Method and device for recognizing airplane destruction

FIELD: security facilities.

SUBSTANCE: invention relates to systems for detecting objects by reflecting radio waves from the surface of said objects and can be used in radio location to recognize the destruction of an aircraft. Technical result is achieved by the fact that in the method for recognizing the destruction of an aircraft, which consists in emitting an electromagnetic energy in the direction of an airplane, receiving signals reflected from the aircraft, obtaining a spectrum of the reflected signal, carrying out a narrow-band filtering of the Doppler frequency components, additionally determining the presence of the Doppler frequency at a frequency caused by movement with a speed close to the velocity of the shock front, ensuring its reproduction, indicating and signaling on the presence of this signal. Device implementing the method comprises a series-connected antenna and a radar, a filter tuned to the Doppler frequency caused by movement at a speed close to the velocity of the shock front, a speaker, a detector, a threshold device and an indication circuit, the filter input being connected to the output of the radar, the output of the filter is connected to the inputs of the speaker and detector, whose output through the threshold device is connected to the indication circuit.

EFFECT: achieved technical result – provision of the possibility of recognizing the destruction of an aircraft.

2 cl, 1 dwg

 



 

Same patents:

FIELD: physics, navigation.

SUBSTANCE: invention relates to radio electronics, particularly, to configuration of radar and hydro acoustic data processing system intended for automatic moving target tracking. Invention consists in smoothing the tracked target coordinates with the help of ripple filters of different lag. In case the number of processing cycles calculated from the instant of detection of target "primary" mark does not exceed preset magnitude, then, low-lag filter is used. On the contrary, if it exceeds said preset magnitude, higher-lag filter is used.

EFFECT: reduced amount of target tracking errors at smaller number of contacts with target.

3 cl, 2 dwg

FIELD: radio engineering, communication.

SUBSTANCE: decision on detection, tracking or reset of trajectory from tracking is accepted using sequential criterion according to which to each assumed or tracked trajectory some conditional weight Wi is assigned which is compared with two thresholds H1 and H2 defined by pre-set probabilities of correct detection of target trajectory and false alarm. The conditional weight Wi at each processing cycle is changed, increasing it by the value of the positive increment dwi+. The decision on trajectory detection is made if, the condition Wi>H2 is fair, if Wi<H1, then the decision is made of trajectory reset from tracking, if H1≤Wi≤H2 the tests are continued. The named technical result is achieved due to that at each processing cycle the difference between the measured value of the coordinate of detected mark of a target xi and its extrapolated to the current processing cycle by the value Xei, and the positive increment dwi+ is increased Gi times, determined in respective way.

EFFECT: decrease of probability of formation of false trajectories.

4 cl, 1 dwg

FIELD: physics.

SUBSTANCE: invention relates to imaging systems and can be used to detect concealed objects. Electrical properties of concealed objects, for example permittivity, can be obtained from information on incident, reflected and transmitted electromagnetic waves in an imaging system. The imaging system comprises a transmitter for directing radiation into the inspected volume, a receiver for receiving scattered radiation from said volume, a reflecting array for focusing an incident radiation beam, a processor for processing scattered radiation for imaging in accordance with the amplitude and phase of the received radiation and a display. The difference in the amplitude and phase between the object and the reflecting space is used to estimate relative permittivity and therefore serves to classify objects using a relative permittivity database of substances.

EFFECT: detecting concealed objects.

15 cl, 4 dwg

FIELD: transport.

SUBSTANCE: machine (2) inner space control system (20) comprises radar (26) transmitting radar radiation (28) into inner space (6), radar receiver (34) to receive radar radiation reflected into said space (6) and outputting it as a received signal (36), control and processing unit (38) to define actual signature (40a) from received signal (36) and to compare it with stored preset signature (40b) of flawless machine (2) and unit (42) to output signal (46, 52a,b) of fault at departure of actual signature (40a) from preset signature (40b) by permissible tolerance (44).

EFFECT: perfected control.

7 cl, 1 dwg

FIELD: physics.

