421 results about "Electronic countermeasure" patented technology

A tactical radio includes a radio frequency (RF) processing module having a receiving component path and a transmitting component path. A signal processing module coupled to the RF processing module includes a jammer detection stage for identifying a type of jamming signal on a channel over which communications signals are received simultaneously. A jammer model stage in the signal processing module produces a waveform model for the jamming signal, and a channel model stage replicates propagation conditions on the channel and produces a corresponding cancellation signal. The cancellation signal is coupled at such a level into the receiving component path so as to cancel the jamming signal from received communications signals at the front end of the radio. Any residual jamming signals may then be removed by a secondary jamming cancellation stage operating at baseband.

The invention discloses a periodic amplitude control-based phased-array antenna system. The periodic amplitude control-based phased-array antenna system comprises a plurality of phased-array antenna unit passages, a combiner, a power divider, a frequency converter unit and a medium frequency band pass filter unit, wherein each phased-array antenna unit passage comprises an antenna, a first radio frequency band pass filter, a duplexer, a variable gain amplifier unit, a second radio frequency band pass filter and an amplifier control unit; and the amplifier control unit periodically controls the gain of the variable gain amplifier unit. The invention also discloses a wave beam control method of the periodic amplitude control-based phased-array antenna system. By periodically controlling the amplitude of a transmitted/received radio frequency signal, combined control over the amplitude and the phase of the phased-array antenna system is realized, and directional diagram synthesis and adaptive wave beam formation of a phased-array antenna array can be realized without using a phase shift device; and the periodic amplitude control-based phased-array antenna system can be widely applied to systems requiring flexible wave beam control such as phased-array radar and electronic countermeasure.

A system deploys electronic countermeasures against unmanned aerial vehicles (UAVs) that are determined to be a threat. A signal detector detects radio signals communicated between a remote control unit and UAV. A feature extractor extracts signal features from the detected radio signals, and a classifier determines whether the detected radio signals correspond to a known or unknown radio protocol. A threat analyzer determines if a detected UAV is a threat based on at least one of remote-sensing data and classification(s) of the detected radio signals. When a UAV system employs an unknown radio protocol, a mitigation engine synthesizes an exploit based on corresponding extracted signal features. A response analyzer detects a response from the UAV system when an exploit is activated and mayadapt the exploit based on the response. In some cases, the exploits can be configured against a UAV in autopilot mode.

A flight-operable, truly modular aircraft has an aircraft core to which one or more of outer wings members, fuselage, cockpit, leading and trailing edge couplings, and empennage and tail sections can be removably coupled and/or replaced during the operating life span of the aircraft. In preferred embodiments the aircraft core houses the propulsive engines, avionics, at least 80% of the fuel, and all of the landing gear. The aircraft core is preferably constructed with curved forward and aft composite spars, that transfer loads across the center section, while accommodating a mid-wing configuration. The aircraft core preferably has a large central cavity dimensioned to interchangeably carry an ordnance launcher, a surveillance payload, electronic countermeasures, and other types of cargo. Contemplated aircraft can be quite large, for example having a wing span of at least 80 ft.

A flight-operable, truly modular aircraft has an aircraft core to which one or more of outer wings members, fuselage, cockpit, leading and trailing edge couplings, and empennage and tail sections can be removably coupled and/or replaced during the operating life span of the aircraft. In preferred embodiments the aircraft core houses the propulsive engines, avionics, at least 80% of the fuel, and all of the landing gear. The aircraft core is preferably constructed with curved forward and aft composite spars, that couple to outer wing sections and possibly other sections using hardpoints. The aircraft core preferably has a large central cavity dimensioned to interchangeably carry an ordnance launcher, a surveillance payload, electronic countermeasures, and other types of cargo. Contemplated aircraft can be quite large, for example having a wing span of at least 80 ft.

A system is provided that has an ECM (electronic counter measures) system and a transponder monitor connected to or forming part of the ECM system. The system monitors for a transponder signal from a remote transponder. The system determines information, such as transponder location, based on the transponder signal and makes use of the information in the ECM system and/or the system extracts encoded information contained in the transponder signal, such as information about a transponder owner, such as status of consumables, medical status. The ECM system may have a reactive jammer that is used both for a reactive jamming function, and as the transponder monitor function.

The invention provides a THz wave radiation source with an oval groove grating structure. The oval groove grating with periodicity is adopted as a beam-wave interaction structure of the radiation source. When an electron beam passes through the structure at a certain speed, the electron beam and surface slow waves interact to be clustered and generate an electron beam cluster, then Smith-Purcell coherent radiation is stimulated, radiation is collected through a flat plate or a curved mirror (metal or medium) to generate tunable, compact and high-power THz waves, and therefore the THz wave radiation source can be easily applied to communication, radars, electronic countermeasures, electromagnetic weapons, astronomy, medical imaging, nondestructive detection, safety inspection and other aspects.

