Apparatus for measuring scattering cross-section of large-size objects |
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IPC classes for russian patent Apparatus for measuring scattering cross-section of large-size objects (RU 2483317):
   
 Method of calibrating radar station operating on circularly polarised waves with parallel reception of reflected signals based on value of effective radar cross-section during dynamic measurement of effective radar cross-section of ballistic and space objects / 2477496
Invention can be used when calibrating radar stations from the effective radar cross-section (ERC) value. The disclosed method involves launching a booster rocket (BR) with a reference reflector (RR), irradiating the reflector with radar signals, receiving and measuring the amplitude of the reflected signals. As an ERC reference, an angle reflector (AR) is transported to an altitude higher than 100 km, said AR consisting of two flat radar-reflecting half-discs turned at an angle ranging from (90-Δ)° to (90+Δ)°, where Δ is determined from the ratio 0<Δ<18λ/a, λ being the wavelength of the calibrated radar station. Before launching, the AR is put into a guiding container, while aligning the longitudinal axis of the container with the bisector of the angle between faces of the AR. Before separating the AR from the BR, the last stage of the BR with the container is positioned by the BR control system such that the longitudinal axis of the container is directed along the line of sight of the radar station. The AR is separated from the BR on the line of sight of the radar station such that the main lobe of the scattering indicatrix of the AR is directed towards the radar station, and its maximum coincides with the line of sight of the radar station. The AR is also spun around an axis which coincides with the bisector of the angle between its faces.
 Method of calibrating radar station from effective radar cross-section value during dynamic measurement of effective radar cross-section of analysed objects / 2477495
Invention can be used when calibrating radar stations from the effective radar cross-section (ERC) value. The disclosed method involves launching a reflector with a known ERC value to an orbit around the Earth, irradiating the reflector with radar signals, receiving and measuring the amplitude of the reflected signals. As an ERC reference, an angle reflector (AR) is transported to a satellite orbit, said AR consisting of two flat radar-reflecting half-discs turned at an angle ranging from (90-Δ)° to (90+Δ)°. Before launching, the AR is put into a guiding container, while aligning the longitudinal axis of the container with the bisector of the angle between faces of the AR. The container is mounted on-board the spacecraft. The spacecraft is positioned such that the longitudinal axis of the container is directed along the line of sight of the radar station. The AR is separated from the spacecraft on the line of sight of the radar station such that the main lobe of the scattering indicatrix of the AR is directed towards the radar station, and its maximum coincides with the line of sight of the radar station. The AR is also spun around an axis which coincides with the bisector of the angle between its faces.
 Radar high-frequency frequency-modulated doppler signal simulator / 2469348
Radar high-frequency frequency-modulated Doppler signal simulator is meant for use in complex signal generators, as well as in modulating systems for testing and investigating radio engineering systems. The system includes two phase modulators, a balanced modulator, a phase detector, a controlled high-frequency signal generator, a directional coupler, a controlled attenuator, connected to each other in a certain manner.
 Method of calibrating active phased antenna array / 2467346
Invention relates to antenna equipment and is meant for calibrating active phased antenna arrays. The method of calibrating an active phased antenna array, in which in order to calibrate the receiving part of the transmit-receive channel, a control signal is transmitted to the input of the receiving part of each channel; parameters of the received signal are measured; adjusting coefficients which are used to adjust parameters of the receiving part of the channel are formed based on the measurements; to calibrate the transmitting part of the transmit-receive channel, a control signal is transmitted to the input of the transmitting part of each channel; parameters of the transmitted signal are measured; adjusting coefficients which are then used to adjust parameters of the transmitting channel are formed based on the measurements; calibration of the receiving part of the transmit-receive channels is carried out in pairs in receive mode, wherein the control signal is picked up from the output of the receiving part of the transmit-receive channels; calibration of the transmitting part of the transmit-receive channels is carried out in pairs in transmit mode, wherein part of the signal power tapped from the output of the corresponding transmit-receive channel and passing through the receiving part of that channel is used for calibration; during calibration, phase shift and amplitude difference of the signal from the output of the calibrated channel relative the reference channel are determined; the same reference channel is used for calibrating all channels.