SUBSTANCE: method comprises steps of: calculating a first reference quantity which characterises a Poisson distribution assumed for characteristics that the pixels in the Synthetic Aperture Radar (SAR) image would have if the sea area were free of targets. The method further comprises steps of: selecting pixels in the Synthetic Aperture Radar (SAR) image, calculating a real quantity which characterises a real statistical distribution of characteristics of the selected pixels, and detecting a target in the sea area based on the calculated first reference and real quantities. The selected pixels are in the same sub-image of the Synthetic Aperture Radar (SAR) image, and detecting involves detecting a target in a sea sub-area of the sea area, the sea sub-area being represented by the sub-image.

EFFECT: high accuracy of target detection.

4 cl, 13 dwg

FIELD: physics.

SUBSTANCE: apparatus has a transmitting and a receiving unit connected a recorder, a support-swivelling block on which is mounted a two-dimensional flat square equidistant array of identical and identically directed radar objects, placed at the nodes of a two-dimensional grid with square cells with spacing where λ is the wavelength, wherein one of the diagonals, the normal to the plane of the array, the normal to the plane of the front of the electromagnetic wave emitted by the transmitting unit and the normal to the plane of the front of the electromagnetic wave reflected from that array lie in a single plane.

EFFECT: high accuracy of measuring ultra-small values of effective scattering area of radar objects located in a confined measuring zone.

5 dwg

FIELD: physics.

SUBSTANCE: disclosed device has a synchroniser, a modulator, a microwave oscillator, an antenna switch, a receiver, a range measuring system, a resolver, an antenna, an antenna control system, a velocity measuring system, three analogue-to-digital converters, memory, a fast Fourier transformation computer, a classification unit, designed and connected to each other in a certain way.

EFFECT: high quality of classifying location objects according to the structure of a vibration map owing to further consideration of phase information of reflected signals, owing to exclusion of components arising from direct reflection from the body of an object and presence of scanning frequencies, and owing to averaging of negative spectral components of the turbo-prop effect.

1 dwg

FIELD: radar-location.

SUBSTANCE: proposed method of measuring local effective reflective surfaces of objects relates to radar-location. The method is based on irradiating radar-location objects in free space with a series of ultra-short pulses. The measured time dependence of the probe signal in the point of irradiation of the object at a distance R from antennae is approximated using a wavelet and numerical values of its parametres w and z are found. Through Fourier transform of the measured time dependence of the probe signal, the energy frequency spectrum (EFS) of the probing field is determined. The time signal reflected from the object is then recorded, and based on the found approximate wavelet energy wavelet-spectra of coefficients of wavelet-transformation of the reflected signal are calculated. On the wavelet spectrogram of the energy spectrum in coordinates of scale and shift parametres, the values of scale and shift parametres of the corresponding maximum reflected energy are calculated, arising from the j-th local scattering centre - "bright point". The local energy spectrum of coefficients of wavelet-transformation is calculated. Frequency is determined as the average wavelet frequency with parametres w and z and scale and shift parametres of the analysed "bright point". The frequency range of the analysed local energy frequency spectrum is determined and the local energy frequency spectrum of the j-th "bright point" is determined. From the measurements carried out, the local effective reflective surface of the analysed local scattering centre of the object is determined.

EFFECT: fast determination of local effective reflective surfaces of radar-location objects with increased accuracy due to time localisation of spectral components of the reflected signal.

17 dwg

FIELD: physics; radio technology.