A device and method for estimating the operational effectiveness, status, and protection range of an electronic countermeasures system in real time or near real time are provided. The device and method calculate a predicted ECM power at a given location using a propagation and scenario model. Then a measured ECM power at the given location is used to determine a correction value equal to the difference between the calculated and measured ECM powers. The correction value and the propagation model are then used with a heuristic method to refine estimates of propagation and scenario parameters. The refined parameter set is used to produce a refined prediction of ECM power, which is used to create a refined correction factor. The refined correction factor is used to determine predicted ECM powers at a plurality of locations in an area around the device to determine a boundary of protection.

The invention belongs to the technical field of radar signal sorting in electronic countermeasure, and discloses a radar signal sorting method and system in a high pulse density environment, and the method comprises the steps: dividing received radar pulse description words according to a pulse arrival angle to acquire a plurality of groups of pulse sequences from different directions; inputting the pulse frequency domain parameter and the pulse width of each group of pulse sequence into a cascade structure self-organizing mapping neural network to obtain a primary sorting result; using an improved sequence difference histogram algorithm for the primary sorting result to acquire a main sorting result; and traversing the combination condition of the main sorting result, inputting the pulsefrequency domain parameter, the pulse width and the pulse arrival time into a long-short-term memory network to carry out repetition frequency identification, and combining to obtain the repetition frequency group-change radar. According to the invention, common radar signals (repetition frequency fixing, repetition frequency staggering, repetition frequency jittering, repetition frequency slidingchange and repetition frequency group change) in a high pulse density environment can be effectively realized; and real-time sorting of radar signals in an actual electromagnetic environment can be realized.

The invention discloses a phase interferometer based on a broadband conformal antenna array and a parameter estimation method thereof. The phase interferometer is characterized by comprising a five-unit Vivladi conformal antenna array, a streamline ceramic antenna housing and a metal connecting ring on the antenna housing, wherein the number N of antenna units of the five-unit Vivladi conformal antenna array is 5, each unit is shaped on the surface of the antenna housing, the antenna units and the antenna housing are conformal, and the units are arranged circumferentially to form a ring array. The phase interferometer is suitable for a missile-borne passive direction finding system, and the estimation algorithm for electromagnetic parameters of radiation source signals is also applicable in relevant fields of electronic reconnaissance, electronic countermeasure and the like and has more comprehensive parameter measurement performance and platform adaptability.

The invention relates to a chaotic signal source with adjustable dynamic amplitude linearity and a system with identical dynamic characteristics, comprising an inverse proportion circuit, a first integrating circuit, a second integrating circuit and a third integrating circuit, wherein the output ends of a third operational amplifier, a second operational amplifier and a first operational amplifier sequentially output three state variables (x, y, z) of the chaotic signal source; when the chaotic signal source works, the dynamic amplitudes of the three state variables (x, y, z) are linearly adjusted by adjusting the output voltage of a DC power supply, and the three state variables (x, y, z) are enabled to have the identical dynamic characteristics. Because the chaotic signal source has adjustable amplitude and frequency spectrums of different frequency ranges and the like under the precondition without changing the dynamic characteristics of an output signal, the chaotic signal source is indicated to have extensive application prospect and important application value in the high technology fields of chaotic radars, secret communication, electronic countermeasure, and the like.

The invention provides an ultra wide band antenna with trap characteristic, which comprises a medium substrate, a radiating unit, a coplanar waveguide feed signal zone line and a coplanar waveguide ground plane, wherein the coplanar waveguide feed zone line is directly connected with the radiating unit, and the coplanar waveguide ground plane surrounds the radiating unit and the coplanar waveguide feed signal zone line. The antenna has favorable wide band characteristic and omnidirectional radiation characteristic, and the trap characteristic of the antenna can avoid interfering communications of wireless local area networks. The antenna has the advantages of simple and compact design, small size, convenient processing and low cost. The invention can be used for electronic reconnaissance and electronic countermeasure, terminal receiving equipment for tracking, electromagnetic protection and ultra wide band wireless communications, and the like.

The invention belongs to the technical field of radar electronic countermeasures, and discloses a method for detecting, distinguishing and suppressing cross-eye jamming by a single-pulse radar. The method is characterized in that two types of angle measuring methods are started to carry out angle measurement again when the single-pulse radar is subjected to the cross-eye jamming and loses a target, whether the cross-eye jamming exists or not is detected through comparing the difference of measured angles acquired by the two types of angle measurements methods, and the cross-eye jamming is suppressed through a method of tracking a jamming source if the jamming exists. The method disclosed by the invention is mainly applied to detecting and suppressing the cross-eye jamming, and influences imposed on the direction finding performance of the single-pulse angle tracking radar by the jamming are eliminated. The method can also be applied to various single-pulse radars or signal detecting, recognizing and tracking devices, thereby quickly recognizing the cross-eye jamming, improving a jamming recognition ability of the system, and effectively resisting the cross-eye jamming.