 System for built-in control and calibration of monopulse radar station / 2459219
During control, a portion of probing signal power, which is fed to a circuit signal simulator and through a circulator to an adder with a heterodyne simulator signal, is output from a monopulse radar station; the resultant signal is fed to a mixer, conveyed at an intermediate frequency and is fed to a recirculation circuit, which is built on series-connected second adder and delay line, where the damped batch of delayed pulses returns to the mixer, where it is conveyed at carrier frequency using the heterodyne signal, passes through the circulator to series-connected valve, test antenna and radio communication channel to the antenna of the monopulse radar station. The processor of the monopulse radar station controls the process of built-in control in signal search, capture and tracking modes; measurement of bearing characteristics takes place based on target search results with scanning of the antenna system; capturing and tracking results are used to determine coordinates of the simulated target, controlled parameters of the transmitter, the receiver and signal of the detector; by comparing the controlled parameters with rated values, the processor determines accuracy of the monopulse radar station and deviation of calibration, which it then stores and takes into account when measuring coordinates of targets during combat.
 Method of calibrating mobile shortwave direction finder with multielement antenna array / 2451948
Invention can be used to calibrate radio signal source direction finders, particularly mobile shortwave (SW) direction finders with a multielement antenna array (AA). The method involves measuring the required number of positions of the radiator for control measurements, the distance between the position of the control radiator (CR) and the closest antenna component (AC) and the coordinate of the positions for installing the CR; receiving a control signal for an N-element distributed AA; frequency selection and measurement of the phase of the received signal pulses; selection of a reference AC, after which CR are successively installed at each given position; determining the initial disparity of measurements of phase difference between each (N-1)-th and the reference AC; and the mean-square deviation (MSD) of the measurement results is calculated; through successive iterations, adjustments are made to the estimate of true coordinates of the AC and the estimated phase defects of feeders and the disparity of phase difference between each (N-1)-th and the reference AC for each position of the CR is re-determined, thereby achieving the minimum attainable MSD of measurement results; and the coordinate values of phase centres of the AC and allowable values of phase offset of the AA feeders, needed for measuring bearings, with minimum error, to signal sources monitored by the mobile direction finder, are determined.
 Radar systems power supply control device / 2449343
Device to control power supply to radar systems comprises the following: a clock pulse oscillator; a reprogrammable logic circuit (PLIC); comprising a logical device; four tumblers; three power supply sources; three relays; three generators of bit commands; three light diode indicators; and eight noise eliminators included into the PLIC, each including two pulse counters, an inverter, a trigger; and links between them.
 Imitator of moving objects / 2449308
Imitator of moving objects comprises a synchroniser, a unit of signal imitation control, three frequency modulators, a pseudorandom signal generator, a low pass filter, two generators of movable strobes, two strobing units, six controlled attenuators, a controlled noise generator, a controlled delay element, a summator, two phase commutators and three amplifiers of intermediate frequency that are connected to each other in a certain manner.
 Calibration method of decametric radio direction-distance finder / 2422846
On the basis of additional information obtained as a result of identification and extraction of signals of beams of common and non-common polarisation, increase in content of calibration information to two segments of calibration data, which differ by polarisation, and use of formation technology of base of calibration data of ionospheric waves on the basis of combination of measurements made on actual direction finder and its dummy corrected as to actual ionospheric signals.
 Radar target simulator / 2412449
Before combat mission, simulator is calibrated. Signal received from scanning radar is attenuated by first attenuator before conversion into intermediate frequency and delay thereon, by appropriate magnitude that sets maximum signal at digital delay circuit input. Before inverse conversion of delayed signal into carrier frequency, it is attenuated by second attenuator by magnitude equal to difference between signal attenuation in radio line radar - target and the sum of signal attenuation in first attenuator and constant losses in simulator. To set attenuation of first attenuator in calibration, first attenuator output signal is detected, and digitised. Mismatching of digitised signal maximum is determined in each scanning cycle relative to tolerable level used by computer to adjust signal attenuation for mismatch decrease till it becomes lower than tolerance.
