement receiver, general monitoring receiver, direction-finding receiver and T component;Omnidirectional monitoring antenna is used to monitor and receive 360 ° azimuth electromagnetic signal;Four azimuth plane transmitting antenna array is connected with T component, and according to the direction-finding azimuth, the signal set is interfered, and four azimuth plane direction-finding antenna array is composed of 4 pairs of antennas, and is used for interferometer direction-finding to the signal set;Positioning module is used to receive positioning signal, and provides positioning information and time reference for system;Gyroscope is used for self-positioning to system attitude, and provides the angle deflection angle information of equipment relative to north for system.The present application is suitable for electronic countermeasure system.

The present invention discloses a silicon-based integrated device and measurement method for synchronous measurement of microwave frequency and arrival angle. A light source is used to emit an optical carrier to the input end of a dual-parallel Mach-Zehnder optoelectronic intensity modulator. Two radar antennas arranged at intervals receive the microwave signal to be measured and send it to the dual-parallel Mach-Zehnder optoelectronic intensity modulator. The dual-parallel Mach-Zehnder optoelectronic intensity modulator loads the microwave signal to be measured onto the optical carrier to generate two optical microwave signals and sends them to a first and second instantaneous frequency measurement unit and an arrival angle measurement unit, respectively, to perform rough and fine frequency measurement and arrival angle measurement of the optical microwave signal. The present invention adopts a single structure to achieve synchronous and efficient measurement of radar microwave signal frequency and arrival angle, significantly improving detection efficiency, solving the technical problems of on-chip integration, high precision, lightweight, low power consumption, and powerful simultaneous measurement of microwave frequency and arrival angle, and enhancing the practicality and applicability of the system.

The application relates to a multi-channel ultra-wideband undersampling instantaneous frequency measurement method, belonging to the technical field of wideband digital radars, and solving the problem of spectrum overlap of multiple signals; for a scheme of multiple channels with different time delays, phase frequency measurement is combined with the remainder theorem to demodulate the frequency of an input signal; for signals near f s / 2, phase frequency measurement is carried out through the time delay difference between different channels to solve the frequency band in a targeted manner; for signals near f s / 2, multi-rate sampling is realized through a time-sharing sampling method, threshold discrimination and parameter matching are carried out on the FFT frequency measurement result through the remainder theorem, and finally, the PDW signal is demodulated, the method does not need to provide a high-speed pseudo-random sequence, has hardware realizability, has the characteristics of small size, no need of channelization, low algorithm implementation complexity, strong robustness and strong demodulation capability compared with the prior art, and can realize high-precision undersampling frequency estimation of radar signals under the index of 0 to 18G instantaneous bandwidth.

The invention discloses a radio frequency signal processing system based on a microwave broadband instantaneous frequency measurement receiver, particularly relates to the field of electromagnetic frequency measurement of radio frequency signals, and comprises an identification extraction module, a track reconstruction module, a path switching module and a prediction compensation module. The recognition and extraction module is used for dividing an original radio frequency data stream into equal-length time slices, extracting a frequency response sequence in each time slice, and marking the time slice meeting the condition as a frequency shielding response section according to a threshold judgment result of a frequency change speed and an amplitude change slope. By constructing a combined judgment mechanism of the frequency change speed and the amplitude change slope and combining a frequency hopping trend fitting and track connection point reconstruction method, a frequency shielding response section is dynamically identified, and an internal frequency evolution path is recovered, so that the problem that a frequency blind area caused by geomagnetic disturbance cannot be demodulated is solved.

The present invention discloses a system for intercepting and direction finding of discontinuous ultra-wideband pulses, which relates to the field of electronic reconnaissance technology. The system includes an antenna array, a radio frequency routing and distribution module, an instantaneous frequency measurement module, a multi-channel down-conversion module and a multi-channel acquisition and processing module. Among them, the antenna array adopts an interferometer antenna array composed of multi-element planar spiral antennas. The instantaneous frequency measurement module includes a microwave channel unit, a high-speed ADC unit, a slow-speed ADC unit and an FPGA unit, and can realize a 5ns fast-response SDLVA video detection + high-speed 1-bit frequency measurement system to intercept discontinuous ultra-wideband pulses and extract relevant parameters. Furthermore, after fusing the pulse description word information with the direction finding result, the function of intercepting and direction finding of discontinuous ultra-wideband pulses can be formed, solving the problems of low intercept success probability of the existing intercepting and direction finding system for discontinuous ultra-wideband pulses and difficult signal warning recognition and azimuth measurement even if intercepted.

The invention relates to a radio frequency link for passive wireless detection equipment and the detection equipment, and belongs to the technical field of wireless detection. The radio frequency link comprises a tracking local oscillator link which comprises an instantaneous frequency measurement receiver and a fast frequency hopping frequency synthesizer which are connected; the instantaneous frequency measurement receiver is used for carrying out frequency evaluation on an incoming wave signal and determining an instantaneous estimation frequency, and the fast frequency hopping frequency synthesizer is used for determining a local oscillation frequency based on the instantaneous estimation frequency, carrying out local oscillation frequency hopping and generating a local oscillation signal; the receiving link is used for performing frequency mixing and down-conversion on the incoming wave signal and the local oscillation signal to obtain an intermediate frequency signal; a processing unit; and the sampling link is connected with the receiving link and is used for sampling the intermediate frequency signal so as to track the agile wireless detection equipment. By means of the mode, frequency hopping of agile signals can be effectively coped, and the problems of intermediate frequency signal distortion, clutter interference, signal filtering and the like caused by frequency mismatching of a traditional common local oscillator are solved.

The present invention relates to the field of low-power electronic technology, and discloses a low-power instantaneous frequency measurement system, which includes a radio frequency signal acquisition module, a signal time-frequency conversion module, a noise base coding module, etc. The system generates a feature tensor by performing time-frequency analysis on the radio frequency signal, realizes dynamic threshold fusion in combination with noise base sparse coding, extracts multi-scale transient frequency features using a pyramid convolutional neural network, dynamically suppresses noise based on the signal-to-noise ratio weight, and reconstructs a real-time spectrum distribution image. The power consumption control module can adjust the ADC sampling rate and the processing unit clock frequency according to the signal strength, and the power management unit adopts multiple voltage domains for independent power supply. The system solves the problems of frequency measurement accuracy and power consumption under complex noise, is applicable to fields such as wireless communications, and has the characteristics of high precision, low power consumption, high spectrum resolution, and intuitive visualization.

This invention discloses an ultra-wideband, high-precision instantaneous frequency measurement circuit and method, belonging to the field of frequency measurement technology. It includes a power divider group, multiple frequency measurement channels, an analog switch group, an SP3T switch, a direct digital frequency synthesizer (DDS), and an FPGA. The input RF signal is divided into four channels by the power divider group, corresponding to four frequency measurement channels. Each frequency measurement channel corresponds to a different frequency range, and the channels operate in parallel. Each channel signal is output as an LVTTL level to the FPGA after passing through a detector and comparator. The FPGA determines the frequency range based on the level combination and controls the analog switch and SP3T to select the corresponding channel. The frequency of the signal generated by the DDS is measured by the FPGA, and the input RF signal frequency is calculated inversely based on the division ratio and frequency control word. This invention achieves DC-20GHz ultra-wideband frequency measurement. The measurement speed depends on the DDS frequency switching speed. After the measurement is completed, the power to the divider is turned off to eliminate spurious interference. The circuit structure is simple and low-cost.