Quantum radar detection system based on quantum correlation

Abstract

The utility model discloses a quantum radar detection system based on quantum correlation. The quantum radar detection system comprises a signal generation module, a beam splitter a, a signal transmission module, a beam splitter b, an imaging device, an interference module, a detector and a master control module. The utility model discloses a quantum radar detection system based on quantum correlation, which is characterized in that a signal generation module outputs adjacent continuous pulses with good quantum correlation, when two continuous strong pulses enter an interference module, the two continuous strong pulses are completely coherent and cancelled, and a detector does not have a count value; external operation (such as interception and retransmission) can destroy quantum correlation, so that the interference module cannot output completely coherent and cancelled optical signals, and then the detector is triggered to generate a great count value; therefore, whether the detection signal of the quantum radar is interfered can be judged through the counting result of the detector, the judgment mode is simple and convenient, the error rate is greatly reduced, and the method is widely applied to the unmanned system and navigation field.

Description

TECHNICAL FIELD

[0001] The utility model relates to quantum radar and unmanned system technical field, concretely relates to a quantum radar detection system based on quantum correlation. BACKGROUND

[0002] Quantum radar (QR) is a new type of radar based on the basic principles of quantum mechanics, mainly relying on the transmission and reception of quantum signals to achieve target detection, using photons to image the target, as any object will change its quantum characteristics after receiving the photon signal, this kind of radar can detect stealth aircraft, and is almost undisturbed.

[0003] The existing quantum radar scheme as shown in the figure, including laser, acoustooptic modulator, half wave plate, filter, polarization beam splitter and imaging device. Figure 1 Its working principle is as follows: (1) the laser output by the laser is modulated by the acoustooptic modulator to generate a pulse sequence with an average photon number of 1;(2) the signal output by the acoustooptic modulator is further polarized to four polarization states: horizontal polarization (H), vertical polarization (V), diagonal polarization (D) and anti-diagonal polarization (A) by the half wave plate a;Then the laser from the half wave plate a is aligned to the target object;(3) the light signal reflected by the target object first passes through the filter, and then the noise is filtered out;(4) the half wave plate b and the polarization beam splitter constitute a polarization measurement device to measure the received light pulse;When the half wave plate b and the vertical polarization direction are parallel, the measurement light pulse is in horizontal polarization state or vertical polarization state;When the half wave plate b and the vertical polarization direction form an angle of 22.5°, the measurement light pulse is in diagonal anti-polarization state or diagonal polarization state;(5) two imaging devices are placed on both sides of the polarization beam splitter, which are used for imaging of different polarized light pulses. This scheme is completed according to the BB84 protocol in quantum key distribution. When the polarization of the reflected photon and the incident one has more than 25% error rate, it can be determined that the target is disturbed.

[0004] However, the polarization of light will change significantly after being scattered by the object (non-specular surface), which will cause the existing quantum radar to have a large error rate without any disturbance, and thus the detection result has a large error, making it difficult to accurately determine whether the detection signal is disturbed. Utility model content

[0005] The utility model discloses a quantum radar detection system based on quantum correlation to solve the problem that the existing quantum radar is difficult to accurately determine whether the detection signal is disturbed.

[0006] To achieve the above purpose, the technical scheme adopted by the utility model is as follows:

[0007] A quantum radar detection system based on quantum correlation, comprising a signal generation module, a beam splitter a, a signal transmission module, a beam splitter b, an imaging device, an interference module, a detector and a master control module;

[0008] The signal generation module comprises a first signal generation module and a second signal generation module;

[0009] The signal transmission module comprises a transmitting waveguide module and a receiving waveguide module;

[0010] The output end of the first signal generation module and the output end of the second signal generation module are respectively connected with the input end of the transmitting waveguide module through the beam splitter a, the detection signal output by the transmitting waveguide module is reflected after encountering a target object and is received by the receiving waveguide module, the output end of the receiving waveguide module is connected with the input end of the imaging device and the input end of the interference module through the beam splitter b, the output end of the interference module is connected with the input end of the detector, and the output end of the imaging device and the output end of the detector are respectively connected with different input ends of the master control module.

[0011] In the above scheme, the signal generation module outputs adjacent continuous pulses with good quantum correlation, when two continuous strong pulses enter the interference module, they will completely destructively interfere, so the detector will not have a count value; external operations (such as interception and retransmission) will destroy the quantum correlation, so that the interference module cannot output completely coherent and destructive light signals, thereby triggering the detector to have a large count value; therefore, whether the detection signal of the quantum radar is disturbed can be judged by the count result of the detector, the discrimination method is simple, and the error rate is greatly reduced; and the pulses output by the signal generation module contain multiple photons, thereby greatly improving the detection distance.