 Method of adjustment of optical axis of viewfinder and electrical axis of aerial / 2252427
Viewfinder is disposed at specific distance from mechanical axis of aerial. Viewfinder is tightly connected with antenna aperture plane. Optical axis of viewfinder is directed in parallel to mechanical axis of aerial. Then electrical axis of aerial is guided to phase center of ancillary aerial which is disposed together with geodetic mark onto post. Optical axis of viewfinder is guided onto geodetic mark. Geodetic mark is tied to angular position detectors and stays apart from phase center of ancillary aerial for distance being equal to shift of viewfinder from mechanical axis of aerial to the plane of normal optical axis of viewfinder. Optical axis of viewfinder is guided onto center of aperture of ancillary aerial. Difference in coordinates is determined by angle of location of initial and final position of viewfinder optical axis. Sword is turned around axis being perpendicular to plane of sword and crossing center of ancillary aerial aperture by angle determined by the relation given in the description of the invention. Electrical axis of aerial is guided onto phase center of ancillary aerial and optical axis of viewfinder is guided onto geodetic mark.
 Target fluctuating signal generator / 2253129
The device having a control panel, storage unit, synchrosignal generator, first, second and third on-line memories, unit for formation of target relative coordinates, unit for formation of the maximum target signal intensity, first, second, third and fourth synchronizers, unit for formation of the current intensity of the target signal, digital-to-analog converter, noise generator, adder uses also a correlator, first and second detectors, first and second multiplier units, first and second random number generators, which provides for formation of amicably fluctuating and quickly fluctuating bursts of pulses reflected from the radar targets, internal noise of the receiver and synchronizing signals at the output of the radar receiver in the rate of radar functioning and with due account made for motion of the ship-carrier.
 Generator of reflected radar signals from disturbed sea surface / 2253130
The device has a control panel, memory unit, preliminary recording control unit, unit for formation of carrier relative coordinates, readout and synchronizing unit, on-line memory unit, unit for formation of video signal, unit for formation of carrier polar coordinates, noise formation unit.
 Mode of controlling working capacity of airborne receiver indicator of satellite radio navigational system / 2254591
The mode is that the altitude HRA of the flight of a flying vehicle is measured with the help of installed on it a radio altimeter (RA), the altitude hr of an area above which a flying vehicle flies at the moment of the altitude measuring using for this purpose data about planned coordinates from the output of the receiver indicator of the satellite radio navigational system and digital map of an area, an absolute altitude Ha= HRA +hr, is calculated and compared with the altitude HRI, taking from the output of the receiver indicator and a signal of its working capacity is formed if |Ha- HRI| is smaller than the installed threshold Th.
 Radio-signal dynamic memory device having series binary fiber- optic system / 2255426
In order to enhance identity of copy generation while retaining ability of controlling input radio signal replication process, proposed device is provided with newly introduced (N -1) fiber-optic four-terminal networks, each of them incorporating Y-type internal adding and separating fiber-optic directional couplers.
 Radio engineering training device / 2260193
Device has radio-location station, first high-frequency generator, modulator, first counter, scanning generator, second counter, heterodyne, first mixer, first intermediate frequency amplifier, first amplitude detector, video-amplifier, third counter, cathode-ray tube, second, third and fourth high-frequency generators, first and second adders, switches, phase-rotators and on 90°, second mixer, second intermediate frequency amplifier, multiplier, narrow-band filter, second amplitude detector, key and frequency converter.
 Method for adjustment of radiolocation station antenna / 2262117
Method includes using auxiliary antenna and geodesic mark, linked with indicators of angular position of target antenna, viewfinder is positioned near opening of subject antenna, rigidly linked to opening plane of subject antenna. Flat metallic screen is inserted, to which emission from auxiliary antenna is directed, auxiliary antenna and geodesic mark as light source are positioned behind subject antenna at remote zone distance. Electric axis of subject antenna is directed using its rotation gear according to one of minimum methods to phase center of auxiliary antenna, screen is mounted so, that beams, falling o it from auxiliary antenna and geodesic mark, were reflected respectively to whole plane of opening of target antenna and inlet eye of viewfinder. Angular deflection of optical axis of viewfinder from direction to center of image of geodesic mark on screen determines adjustment of target antenna.
