RU2595775C1 - Method and device for remote detection and recognition of objects with nonlinear markers - Google Patents

Abstract

FIELD: radars.

SUBSTANCE: invention relates to non-linear radar and can be used for remote detection and recognition of objects located outside zone of visual surveillance. Method consists in that search engine irradiates a search object with a nonlinear marker probing signal at frequency f₀ and receives response at frequency f₀+Δf, where Δf << (f)₀. Probing signal and response signal are encoded and decoded, and nonlinear scatterer included in non-linear marker converts high-frequency energy of received probing signal into DC voltage energy to include active response signal at frequency f₀+Δf. Device implementing said method consists of a search system comprising a transmitting device, band-pass filter, receiver, indicator and an antenna with corresponding links, and nonlinear marker comprising an antenna, band-pass filter, transmitting device, indicator, nonlinear scatterer, decoder of code packages, key and accumulator with respective connections. Transmitting device of search system and band-pass filter of nonlinear marker are tuned to frequency f₀, transmitting device of nonlinear marker, band-pass filter of search system and receiver are tuned to frequency f₀+Δf, both transmitting devices comprise generators of code packages, receiver comprises a decoder of code packages, and both antennae are receiving-transmitting with bandwidth from f₀ to f₀+Δf and are interconnected via radio channel.

EFFECT: technical result is longer detection range of search objects with nonlinear markers with high noise immunity and possibility of recognising search objects.

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Description

The invention relates to non-linear radar and can be used for remote detection and recognition of objects outside the visual observation zone.

Known methods and devices for the remote detection of objects using non-linear methods and radar devices (NRL) [1, 2, 3], where the main elements of the devices are non-linear energy dissipators (HP) (high-frequency semiconductor radio components, point and planar metal parts contacts), available (or specially placed) in the search object.

When the search object is irradiated with a probing signal, the nonlinear scatterer re-emits the signal into space at the frequencies of higher harmonics and subharmonics of the probing signal.

Thus, the fact that a search engine records a response signal at higher harmonics and subharmonics of the probe signal indicates that there is a nonlinear scatterer or a nonlinear passive marker (NM) in the irradiation region.

Significant disadvantages of these methods and devices are the insignificant (up to 30 m) detection range of the search objects and poor noise immunity due to the small power conversion coefficient of the received probe signal into its higher harmonics and subharmonics signals (weak passive response signal), as well as the inability to identify (recognize ) search objects.

The use of HP in parametric diffusers [4, 5, 6], which increase the energy conversion efficiency of the input signal by one or two orders of magnitude, increases the power of the response signal, which slightly increases the detection range of search objects (less than 100 m) and noise immunity.

An increase in the HP detection range due to a significant increase in the power of the probe signal or the sensitivity of the search engine receiver leads to a deterioration in electromagnetic compatibility, an increase in danger to operators, and a decrease in noise immunity.

As a prototype of the invention, a technical solution [6] was selected, which can be used in search engines, for example, in a shipwreck victims detection system.

In the case of a distress signal, the search system emits into the space a probe signal received by the search object with HP, which excites in the nonlinear marker, a subharmonic parametric scatterer, oscillations at half the frequency of the probe signal radiated into space and received by the search system, which allows the search object to be detected in the direction Search engine receive antenna - its direction.

The prototype device consists of a search system located on a mobile water or air carrier and consisting of a probe signal generator connected to a radiating antenna, tuned to the probe signal frequency, a receiving antenna and a receiver connected to it, tuned to half the probe signal frequency, and non-linear marker located on the search object.

Non-linear marker - a subharmonic parametric scatterer consists of a receiving and transmitting antenna, tuned, respectively, to the frequency of the probing signal and its half frequency, and two parametric generators tuned to the half frequency of the probing signal.

A parametric generator is a parametric oscillatory circuit consisting of an inductance and an HP having a non-linear capacitance, which can be used as a semiconductor diode.

The disadvantages of the prototype are the same as for analogues, although the detection range and noise immunity of the prototype are slightly increased.