SUBSTANCE: invention pertains to radio technology and can be used in panoramic receivers of jamming stations, radio direction-finders and similar devices for detecting ground based sources of radio frequency emission, functioning under conditions of interference of unknown intensity. The technical outcome is the reduction of the survey time of the analysed frequency band at a given certainty of opening a radio frequency environment. A dual-threshold scheme for decision taking is realised with automatic switching on the results of controlling the ratio of the power of the signal/noise in the resolution cell. The detector consists of a receiver antenna (1), linear receive path (2), quartz phase detectors (3.1,3.2), reference frequency generator (4), 90° phase shifting unit (5), integrators (6.1,6.2,6.3), quadratic detectors (7.1,7.2,7.3), adder (8), threshold device (17), unit for calculating coefficient K of increasing the analysis time of one resolution cell (14), unit for generating the first and second thresholds (16), switches (9.1,9.2,9.3), comparators (10.1,10.2), accumulators (11.1,11.2), OR elements (13.1,13.2), device for measuring the ratio of the power of signal/noise (12), subtracting unit (15).

EFFECT: shorter time of surveying the analysed frequency band at a given certainty of opening the radio frequency environment.

2 dwg

FIELD: radar engineering.

SUBSTANCE: proposed device designed for identifying objects incorporating revolving components (helicopters, propeller-driven airplanes) by means of acquisition radars at relatively low repetition frequency of sounding pulses (about 2000 Hz) and low time of contact with target (tens of ms) in intensive interference environment functions to separate heterogeneous part in received signal that characterizes time of hitting window occupied by pulse burst being identified with main maximum of secondary radiation diagram of revolving components by adequate processing of pulse burst in frequency and time domains thereby enabling object identification. Device has analog-to-digital converter 1, digital computing units 2/1 - 2N, random-access memory 3, comparison unit 7, control unit 8, multiplexer 4, ranking unit 5, calculating unit 6, and inverter 9. Each digital computing unit has squarer 13, multiplier 10, adder 11, read-only memory 14, and shift register 12. Control unit has clock generator 15, pulse counters 16/1 - 16/3, and AND gate 17.

EFFECT: enhanced effectiveness of object identification.

1 cl, 4 dwg

FIELD: radio engineering, communication.

SUBSTANCE: method is carried out by replacing antennae of simulators and drives thereof with an antenna with a mobile phase centre, consisting of N radiators arranged linearly at an equal distance less than the wavelength in the propagation medium of the electromagnetic wave, from which m adjacent radiators at an appropriate moment in time are connected in-phase to a signal simulator through unmatched dividers and unmatched microwave switches, located in the branching feeder line from the divider to the radiator, as well as by introducing into the simulator circuit a register for rewriting the code of the position of the group of connected radiators under control of processor and providing change in the position of the phase centre of the virtual antenna. To simulate multiple targets, the radiation phase centre is moved into multiple positions while processing the signal at the station. The simulator comprises a digital delay line, parameters of which are switched synchronously with movement of the radiation phase centre.

EFFECT: simple device while improving reliability of simulation.

2 cl, 3 dwg

Adjustment shield // 2548690

FIELD: radio engineering, communication.

SUBSTANCE: adjustment shield simulates forward radio signals and radio signals specularly reflected from the earth, propagating from a missile and a target to a final homing area. The adjustment shield is located in the far zone of a radio direction-finding antenna and comprises laser and infrared emitters. To simulate signals from a missile transponder and signals reflected from a target, the shield is provided with a radio pulse generator with a frequency synthesiser.

EFFECT: high accuracy of adjustment.

3 dwg

FIELD: radio engineering, communication.

SUBSTANCE: apparatus for recognition of technical state of object comprises an antenna, a radar station, a filter channel unit, an autocorrelation function acquisition unit, a memory unit, a subtractor, a technical state evaluating device, a delay line, a multiplier, an analogue-to-digital converter, n switches and a "record" button. The listed components are connected to each other in a certain manner.

EFFECT: improved information value owing to recognition of the technical state of an object.

