RU2012101358A - METHOD FOR MEASURING AN EFFECTIVE AREA OF SCATTERING OF OBJECTS AND A MULTI-POSITION RADAR-RADAR MEASURING COMPLEX FOR ITS IMPLEMENTATION - Google Patents

Abstract

1. A method of measuring the effective scattering area (EPR) of objects, which consists in irradiating the test object with a pulse signal of a fixed wavelength, fixed power and fixed polarization of the linear basis emitted by the measuring radar antenna in the direction of the test object, re-emitting the signal scattered by the test object from the direction corresponding to the given the angle of the separation of the RIC in the horizontal plane using a system of M passive repeaters in the direction of the receiving antenna diversity about the receiving device, receiving this signal separately from each passive repeater, recording and then comparing the powers of the signals scattered by the test object and the calibration reflector with a known bistatic EPR located at the location of the test object, instead of it, characterized in that the studied object is additionally irradiated with N -1 pulsed signals of fixed power and fixed polarization N-1 measuring radars of a fixed wavelength, the signal scattered by the object under study For the appropriate separation angles, they are reflected using a system of passive repeaters with a low (less than - 30 dB) level of the side lobes of the bistatic scattering indicatrix installed on a special measuring path providing a quasi-plane distribution of the electromagnetic field on one line coinciding with the fixed direction of the optical axes of the receiving antenna system spaced receiving devices spanning the wavelength range λ, and from the corresponding installation location of each passive repeater at

Claims (2)

1. A method of measuring the effective scattering area (EPR) of objects, which consists in irradiating the test object with a pulse signal of a fixed wavelength, fixed power and fixed polarization of the linear basis emitted by the measuring radar antenna in the direction of the test object, re-emitting the signal scattered by the test object from the direction corresponding to the given the angle of the separation of the RIC in the horizontal plane using a system of M passive repeaters in the direction of the receiving antenna diversity about the receiving device, receiving this signal separately from each passive repeater, recording and then comparing the powers of the signals scattered by the test object and the calibration reflector with a known bistatic EPR located at the location of the test object, instead of it, characterized in that the studied object is additionally irradiated with N -1 pulsed signals of fixed power and fixed polarization N-1 measuring radars of a fixed wavelength, the signal scattered by the object under study For the appropriate separation angles, they are reflected using a system of passive repeaters with a low (less than - 30 dB) level of the side lobes of the bistatic scattering indicatrix installed on a special measuring path providing a quasi-plane distribution of the electromagnetic field on one line coinciding with the fixed direction of the optical axes of the receiving antenna system spaced receiving devices spanning the wavelength range λ _N , and from the respective installation site of each passive repeater separation angle γ _m temporary selection of signals from each passive repeater on spaced receiving devices is carried out due to the difference in the path of rays on the paths R _2m and R _3m , receive, measure the power of each coincident and orthogonally polarized component, compare it with the power of the signals of the corresponding polarization, reflected from the calibration reflector with a known bistatic EPR at the corresponding polarization, and record the powers of the coincident and orthogonally polarized components of the scattered m object and a calibration reflector of signals, and the studied object or calibration reflector is rotated alternately in the horizontal plane at fixed values of the orientation angle in the vertical plane and, when processing the measurement results, take into account the current orientation of the studied object or calibration reflector for all the studied values of the separation angles and wavelengths, and also the relative position of each measuring radar of a fixed wavelength relative to the investigated object and each passive retran slator. 2. A multi-position radar measuring complex for measuring the EPR of the studied objects, containing a clock generator with a fixed-wavelength radar, consisting of a fixed-wave pulse transmitter and a transceiver antenna, an object under study, a calibration reflector, a rotary platform with a sensor for the current angular position of the object under study or calibration reflector, M passive repeaters in the form of flat plates mounted on the surface of the earth, spaced receiving device with a receiving antenna and a recording device, while one output of the clock generator is connected to a pulse transmitter of a fixed wavelength, the output of which is connected to a transmit-receive antenna connected via a radar channel "transmit-receive antenna - object under study or calibration reflector - passive repeater" with the object under study or a calibration reflector and a passive repeater, which is connected via the radio channel "transceiver antenna - signal scattered by the object l - passive repeater - receiving antenna ”with a transceiver antenna, an object under study or a calibration reflector and a spaced receiving device, the output of which is connected to a recording device, while the second output of the clock generator is connected to a spaced receiving device to provide the gating of a useful diffused scattered passive repeater under study object or calibration reflector of the signal, in range, and the output of the sensor of the angular position of the investigated object or a calibration reflector mounted on a rotary platform, connected to the input of the same recording device, characterized in that it additionally includes N-1 measuring radars of a fixed wavelength, each of which has a waveguide switch, two antenna switches and a transceiver polarizing splitter, through which the transceiver antenna is connected to the corresponding antenna switch, the second outputs of which are connected to the corresponding inputs of the two-channel receiver The properties of the matching and orthogonal polarization of the measuring radar, the two outputs of which are connected to the corresponding inputs of the recording device, and each diversity receiving device consists of a two-channel receiving device of the matching and orthogonal polarization of the diversity receiving device, two antenna switches and a receiving polarizing splitter, and the receiving antenna through the receiving polarizing the splitter and the corresponding antenna switch is connected to the corresponding input for vuhkanalnogo receiving device matching and orthogonal polarization of a spaced receiving device, the outputs of which are outputs of a spaced receiving device, and each passive repeater consists of a low-reflective mast, on which is mounted a flat rhombic plate with the possibility of pointing it in angular coordinates and moving in the vertical plane, and passive repeaters are installed on one line coinciding with the optical axis of a fixed direction of the receiving antennas spaced apart receiver devices, and the second output of the clock generator is connected to the third input of the two-channel receiving device of the matching and orthogonal polarization of the diversity receiving device to provide the gating of a useful signal scattered by the object or calibration reflector at the corresponding separation angle, in range, each measuring radar of a fixed wavelength set at a distance from the investigated object $$R_{\mathrm{one}}=\frac{{\left(l_{\mathrm{BUT}PR\partial }+l_{\mathrm{about}b.\max }\right)}^2}{{\lambda }_N}$$