[0012] Preferably, the first signal generation module comprises a laser a and an adjustable attenuator a;

[0013] The output end of the laser a is connected with the input end of the adjustable attenuator a, and the output end of the adjustable attenuator a is connected with the first port of the beam splitter a.

[0014] Preferably, the second signal generation module comprises a laser b and an adjustable attenuator b;

[0015] The output end of the laser b is connected with the input end of the adjustable attenuator b, and the output end of the adjustable attenuator b is connected with the second port of the beam splitter a.

[0016] Preferably, the signal transmission module further comprises a lens and a scanning module;

[0017] The probe signal output by the transmitting waveguide module is transmitted to the scanning module through the lens, and the probe target object is output by the scanning module; the probe signal reflected by the target object is sequentially input into the receiving waveguide module after passing through the scanning module and the lens.

[0018] Preferably, the signal transmission module further comprises a filter piece.

[0019] The output end of the receiving waveguide module is connected with the first port of the beam splitter b through the filter piece.

[0020] Preferably, the scanning module is a scanning galvanometer or a scanning rotating mirror.

[0021] Preferably, the interference module is an unequal arm interference module.

[0022] Preferably, the unequal arm interference module comprises a beam splitter c, a phase modulator a, a phase modulator b and a beam splitter d.

[0023] The second port of the beam splitter b is connected with the input end of the imaging device, the third port of the beam splitter b is connected with the first port of the beam splitter c, the second port of the beam splitter c is connected with the first port of the beam splitter d through the phase modulator a, the third port of the beam splitter c is connected with the second port of the beam splitter d through the phase modulator b, and the third port of the beam splitter d is connected with the input end of the detector.

[0024] Preferably, the beam splitter b is a 50:50 beam splitter.

[0025] Preferably, the master control module is an FPGA master control module.

[0026] The beneficial technical effects of the utility model are as follows:

[0027] The utility model discloses a quantum radar detection system based on quantum association, and the adjacent continuous pulse with good quantum association is output through the signal generation module, when two continuous strong pulses enter the interference module, will completely coherent cancellation, and the detector will not have the count value, and the external operation (such as interception and retransmission) will destroy quantum association, make the interference module output not completely coherent cancellation light signal, and then trigger the detector to appear the great count value, therefore, whether the detection signal of quantum radar is interfered can be judged through the count result of the detector, and the discrimination mode is simple, greatly reduces the error rate, and the pulse output by the signal generation module contains multiple photons, and then the detection distance has greatly improved, and is widely applied to unmanned system and navigation field. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is the existing quantum radar structure schematic diagram;

[0029] Figure 2The utility model discloses a whole structure schematic diagram. DETAILED DESCRIPTION

[0030] In order to make the utility model's purpose, technical scheme and advantage more clearly, the following with example to the utility model carries out further detailed explanation, but the utility model's scope of protection is not limited to the following specific embodiment.

[0031] Embodiment 1

[0032] As Figure 1 The utility model discloses a quantum radar detection system based on quantum correlation, including signal generating module, beam splitter a, signal transmission module, beam splitter b, imaging device, interference module, detector and main control module.

[0033] The signal generating module includes first signal generating module and second signal generating module.

[0034] The signal transmission module includes transmitting waveguide module and receiving waveguide module.

[0035] The output of first signal generating module, the output of second signal generating module are connected with the input of transmitting waveguide module through beam splitter a respectively, and the detection signal that the output of transmitting waveguide module meets target object is reflected and is received by receiving waveguide module, and the output of receiving waveguide module is connected with the input of imaging device, the input of interference module through beam splitter b respectively, and the output of interference module is connected with the input of detector, and the output of imaging device, the output of detector are connected with different input of main control module respectively.

[0036] In the specific implementation process, the adjacent continuous pulse with good quantum correlation is output through the signal generating module, when two continuous strong pulses enter the interference module, will be completely coherent destructive interference, then the detector will not have the count value, and the external operation (such as interception and retransmission) will destroy the quantum correlation, so that the interference module can not output completely coherent destructive interference light signal, and then trigger the detector to appear the great count value, so that the count result of the detector can judge whether the detection signal of the quantum radar is disturbed, the discrimination mode is simple, and the error rate is greatly reduced, and the pulse output by the signal generating module contains multiple photons, so that the detection distance is greatly improved.

[0037] Embodiment 2

[0038] As Figure 2 The utility model discloses a quantum radar detection system based on quantum correlation, including signal generating module, beam splitter a, signal transmission module, beam splitter b, imaging device, interference module, detector and main control module.

[0039] The signal generation module comprises a first signal generation module and a second signal generation module;

[0040] More specifically, the beam splitter b is a 50:50 beam splitter;

[0041] More specifically, the master control module is an FPGA master control module;

[0042] In the specific implementation process, the FPGA master control module is used, the operability is enhanced, the circuit of the whole system is more concise, and the stability is greatly improved.