 Radar target simulator / 2267798
The radar target simulator has a super high frequency module consisting of successively connected arrangements: an automatic regulator of power, an impulse modulator, an amplitude modulator, a switch of the power level and a digital attenuator, a communication line, a horn antenna, a group of keys, the first semiconductor storage, an interface of a multiplex bus, a synthesizer of Doppler frequencies, a second semiconductor storage and a multiplying digital-analogue converter. The increasing of the accuracy of the installation of the output power is provided due to possibility of its correction by way of changing the intensity of the amplitude modulation of the super high signal for each meaning of the value of fading.
 Emulation device of an active response radar connected with a surveillance radar / 2268477
It is also used for instruction and training of the operators of the surveillance facilities connected with an active response radars in the conditions of the presence of a great number of targets moving on complex trajectories. The essence of the invention is in that the arrangement holds an oscillator of the signals of the targets including the targets carrying responders. In it there is a control panel of the active response radar, a selector of characteristics of response signals, a synchronizer of response signals, an operating response signals storage device, a decoder of the characteristics of response signals, a counter of tact impulses, a former of identification markers and an adder unit with their connections that provides emulation of the operation of the active response radar connected with the surveillance radar at changing their modes of operations in the process of obtaining radar information about common and individual characteristics of the target carrying a responder in the zone of operations of the mentioned radar facilities with the purpose of verification of their terminal facilities of the secondary processing of radar information, instruction and training of the operators of the surveillance radar.
 Method of controlling of an airborne mono impulse radar station with a built-in unit and an arrangement for its realization / 2268478
The essence is in that in the reference point of the bearer of the rocket or of the streamlined antenna cover a sound is installed. It is made in the shape of a half-wave antenna whose arms are linked up to a nonlinear element. At receiving the order «Control» the transmitter of the airborne mono pulse radar station forming super high frequency vibrations on the carrier frequency fc is connected with the power detector and its power is evaluated, vibrations on the super high frequency fo which is in n times less than the frequency fc are created and delayed in time relatively to the super high signals of the transmitter of the frequency fc and the sound reradiating the signal on the frequency fc is exposed to them. These signals are received and processed with standard facilities of the airborne mono impulse radar station, the imitated distance, the angle α of the azimuth and the place β are measured and compared with the specified parameters and decision about the efficiency of the airborne mono impulse radar station is accepted if the power of the transmitter is no less than admissible and the differences of the specified and the measured angles α and β do not exceed the admissible meanings.
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FIELD: physics. SUBSTANCE: apparatus for measuring scattering cross-section (SCS) of large-size objects, having series-connected pulsed transmitter, antenna switch, antenna, receiver and computer, the second input of which is connected to a control panel, the second input/output of which is connected to the main rotary support on which the measured object is placed, the third input/output of the control panel is connected to an additional rotary support at whose centre there is a SCS metre, which is in form of a triangular angle reflector, wherein the additional rotary support is mounted on a linear displacement device which is connected to the fourth input/output of the control panel, wherein the additional rotary support is placed between the main rotary support and the transmitter in the same pulsed volume with the measured object. EFFECT: high accuracy of measuring SCS of large-size objects in the decimetre and metre wavelength range. 1 dwg
The invention relates to radar systems, in particular to radar measurements, and can be used on open radio ranges. Measurement of the effective area of the radar cross section (RCS) on the open measuring ranges are characterized by a large amount of preparatory work, one of which is to set the object on a rotation device, which is located in the measuring volume. During measurements, you must delete the object to be measured from the measuring volume and replace it with a reference reflector (measure EPR) for calibration. The frequency of calibration due to the metrological characteristics of the measuring system and to achieve the required accuracy of the measurement results must be no more than the interval of the long-term instability of the parameters of the measuring equipment of the complex. However, for some types of full-scale large objects that do not have the possibility of Autonomous maneuvering (hereinafter called large objects), the time of replacement of the reference reflector and the subsequent re-installation of the object on the turntable substantially exceeds the interval long-term instability of the main metrological characteristics of measuring equipment complex is, that leads to increased measurement errors. Famous complex of RAT SCAT for measuring radar cross-section targets [Marlow Watson and van ascent of Keter. The complex