The invention discloses a multi-frequency high-precision microwave photon frequency measuring scheme based on stimulated brillouin effect. The multi-frequency high-precision microwave photon frequency measuring scheme comprises a single-wavelength laser device (101), a dual-drive mach-zehnder modulator (102), a mach-zehnder modulator (103), a optical isolator (105), a dispersion-shift optical fiber (106), an optical circulator (107), a photoelectric detector (108), an electric processing unit (109), a reference microwave source (104). Compared with other microwave photo frequency measuring schemes, double mapping relationship which are dynamic frequency-power mapping and frequency-phase mapping in the brillouin effect are respectively utilized, the multi-frequency instant measuring and the single-frequency error measuring are combined, so that the multi-frequency high-precision microwave photo frequency measuring is realized. The multi-frequency high-precision microwave photon frequency measuring scheme can be applied to the electronic countermeasure and the microwave detecting field.

The invention belongs to the technical field of electronic countermeasures, and particularly relates to a radar signal sorting method based on combination of an SDIF and a PRI transformation method. With the adoption of the method, the search effect is faster and more obvious. The method comprises the following steps that radar signals are pre-grouped; an arrival time difference histogram is established for pre-sorted radar groups by using the SDIF; the radar signals are quickly searched and extracted according to the time domain characteristics of a radar signal model; a first-level difference histogram is established to quickly analyze staggering signals; whether complex type radar signal residues exist or not is judged; and the sorting result of each module is inquired. The beneficial effects of the method are that pre-sorting and main sorting are combined, the SDIF and the PRI transformation method are combined to act as main sorting, the SDIF part performs quick and effective sorting on the conventional signals, the staggering signals, the inter-pulse frequency agility and the pulse group frequency agility signals in the complex radar electromagnetic environment, the PRI transformation method part sorts the remaining jitter signals, and each part of the algorithms performs its own functions and is connected to form an effective and quick comprehensive sorting algorithm.

The invention relates to a timing control circuit of a pulse power supply. The timing control circuit comprises a DC/DC (Direct Current) converter 1, a DC/DC converter 2, a power-on detection circuit, a delay circuit, a power-down detection circuit, switching current and a drive circuit. The power-on timing problems of GaAs devices and the like are solved by fewer components. The power-down timing circuit solves the damage problems of the GaAs devices and the like caused by timing abnormity due to output power-down. The power-down timing circuit is combined with the delay circuit, so that the output overcurrent or short-circuit protection problems of positive voltage are simultaneously solved. The timing control circuit provided by the invention can be widely applied to electronic circuits which need to meet positive and negative power supply timing in the fields of communications, radar, aviation, electronic countermeasure and the like.

The invention discloses a three-frequency medium resonant antenna with a function of coaxial feed. A medium resonant cavity is the resonant cavity which is made from a high dielectric constant material, the medium resonant cavity is arranged on a ground potential surface, the upper part at the center in the medium resonant cavity is embedded with an air resonant cavity, a filling medium in the air resonant cavity is air, a metal paster is arranged at the center of the upper ends of the medium resonant cavity and the air resonant cavity, a coaxial feed source comprises a probe needle, a mediumlayer and an outer conductor, the probe needle penetrates through the ground potential surface from the lower part of the ground potential surface to enter into the medium resonant cavity, the mediumlayer is arranged between the ground potential surface and the probe needle, and the medium layer under the ground potential surface is externally provided with the outer conductor. The medium resonant cavity, the air resonant cavity and the metal paster are integrated with one another to offer three different frequency points, so that the three-frequency medium resonant antenna has the characteristics of being small in volume and wide in frequency band, thereby being capable of playing an important role in satellite communication and military electronic countermeasure uniquely.

An algorithmic approaches that can be implemented in software/firmware/hardware that filters out stable PRI patterns detected within a system that is prosecuting against radar based transmissions are disclosed. The algorithms allow downstream computing assets to concentrate their limited resources on the more complex emitter PRI pattern types. Thus, a portion (e.g., stable signals) of the pulse deinterleave and PRI identification problem is solved without requiring the more computationally expensive processing. The disclosed algorithms can be employed, for example, in electronic support measures (ESM) systems, electronic intelligence (ELINT) systems, and/or a electronic countermeasures (ECM) systems. The algorithms employ linear detection, linear regression, or a combination of linear detection and linear regression, thereby providing a “dual voting” scheme that decreases the occurrence of false positives. Other algorithmic approaches can be used as well in a multi-voting scheme that considers PRI estimates from distinct analysis types.