Achievable technical result of the present invention is a significant (one or two orders of magnitude) increase in the detection range of search objects with non-linear markers with increased noise immunity and the ability to recognize search objects.

An additional technical result is the ability to notify about the beginning of the search for an object.

In the proposed method, as in the prototype, the search system irradiates the search object containing a nonlinear diffuser with a probing signal at a frequency f ₀ and receives a response at a different frequency. However, in the proposed method, the probe signal and the response signal are encoded and decoded, and the nonlinear scatterer, unlike the prototype, converts the high-frequency energy of the received probe signal into constant voltage energy to include the active response signal at a frequency f ₀ + Δf, where Δ << f ₀ .

The proposed method can be implemented by a device that ensures the achievement of the specified technical result due to the fact that in the known device, consisting of a search system (PS) located on a movable medium and including an antenna (A), a transmitting device (PU), the output of which is connected to the input / output of the antenna, and the receiver (Pr), and a non-linear marker (NM) located on the object of search and including the antenna (A), a transmitting device (PU), the output of which is connected to the input / output of the antenna, and a non-linear diffuser (HP) , PS additionally includes a band-pass filter (PF) and an indicator (I), and the input of the PF is connected to input-output A, and the output through Pr is connected to the input And, and in the NM, a band-pass filter (PF) and a code packet decoder (DCT) are additionally introduced , key (C), battery (Ak) and indicator (I), and the PF input connected to input-output A, and the output to the first input of DCT and HP input, the output of which is connected to the second input of DCT, the output of which is connected to the first Cl input, a second input of Cl - yield Ak, and output - with inputs PU and I. Furthermore, PU PS and PD HM tuned to a frequency f _0, PU HM, PF C - the frequency f ₀ + Δf, where Δf << f _0, both the UE conditioners comprise code chips, comprises Pr code decoder chip, and both antennas are receiving and transmitting with a passband from f ₀ to f ₀ + Δf and interconnected yourself over the air.

The figure shows a structural diagram of the proposed device, where it is indicated:

1 - search engine (PS);

2 - non-linear marker (NM);

3 - transmitting device (PU);

4 - band-pass filter (PF);

5 - receiver (Pr);

6 - indicator (I);

7 - antenna (A);

8 - antenna (A);

9 - band-pass filter (PF);

10 - transmitting device (PU);

11 - indicator (I);

12 - nonlinear diffuser (HP);

13 - code parcel decoder (DCT);

14 - key (C);

15 - battery (Ak).

The device for remote detection and recognition of objects with non-linear markers consists of a search engine PS 1 located on a movable medium, including a transmitter PU 3, a bandpass filter PF 4, a receiver Pr 5, an indicator I 6 and an antenna A 7, and the input-output A 7 connected to the output of the PU 3 and the input of the PF 4, the output of which through Pr 5 is connected to the input And, and a non-linear marker NM 2 located on the search object, including the antenna A 8, the bandpass filter PF 9, the transmitting device PU 10, the indicator And 11, HP 12 non-linear diffuser, decryption OR code parcels DCT 13, key 14 and battery Ak 15, and the input-output A 8 is connected to the output of the PU 10 and the input of the PF 9, the output of which is connected to the first input of the DCT 13 and through HP 12 to the second input of the DCT 13, the first the input of Cl 14 is connected to the output of DCT 13, the second to the output of Ak 15, and the output to the inputs of PU 10 and I 11.

In this case, PU 3 and PF 9 are tuned to the frequency f ₀ , PU 13, PF 4 and Pr 5 to the frequency f ₀ + Δf, where Δf << f ₀ , PU 3 and PU 10 include code message generators, and Pr 5 - decoder code parcels, and A 7 and A 8 are transmitting and receiving with a bandwidth from f ₀ to f ₀ + Δf and are interconnected via a radio channel.

The device operates as follows.