[0043] More specifically, the first signal generation module comprises a laser a and an adjustable attenuator a;

[0044] The output end of the laser a is connected with the input end of the adjustable attenuator a, and the output end of the adjustable attenuator a is connected with the first port of the beam splitter a.

[0045] More specifically, the second signal generation module comprises a laser b and an adjustable attenuator b;

[0046] The output end of the laser b is connected with the input end of the adjustable attenuator b, and the output end of the adjustable attenuator b is connected with the second port of the beam splitter a.

[0047] In the specific implementation process, the laser a and the laser b output laser with the same frequency as the trigger signal according to the trigger signal given by the FPGA master control module, wherein:

[0048] 1. The trigger signal of the laser a should be MHz order, the trigger signal of the laser b should be kHz order, and the trigger frequencies of the laser a and the laser b should be more than 1000 times different;

[0049] 2. The wavelengths of the laser a and the laser b are the same, and the wavelengths can be 1550nm, 1570nm, 1330nm and other wavelengths;

[0050] 3. There is a time interval between the trigger signal pulse of the laser a and the trigger signal pulse of the laser b;

[0051] The light emitted by the laser a and the laser b respectively passes through the adjustable attenuator a and the adjustable attenuator b for intensity adjustment, so as to make the light with multiple photons and the same intensity output from the adjustable attenuator a, and the light with weak pulse and the number of photons close to 0 output from the adjustable attenuator b, which is equivalent to a vacuum state; wherein the attenuation values of the adjustable attenuator a and the adjustable attenuator b can be adjusted and controlled through the FPGA master control module.

[0052] The light output from the adjustable attenuator a and the adjustable attenuator b passes through the beam splitter a and is synthesized into one path and output; the light output from the beam splitter a contains a plurality of photon strong pulses and almost no photon weak pulses, and the pulse sequence formed by the two pulses serves as a quantum radar detection signal.

[0053] The signal transmission module comprises a transmitting waveguide module and a receiving waveguide module.

[0054] More specifically, the signal transmission module further comprises a lens and a scanning module.

[0055] More specifically, the scanning module is a scanning galvanometer or a scanning rotating mirror.

[0056] In the specific implementation process, the scanning module can comprise any optical device capable of changing the light propagation path, such as a galvanometer or a rotating mirror, so that the quantum radar detection signal can be output at different angles to achieve detection of the target object at different angles.

[0057] More specifically, the signal transmission module further comprises a filter.

[0058] The third port of the beam splitter a is connected with the input end of the transmitting waveguide module, the detection signal output from the transmitting waveguide module is transmitted to the scanning module through the lens, and the target object is detected by the scanning module; the detection signal reflected by the target object is input into the receiving waveguide module in sequence through the scanning module and the lens.

[0059] The output end of the receiving waveguide module is connected with the first port of the beam splitter b through the filter.

[0060] In the specific implementation process, in order to keep the optical signal at a low loss during transmission, the optical signal output from the beam splitter a is transmitted to the lens through the transmitting waveguide module as the quantum radar detection signal, so that the quantum radar detection signal can be accurately transmitted to the scanning module through the lens, and the quantum radar detection signal output from the scanning module is reflected after encountering the target object; the reflected signal is transmitted to the lens through the scanning module, and the optical signal reflected by the target object can be accurately transmitted to the receiving waveguide module through the effective focusing beam of the lens, so that the optical signal reflected by the target object can be transmitted through the receiving waveguide module at a low loss; the light output from the receiving waveguide module passes through the filter, so that other noise signals are filtered out and only the light of the same wavelength as the quantum radar detection signal is retained. The filter effectively improves the anti-interference performance, and the filter structure is simple and low in cost.

[0061] More specifically, the interference module is an unequal-arm interference module.

[0062] More specifically, the unequal-arm interference module comprises a beam splitter c, a phase modulator a, a phase modulator b and a beam splitter d;

[0063] The second port of the beam splitter b is connected with the input end of the imaging device, the third port of the beam splitter b is connected with the first port of the beam splitter c, the second port of the beam splitter c is connected with the first port of the beam splitter d through the phase modulator a, the third port of the beam splitter c is connected with the second port of the beam splitter d through the phase modulator b, and the third port of the beam splitter d is connected with the input end of the detector.

[0064] In the specific implementation process, the light signal output from the filter is equally divided by 50:50 through the beam splitter b, and two equal light signals are output; one of the light signals is transmitted to the imaging device for imaging, and the imaging device outputs the imaging information to the FPGA main control module, and then the FPGA main control module processes the imaging information; the other light is transmitted to the beam splitter c;

[0065] The input light signal is equally divided by 50:50 by the beam splitter c, so that two equal light signals are output and enter the phase modulator a and the phase modulator b for phase modulation, respectively. The phase modulation of the two light signals is to make the pulse time delay and the time interval between the pulses of the two signals the same; in this way, the light signals output from the phase modulator a and the phase modulator b are input to the beam splitter d, and then interference is formed, so that the beam splitter d can output coherent and destructive light signals. The phase modulator a and the phase modulator b can be adjusted and controlled by the FPGA main control module.