1 dwg

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to spacecraft on-board radar equipment designed for calibrating radar stations based on the radar cross-section. Spacecraft comprises a housing in the form of a rectangular prism (1) with a cross-section (2) in the form of a concave-convex polygon. Two faces (4, 5) of the prism of the same size with radio-reflecting surfaces face inside the housing of the spacecraft. The housing of the spacecraft is provided with two folding flat radio-reflecting plates (6, 7), which are pivotally connected to the faces (8, 9). The plates (6, 7) are provided with opening mechanisms and units for mounting to the prism (1) to form a dihedral comer reflector in the working position. The angle between the faces of the reflector is in the range of (90-Δ)° to (90+Δ)°, where Δ is defined by the condition: 0<Δ<18λ/a, where λ is the wavelength of the radar station being calibrated, a is the size of the face of the reflector. The spacecraft has on-board GLONASS and/or GPS consumer navigation equipment, a microprocessor, a microcontroller and a unit for interfacing the orientation and stabilisation system with the microcontroller.

EFFECT: broader functional capabilities of the spacecraft when calibrating radar stations operating on circularly polarised waves with concurrent reception of reflected signals, and during calibration based on the radar cross-section of high-potential radar stations in low radiation power operating mode.

9 cl, 10 dwg

FIELD: measurement equipment.

SUBSTANCE: invention relates to a system of simulation of electromagnetic environment. The system comprises a network (200) of emitting and/or receiving probes (Si) for testing of at least one antenna (300), channels (C) for connection of probes with a channel simulator (600), a block (400) of signal emission, a signal reception block (410), besides, one of blocks (400, 410) is connected to the simulator (600). According to the invention, a switching device (100) has the first measurement position, in which the device (100) connects the simulator (600) with at least one of probes via an appropriate channel (C) and connects the other block (410, 400) with the tested antenna (300), in the second position of calibration of channels (C) the switching device (100) connects the simulator (600) with the other block (410, 400) via the appropriate channel (C) without passage via the network (200) of probes (Si).

EFFECT: simplified and automated calibration for each channel, which does not depend on calibration of an actual network of probes.

13 cl, 8 dwg

FIELD: radio engineering, communication.

SUBSTANCE: method includes launching a reflector with a known radar cross-section to an artificial Earth satellite orbit, irradiating the reflector with radar signals, receiving and measuring the amplitude of the reflected signals. A minisatellite is carried to the artificial Earth satellite orbit as a radar cross-section reference, said minisatellite having a housing in the form of a rectangular prism and two flat radio-reflecting hinged faces, wherein the faces turn relative to each other to form a dihedral corner reflector, the edge of which is parallel to the lateral edge of the regular prism. The angle α between the faces of the corner reflector is given in a certain range in degrees. During flight, a radar station in the radio visibility zone of which the minisatellite is located is selected according to a given program by GLONASS and/or GPS navigation system receivers and an on-board computer. The method includes determining the position of the centre of mass of the minisatellite relative to the position of the selected radar station, as well as the orientation of axes associated with the coordinate system of the minisatellite relative to the line of vision of the radar station. Simultaneously, the on-board computer calculates and determines the spatial position of the bisector of the angle of the dihedral corner reflector relative to the line of vision of the calibrated radar station and the orientation system of the minisatellite then performs alignment thereof; further, the orientation system of the minisatellite maintains the alignment of the bisector of the angle of the dihedral corner reflector with the line of vision of the calibrated radar station until the end of the calibration session; as a result, the maximum of the main lobe of the scattering pattern of the corner reflector coincides with the line of vision of the calibrated radar station.

EFFECT: high accuracy of calibrating radar stations.

8 cl, 9 dwg

FIELD: physics, navigation.

SUBSTANCE: invention relates to radar and simulation-testing systems designed to evaluate properties of radar objects. The simulation-testing system for a radar station comprises a target for creating a full-scale environment in a field of view according to a given fly-by program. On-board the target there is a pilot-navigation system, connected to a satellite navigation system, and a measuring electronic device, both connected to a control station. The target is an unmanned aerial vehicle (UAV). The UAV comprises a wing, a tail unit, a fuselage, an engine and landing gear. The launch apparatus comprises a guide which is mounted with a pusher and a removable extensible stator on the side of the engine propeller. A support is mounted on the fuselage in its lower part on a longitudinal axis, said support being in contact with the end surface of the pusher at take-off. The landing gear of the UAV is installed in a compartment, on the wall of which an opening flap, which is connected to an automatic key, is mounted.