of RAT SCAT for measuring radar cross-section targets. TIER, 1965, t, No. 8, str]. The complex of RAT SCAT contains a pulse transmitter, antenna switch, antenna rotation device, the object of measurement, the reference reflector, receiver, transmitter, remote control, the pulse transmitter connected to the input of the antenna switch, the output of which is connected to the antenna input, the second output of the antenna switch is connected to the receiver, the output of which is connected to the input of the transmitter, the second input of the transmitter is connected to the rotary support. The EPR measurements using complex RAT SCAT manufactured as follows. Initially calibrates equipment. The calibration procedure is as follows: measured EPR retractable reference reflector relative to the sphere; to maintain calibration in the measurement process, this reflector is installed in the cell resolution in range different from that which is subject to measurement object. Setting the reference reflector in another cell resolution in distance leads to errors of measurement due to different ur the init background in place of the object and the reference reflector. The closest in technical essence is a Device for measuring the effective area of the large scattering objects [Russia, Patent 2308043, G01S 13/00, 2007], which contains serially connected pulse transmitter, antenna switch, antenna, receiver and transmitter to the second input of which is connected to the control unit, the second input-output of which is connected to the main the rotary support on which is placed the object to be measured, and the third input-output control unit connected to additional support and turning the device on which the eccentric is installed measure of the effective area of dispersion, and the additional rotation device placed between the main support and turning device and transmitter in one pulse volume with the measured object. The value of the distance R, which may be made the measure of the EPR from the center of a turntable, is determined by the condition: R≥λ/Δφ, where λ is the wavelength, Δφ - sector analysis. This condition is defined as a philosophy that within sector analysis Δφ must meet at least two periods of oscillation of the electromagnetic wave. Only in this case, the measurement error does not exceed 0.5 dB. For example, when λ=3 cm and Δφ=0,1 glad distance endurance the sa measures EPR from the center of a turntable are R=30 cm, what is acceptable for conducted measurements. When λ=30 cm and Δφ=0,1 pleased the value of the distance of removal measures EPR from the center of a turntable are R=3 m When λ=3 m and Δφ=0,1 pleased the value of the distance of removal measures EPR from the center of a turntable are R=30 m The above example clearly illustrates the impossibility of using this device for decimeter and meter wavelengths. With increasing wavelength, if not to increase the distance of removal measures EPR from the center of a turntable, will increase the measurement error. And if you increase the distance of removal measures EPR from the center of a turntable of tens of meters, it will be impossible to sell such a device. A disadvantage of this device is that its use in UHF will lead to large measurement errors EPR objects, and in the meter wavelength range of such a device is generally not implemented. Thus, the technical challenge is to improve the accuracy of measurement of EPR large objects in the decimeter and meter wavelengths. A new technical result is achieved due to the fact that in the known device for measuring the RCS of large objects, with the holding serially connected pulse transmitter, the antenna switch, antenna, receiver and transmitter to the second input of which is connected to the control unit, the second input-output of which is connected to the main the rotary support on which is placed the object to be measured, and the third input-output control unit connected to additional support and turning the device on which you installed the measure of the effective area of dispersion, and the additional rotation device disposed between the main support and turning device and transmitter in one pulse volume with the measured object, introduced a linear device, which is installed an additional rotation device in the center of which is placed a measure of the effective area of dispersion, made in the form of a trihedral corner reflector, in addition, the linear device connected to the fourth input-output control. Explain the essence of the proposed technical solutions. The claimed technical solution for calibration use a linear device, which is installed an additional rotation device. Thus a measure of the effective area of dispersion is made in the form of a trihedral corner reflector, which is placed in the center for additional support and turning the mouth of the STS. As measures of EPR for the long-wavelength part of the range, it is preferable to use a trihedral corner reflectors, featuring a wide chart backscatter and high ESR. For the implementation of linear additional turntable along the lines of "antenna - main bearing slewing device it is placed on a linear device, which is connected to the fourth input-output control. The analysis of the prior art reveals that the inventive device is characterized by a set of characteristics is identical for all signs contained in proposed by the applicant claims, absent, which indicates compliance of the claimed invention, the criterion of "novelty". Search results known solutions in this and related areas of technology in order to identify characteristics that match with the excellent features of the proposed device, showed that public sources are not identified solutions that have the signs consistent with its distinguishing characteristics, namely the