PU 3 emits through A 7 a probe signal in the form of a code sequence of pulses with a carrier frequency f ₀ , which passes through A 8 and PF 9 to the input of HP 12 and the first input of DCT 13. HP 12 converts the energy of the received high-frequency sounding signal into DC voltage, supplied to the second input of DCT 13. DCT 13 in the presence of a supply voltage from HP 12 and a known code package from PF 9 connects Ak 15 through Cl 14 to PU 10 and I 11 (light diode). The inclusion of And 11 indicates the beginning of the search for the object.

PU 10 begins to generate a response code parcel at a frequency f ₀ + Δf, which through A 8 and A7 goes through PF 4 to Pr 5 and then to And 6. Indications And 6 contain information about the direction and distance of the search object and its recognition (by the response code premises or in terms of Δf, which for each object may be different).

Thus, the use in the proposed method and apparatus of HP as a converter of high-frequency energy of the received probe signal into constant voltage energy to generate a more powerful, active response signal due to the introduced PU 10, DCT 13 and Ak 15, encoding and decoding of the probe signal and the response signal, use two (instead of four as in the prototype) the receiving-transmitting antenna with bandwidth f ₀ + Δf, where Δf << f _0, allowed to increase the detection range of the search objects with nonlinearities E markers, enhance noise immunity of the method and apparatus, and also to provide detection search objects.

Information sources

1. G.N. Shcherbakov. The use of nonlinear radar for remote detection of small objects. Special equipment, 1999, No. 1, p. 34-39.

2. N.Yu. Babanov et al. On the use of the effect of nonlinear scattering of radio waves in the search for those in distress on water. Radio Engineering and Electronics, 2000, v. 45, No. 6, p. 676.

3. Non-linear radar. Collection of articles, part 2. Ed. A.A. Gorbacheva et al., Radio Engineering, 2006.

4. A.V. Ivanov et al. Parametric method for detecting objects with nonlinear scatterers. University News. Ser. Radio Electronics, 2003, No. 9-10, p. 11-16.

5. Non-linear passive marker - parametric diffuser. RF patent №2336538, G01S 13/74, publ. 10/20/2008, bull. No. 29.

6. Subharmonic parametric diffuser. RF patent No. 2495450, G01S 13/74, publ. 10/10/2013, bull. No. 28.

Claims (2)

1. A method for remote detection and recognition of objects with non-linear markers, which consists in irradiating the search object with a probe signal at the carrier frequency f ₀ and receiving a response at a different frequency, characterized in that the non-linear marker converts the high-frequency energy of the received probe signal into constant-voltage energy for inclusion powerful active response signal at a frequency f ₀ + Δf, where Δf << f ₀ , and the probing signal and the response signal are encoded and decoded. 2. A device for remote detection and recognition of objects with non-linear markers, consisting of a search system (PS) located on a movable medium and including an antenna (A), a transmitting device (PU), the output of which is connected to the input / output of the antenna, and a receiver (Pr ), and a non-linear marker (NM) located on the search object and including an antenna (A), a transmitting device (PU), the output of which is connected to the input / output of the antenna, and a non-linear diffuser (HP), characterized in that the PS is additionally introduced band-pass filter (PF ) and indicator (I), and the PF input is connected to input-output A, and the output is connected through Pr with input I, and the bandpass filter (PF), code parcel decoder (DCT), key (C), battery are additionally introduced into the NM (Ak) and indicator (I), and the PF input is connected to input-output A, and the output is connected to the first input of DCT and HP input, the output of which is connected to the second input of DCT, the output of which is connected to the first input of Cl, the second input of Cl - with the output Ak, and the output with the inputs of the controllers and I, while the control panels of the FS and PF NM are tuned to the frequency f ₀ , the control panels of the NM, PF PS and Pr are tuned to the frequency f ₀ + Δf, where Δf << f ₀ , both controllers contain code parcel shapers, Pr contains a code parcel decoder, and both antennas are transmit-receive antennas with a bandwidth from f ₀ to f ₀ + Δf and are interconnected via a radio channel.

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