EFFECT: simple tests, improved operation and transportation conditions, enabling investigation of different types of radar stations at deployment sites without the necessary equipment.

6 cl, 5 dwg

FIELD: physics; control.

SUBSTANCE: invention can be used in automated air traffic control systems. The result is achieved due to that the disclosed method includes measuring coordinates of a reflecting object, followed by determining adjustment systematic errors; satellite navigators determining Cartesian coordinates of proper points of location of radar stations (Xn, Yn); the radar station to be adjusted measuring Cartesian coordinates of an aerial object (XOn, YOn); automatic control systems receiving, through an automatic dependent surveillance radio receiver, coordinates of the current location of the aerial object (XAZNn, YAZNn); interpolating all received Cartesian coordinates to a single moment in time; mathematically averaging the obtained Cartesian coordinates of the aerial object interpolated to a single moment in time Xmc=XO1+XO2++XON+XAZNn+1;Ymc=YO1+YO2++YON+YAZNn+1 calculating the adjustment for each of the radar stations to be adjusted Δβn=arctg(YonYnXonXn)arctg(YmcYnXmcXn)=arctg(YonYnXonXnYmcYnXmcYn1+YonYnXonXnYmcYnXmcXn)Dn=(XmcXn)2+(YmcYn)2(XonXn)2+(YonYn)2; comparing the calculated adjustments Δβn, ΔDn with the resolution of each of the radar stations to be adjusted and, if the adjustment is greater than the resolution of one of the radar stations to be adjusted, said radar station is re-tuned, and measurements and calculations are repeated until the adjustment value is less than the resolution of all radar stations to be adjusted.

EFFECT: high accuracy of adjustment.

1 dwg

FIELD: physics, navigation.

SUBSTANCE: invention relates to radar. The method includes measuring coordinates of a reflecting object followed by determination of systematic adjustment errors; using a satellite navigator to determine Cartesian coordinates of the natural position of the radar station (x1, y1); using the radar station to be adjusted to measure Cartesian coordinates of an aerial object located in the coverage area of the radar station (x2, y2); the radar station receiving, using an automatic dependent surveillance radio receiver, coordinates of the current location of the aerial object (x3, y3) and determining the value of the azimuth and range adjustment for the radar station to be adjusted using corresponding formulae.

EFFECT: high accuracy of adjusting radar stations.

1 dwg

FIELD: physics, navigation.

SUBSTANCE: invention relates to means for metrological support of receiver-indicators of GLONASS space navigation systems. The reference work station for precision calibration of delay of lettered frequency envelopes of GLONASS signal receivers consists of a test signal source, the calibrated receiver and a personal computer for processing calibration results. The test signal source used is synthesiser of an array of test frequencies that are phase-modulated by ±90° using range-finding code of a GLONASS pseudorandom sequence. Phase incursions are input into the personal computer, said phase incursions being successively measured by the carrier monitoring system of the calibrated receiver over an interval Δt. Phase incursions measured at the same intervals Δt of the hardware copy of the carrier monitoring system of the calibrated receiver are subtracted therefrom and said differences are divided by Δt to obtain phase response readings for frequencies. Delays directly caused by nonlinearity of the frequency response are calculated; group delay is measured; said delays are summed to obtain spectral density of the delays, or partial delays, which are averaged with the spectrum of the pseudorandom sequence of the range-finding code, successively shifting the centre frequency of the spectrum to the closest lettered frequency.

EFFECT: high accuracy of calibrating the delay of a lettered frequency envelope.

5 dwg

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to radar, radio communication, radio navigation and radio control and can be used in radio electronic systems for detecting signals. The integrated device is a multichannel device and has, in each channel, a matched filter, two function generators, made in a certain manner, and a data transmission line, as well as an adder and a threshold device. The listed components are connected to each other in a certain manner.

EFFECT: smaller volume of transmitted information and high signal-to-noise ratio at the output of the device.

2 dwg

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