introduction of more devices linear movement, on which is installed an additional rotation device, in the center of which there is a measure of the effective area of dispersion, made in the form trigger the frame corner reflectors, in addition, the linear device connected to the fourth input-output control. The prior art also has not been confirmed by the known influence of the distinctive features of the claimed device on the technical task of improving the accuracy of measuring large objects in the decimeter and meter wavelengths, therefore, the claimed invention meets the condition of "inventive step". The invention of the Device for measuring the RCS of large objects" industrially applicable, as set describing its features, provides the possibility of its implementation, performance and reproducibility for measuring EPR large objects in the decimeter and meter wavelengths, so as to implement the claimed device can be used known materials and equipment. The figure shows the device for measuring the effective surface area of the scattering of large objects. Device for measuring the RCS of large objects consists of a pulse transmitter 1, the antenna switch - 2, antenna 3, the main turntable - 4, the measured object 5, additional turntable - 6, the effective area of dispersion - 7, the device lineing the move - 8, the control panel 9, the computer 10, a receiver 11. Pulse transmitter 1, the antenna switch - 2, antenna 3 - receiver 11, the computer 10 are connected in series. The measured object 5 is installed on the main bearing slewing device 4, a measure of the effective area of dispersion is made in the form of a trihedral corner reflector 7 and is installed in the center of a turntable - 6, which is placed on the linear device - 8. Remote control - 9, the first output is connected to the computer 10, the second input-output is connected with the main supporting-rotator - 4, the third input-output remote control 9 is connected with additional support and turning device 6, the fourth input-output remote control 9 is connected with a linear device. Device for measuring the RCS of large objects is as follows. Main bearing slewing device with 4 sets of measured object 5. With remote control - 9 and simultaneously the pulse transmitter 1 and the main rotation device - 4. Pulse transmitter 1 through the antenna switch 2 and the antenna -3 radiates the signal in the direction of the measured object 5. The measured object 5 is rotated on the platform of the main turntable - 4. the use of receiver - 11 accepted the reflected signals from the object of measurement - 5 (Pnin the process of total turnover turntable 360 degrees and are fed to the computer 10. Simultaneously, the computer 10 from the main turntable - 4 information on the angle φ measured object 5, and the result is a pie chart EPR object of power. Then continue to rotate the object to be measured is 5 up until the power level of the signal reflected from it will not be approximately equal to the power level of the signal from measures EPR PFLand this value is known and is obtained by calculation. Then additional rotation device 10 is placed on the linear device 8, and the center of a turntable - 6 set the measure EPR, made in the form of a trihedral corner reflector - 7 with the famous EPR σFL. With remote control - 9 and simultaneously the additional rotation of a turntable 6 and the linear device - 8. Then, using receiver - 11 accepted the return signal is fed to the computer 10, which is determined by the maximum signal Pmaxreflected from measures EPR - 7. Using receiver - 11 registers the power level of the vector sum of the signals reflected from measured about the project - 5 and rotating action EPR 7, and is fed to the computer 10, where the selected maximum Pmaxand minimum Pminthe values of the power levels of the reflected signals to determine the EPR in the interaction point of the measured object 5 to measure the EPR - 7 by the formula
This formula is obtained by solving the system of equations (2) and (3) for the interaction between the two reflectors
Then with the remote control - 9 are disconnected simultaneously, the additional rotation of a turntable 6 and the linear device - 8. Additional turntable - 6 measure EPR - 7 and the linear device - 8 derived from the irradiation zone (working volume). The point on the object with the EPR σEOIuse as a reference. And then the computer 10 calculates the EPR of the measured object 5 for any angle φ using the EPR at the point of interaction σEOIand the power of interaction PEOIaccording to the formula The use of the inventive device allows to increase the accuracy of the RCS of large objects in the decimeter and meter wavelengths. Device for measuring the effective area of the large scattering objects containing serially connected pulse transmitter, the antenna switch, antenna, receiver and transmitter to the second input of which is connected to the control unit, the second input-output of which is connected to the main the rotary support on which is placed the object to be measured, and the third input-output control unit connected to additional support and turning the device on which you installed the measure of the effective area of dispersion, and the additional rotation device disposed between the main support and turning device and transmitter in one pulse volume with the measured object, characterized in that it introduced the linear device along the line "antenna - main support-turning the device on which you installed additional rotation device, in the center of which there is a measure of the effective area of dispersion, made in the form of a trihedral corner reflector, in addition, the linear device connected to the fourth input-output control.
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