The invention, which belongs to the technical field of electronic countermeasures, in particular relates to a time-difference-information-based passive multi-station multi-target direction-finding cross-positioning method. According to the method, on the basis of a multi-radiation-source data association algorithm, observation data from multiple observation stations are associated to obtain a costmatrix C(p,q); and then a coordinate of a target is estimated by using an aggregation hierarchy clustering algorithm based on the obtained cost matrix C(p,q). The method has the following beneficialeffects: association of data from multiple stations is completed accurately and the location of the target is estimated finally and accurately. The method is simple and has the good effect.

The invention provides an ultra broadband antenna of an integrated filter, which comprises a medium substrate, a microstrip feeder structure of a radiating unit arranged on one side of the medium substrate, the other side of the medium substrate is partially grounded, the radiating unit is provided with a split-ring resonator (SRR), and a microstrip line is directly connected to the radiating unit. The antenna relates to the invention has excellent broadband property and good omnidirectional radiation property, and the antenna is integrated with a filter with a complementary split-ring resonator (CSRR), so that the influence between the communication of local area network and ultra broadband communication system of the antenna can be prevented. The antenna provided by the invention has the advantages that the design is simple and compact, the volume is small, the process is convenient and the cost is low. The antenna can be applied to electronic reconnaissance device and electronic countermeasure device and the like.

The invention belongs to the field of electronic countermeasure and communication technologies and discloses a parameter estimation method for frequency hopping signals in frequency hopping non-cooperative communications. The method comprises the steps of performing time-frequency analysis on a received signal to obtain a time-frequency diagram thereof, and taking the maximum frequency value in the time domain from the time-frequency diagram to obtain a time-frequency ridge line; performing first-order difference processing on the time-frequency ridge line to obtain a frequency hopping momentdiagram; selecting a plurality of peak points in the first-order differential frequency hopping moment diagram to fit a straight line, and estimating the hopping speed and hopping time by using a formula according to the straight slope; decomposing the frequency hopping signal into a number of single-frequency signals according to the estimated hop speed and hop time, performing FFT preprocessing,and estimate the frequency of the single-frequency signals in each time slot using Zoom-FFT, and obtaining a frequency hopping pattern after all the frequencies in the hopping period are estimated. The parameter estimation method in the invention has good performance in the estimation of hopping speed and hopping time, and obviously improves the estimation performance of the frequency hopping pattern at a low signal-to-noise ratio as compared with the LS-Kay method.

The invention belongs to the technical field of high-power microwave transmitting antennas, and provides a high-power microwave phased-array antenna with reconfigurable leftward and rightward rotation circular polarization, wherein the high-power microwave transmitting antenna also has two-dimensional phase scanning and polarization reconfiguration functions. According to the high-power microwave phased-array antenna, reconfiguration leftward and rightward rotation circular polarization patch antenna units form an array, so angular phase rotation of array elements and polarization configuration can be achieved by means of one motor, and the array has the beam two-dimensional phase scanning function and the on-line real-time polarization reconfiguration function simultaneously. The high-power microwave phased-array antenna can be widely used for the fields of high-power microwave transmitting, high-power microwave transmitting, electronic countermeasure, phase control radar and the like.

The invention provides a broadband linear frequency modulation signal direction finding system based on time modulation. An antenna array module is connected with a radio frequency switch module, theradio frequency switch module is connected with a radio frequency receiving channel module, the radio frequency receiving channel module is connected with a time-frequency signal processing module, the time-frequency signal processing module is connected with an output display module, and a digital control module is connected with the radio frequency switch module and the time-frequency signal processing module at the same time. The invention also provides a broadband linear frequency modulation signal direction finding method based on time modulation. The method aims to solve the direction finding problem of broadband linear frequency modulation signals in application of communication, radars and the like. Broadband incoming signals are filtered by the high-speed switching radio-frequencyswitch module and divided into a plurality of sub-band signals in a time domain, and the measurement of the incoming wave direction is realized by analyzing the time-frequency spectrum of each sub-band signal. The method has the advantages of being low in cost, simple in structure and low in algorithm complexity, and can be widely applied to the fields of broadband communication, electronic countermeasure and the like.

The invention discloses an instantaneous frequency measurement method based on the adaptive filtration theory. The adaptive filtering algorithm is utilized to decompose a nonstationary multi-frequency component signal into a plurality of progressive single-frequency signals to be measured, thus solving the analyzing problem of the multi-frequency component signal. The Hilbert transformation is adopted to perform instantaneous frequency measurement to the progressive single-frequency signals, thus complete and accurate instantaneous physical quantity of the nonstationary multi-frequency component signal can be obtained, the time-frequency distribution of the nonstationary signal can be further obtained and the requirements of instantaneous frequency measurement in the fields of military communication and electronic countermeasure can be satisfied.