[0066] In the specific implementation process, whether the detection signal of the quantum radar is disturbed is determined by the counting result of the detector, and the principle is derived from quantum correlation; adjacent continuous pulses of laser output by the laser have good quantum correlation, so that when two continuous strong pulses enter the unequal-arm interference module, they will be completely coherent and destructive, that is, the beam splitter d will output completely coherent and destructive light signals, and the completely coherent and destructive light signals entering the detector will not be triggered, that is, the detector will not have a counting value.

[0067] When external operations (such as interception and retransmission) occur, the quantum correlation will be destroyed, so that the interferometer cannot output completely coherent and destructive light signals, and thus the detector is triggered, so that the detector has a very large counting value. By comparing the emitted light signal and the received light signal, and the counting result of the detector, it can be known that the quantum correlation in the echo pulse sequence is destroyed.

[0068] Therefore, once the situation that the detector has a very large counting value or the counting value of the detector is much larger than the dark count occurs, it can be determined that there is a disturbance signal in the echo signal

[0069] According to the disclosure and teaching of the above description, the skilled in the art of the present application can also change and modify the above embodiments. Therefore, the present application is not limited to the specific embodiments disclosed and described above, and some modifications and changes of the present application should fall within the protection scope of the claims of the present application. In addition, although some specific terms are used in the specification, these terms are only for convenience and do not constitute any limitation on the present application.

Claims

1. A quantum radar detection system based on quantum correlations, characterized in that, The signal generation module, a beam splitter a, a signal transmission module, a beam splitter b, an imaging device, an interference module, a detector and a master control module are included. The signal generation module includes a first signal generation module and a second signal generation module. The signal transmission module includes a transmitting waveguide module and a receiving waveguide module. The output end of the first signal generation module and the output end of the second signal generation module are respectively connected with the input end of the transmitting waveguide module through the beam splitter a, the detection signal output by the transmitting waveguide module is reflected after encountering the target object and is received by the receiving waveguide module, the output end of the receiving waveguide module is connected with the input end of the imaging device and the input end of the interference module through the beam splitter b, the output end of the interference module is connected with the input end of the detector, and the output end of the imaging device and the output end of the detector are respectively connected with different input ends of the master control module.

2. The quantum radar system based on quantum correlations according to claim 1, characterized in that, The first signal generation module includes a laser a and an adjustable attenuator a. The output end of the laser a is connected with the input end of the adjustable attenuator a, and the output end of the adjustable attenuator a is connected with the first port of the beam splitter a.

3. The quantum correlation based quantum radar detection system of claim 1, wherein, The second signal generation module includes a laser b and an adjustable attenuator b. The output end of the laser b is connected with the input end of the adjustable attenuator b, and the output end of the adjustable attenuator b is connected with the second port of the beam splitter a.

4. The quantum correlation based quantum radar detection system of claim 1, wherein, The signal transmission module further includes a lens and a scanning module; The detection signal output by the transmitting waveguide module is transmitted to the scanning module through the lens, and the target object is output by the scanning module; the detection signal reflected by the target object is input into the receiving waveguide module in sequence after passing through the scanning module and the lens.

5. The quantum correlation based quantum radar detection system of claim 1, wherein, The signal transmission module further includes a filter; The output end of the receiving waveguide module is connected with the first port of the beam splitter b through the filter.

6. The quantum radar system based on quantum correlations according to claim 4, characterized in that, The scanning module is a scanning galvanometer or a scanning rotating mirror.

7. The quantum correlation based quantum radar detection system of claim 1, wherein, The interference module is an unequal-arm interference module.

8. The quantum radar system based on quantum correlations according to claim 7, characterized in that, The unequal-arm interference module includes a beam splitter c, a phase modulator a, a phase modulator b and a beam splitter d. The second port of the beam splitter b is connected with the input end of the imaging device, the third port of the beam splitter b is connected with the first port of the beam splitter c, the second port of the beam splitter c is connected with the first port of the beam splitter d through the phase modulator a, the third port of the beam splitter c is connected with the second port of the beam splitter d through the phase modulator b, and the third port of the beam splitter d is connected with the input end of the detector.

9. The quantum correlation based quantum radar detection system of claim 1, wherein, The beam splitter b is a 50:50 beam splitter.

10. The quantum correlation based quantum radar detection system of claim 1, wherein, The master control module is an FPGA master control module.

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