where l _{Aprd (prm)} is the aperture size of the transceiver antenna; l _rev.max - maximum linear size of the investigated object; λ _N is the working wavelength of the radar detector of a fixed wavelength and RIC clock pulses synchronized from a single generator, and passive repeaters due to the use of a flat rhombic plate have a low level of side lobes of the bistatic scattering indicatrix and the dimensions of which provide the required amplitude-phase distribution of the electromagnetic field at the object under study and on the paths R ₂ "the object under study is a passive repeater" and R ₃ "passive relay is a receiving antenna of a diversity receiving receiver trinity "in accordance with the requirement of the far zone $$R_2=\frac{{\left(l_{\mathrm{about}b.\max }+a_p\right)}^2}{{\lambda }_N}$$

$$R_3=\frac{{\left(a_p+l_{\mathrm{BUT}PRm}\right)}^2}{{\lambda }_N}$$

where l _rev.max is the maximum linear size of the investigated object; a _p is the maximum linear size of the plate of a flat passive repeater; l _Aprm is the size of the aperture of the receiving antenna of the diversity receiving device at a wavelength of λ _N , moreover, the angle of orientation of the axis of the line of passive repeaters θ _p is determined by the minimum distance R _{2 min} , which is selected from the condition of the "far zone" θ _p = arcsin (R _{2 min} / R ₁ ), the angle of orientation of the passive repeater relative to the axis of the line of their construction α _Pm provides a mirror multipath scattered by the studied object or the calibration signal reflector in the direction of the receiving antenna diversity reception apparatus α _Pm = (γ _m + θ _r) / 2, the minimum separation angle RIC determined from the distance zone to ensure the system "adoptive Antenna diversity receiving apparatus - the first passive repeater "line $$R_{31}>>{\gamma }_{\min }={\gamma }_{\mathrm{one}}=arctg\frac{R_{31}\sin {\theta }_p}{R_2-R_{31}\cos {\theta }_p}$$

where R ₃₁ is the distance between the receiving antenna of the diversity receiver and the first passive repeater of the line, provided R ₃₁ ≥ (a _Pm + l _max ) ² / λ, and the distance between adjacent passive repeaters of the line ΔR ₃ = R _3m -R _{3 (m -1)} should be not less than the worst resolution in range of a multi-position RIC $$\Delta {\text{R}}_{\text{max}}\ge \text{c}{\tau }_{\text{u}\text{max}}\text{/ 2}$$

, the passive repeaters in the line are offset one from another by the projection of the previous passive repeater onto a plane orthogonal to the line axis ΔC _m = a _Pm sin [(γ _m + θ _P ) / 2], and the total shift of the passive repeaters in the line does not exceed the width radiation patterns of a system of receiving antennas of diversity receiving devices with the highest resolution δΘ prm _0.5 at half power level $$C^{{\displaystyle \sum }}m={\displaystyle \sum _{m=\mathrm{one}}^M\Delta C_m}\le R_{\mathrm{one}m}tg\delta g_{PRm0.5}.$$