Quantum ranging type positioning device and method based on microwave and light entanglement

Abstract

The invention discloses a quantum distance measurement type positioning device and method based on microwave and light entanglement, and the method comprises the steps: firstly analyzing the relation between a quantum second-order coherence function and a transmission coefficient eta when analyzing the performance of a quantum distance measurement type positioning scheme, and obtaining a quantum distance measurement type positioning precision histogram of different transmission coefficients; according to error characteristics in quantum distance measurement type positioning, error area characteristics determined by the scheme are directly analyzed, the spatial distribution condition of positioning errors in a working area is obtained, the spatial distribution condition is compared with a positioning error field used by classical geometric positioning, and finally the performance of the scheme in dynamic trajectory tracking of a target is analyzed. The quantum distance measurement type positioning method provided by the invention has relatively high effectiveness and accuracy, and can be applied to the fields of navigation, radar and the like as a new positioning method.

Description

[Technical field]

[0001] The present invention relates to a quantum distance measurement positioning device and method, and in particular to a quantum distance measurement positioning device and method based on microwave and light entanglement. [Background technology]

[0002] Positioning is a method for studying how to effectively provide the real-time location of a target. It is not only a basic task of navigation activities, but is also widely studied in the fields of radar, surveying and mapping. Although the positioning systems studied in different research fields differ in service objects, methods and means, and performance, their fundamental research connotations are consistent, that is, how to obtain target location information. However, due to its own reasons, the existing quantum positioning method has insufficient positioning accuracy. In view of this, the present invention provides a quantum ranging positioning device and method based on microwave and light entanglement. [Summary of the invention]

[0003] In order to solve the above problems, the present invention provides a quantum ranging positioning device and method based on microwave and light entanglement.

[0004] The present invention is implemented by the following technical solutions, and provides a quantum ranging positioning device based on microwave and light entanglement, including:

[0005] There are two ground base stations, each of which is composed of two cavity electro-optical converters, one of which is the transmitting end and the other is the receiving end. The transmitting end in each ground base station is used to prepare hybrid microwave-light wave entanglement, while the receiving end is used to receive the returned microwave signal and perform frequency band shifting and quantum state transfer on it.

[0006] In particular, the cavity frequency detuning amount of the transmitting end is set to Δ M =-Δ O =ω m , the cavity frequency detuning amount of the receiving end is set to Δ M =Δ O =ω m .

[0007] The present invention also provides a quantum ranging positioning device method based on microwave and light entanglement, comprising the following steps:

[0008] S1 marks one of the two ground base stations as G 1 , and the other is labeled G 2 , G 1 The transmitting end and receiving end in the example are denoted as A and B respectively, and G 2 The transmitting end and receiving end in the above example are denoted as A' and B'. A and A' are ground stations that prepare microwave-light wave entanglement and output microwaves. Transmitted into free space, the light wave is output It is stored locally and waits for the coincidence detection with the light wave signal output by the receiving end. Each output signal can be expressed as

[0009]

[0010]

[0011]

[0012]

[0013] In formulas (1)-(4), A and A' are the thermal noise microwave photons, optical frequency photons and thermally excited phonons of mechanical oscillators in the cavity, respectively. M , Ao, B, C M , Co factors can be determined by the coordination parameter Γ j Indicates, as follows:

[0014]

[0015]

[0016]

[0017]

[0018]

[0019] The synergy parameters in formulas (101)-(105) are expressed as follows:

[0020]

[0021] In formula (106), κ M , κ O and γ are the dissipation rates corresponding to microwave cavity mode, light wave cavity mode and mechanical resonance mode, G j is the overall coupling rate between the cavity mode and the mechanical resonant mode;

[0022] S2 Since microwave signals are damaged and affected by noise during free space transmission, a beam splitter model is established for each microwave signal. The corresponding transmission coefficients in the beam splitter model are η 1 , η 2 When the microwave signal encounters the target, part of the microwave signal is absorbed by the target surface, and part is reflected and received by the receiving antenna of the ground station. The return microwave signals of the two ground stations are recorded as Assume the ambient temperature is T B, the background noise is recorded as The average number of photons is Therefore, the return microwave signal can be expressed by the following formulas according to the relationship of the beam splitter:

[0023]

[0024]

[0025] After the returned microwave signal is received, the receiving end conjugates it and converts it into a light wave signal output. The output light wave signal can be expressed as follows:

[0026]

[0027]

[0028] In the above formula, the receiver The transmitter The corresponding amount of

[0029] S3 After being output, they are stored in the local Perform a correlation test to obtain The corresponding second-order coherence functions are as follows:

[0030]

[0031]

[0032] In formulas (9) and (10), and Respectively and The photon number operator, τ 1 and τ 2 G 1 and G 2 The one-way transmission delay of the transmitted microwave signal in free space and the maximum value of the second-order coherence function of the entangled state are expressed by the following formula:

[0033]

[0034] In formula (11), δ is the signal spectrum width, τ is the one-way transmission delay of the microwave signal in free space,

[0035] After obtaining the maximum value of the second-order coherence function, the one-way transmission delay τ can be further obtained. 1 and τ 2 ;

[0036] S4 According to the one-way transmission delay and the propagation speed of microwave signals in free space, the distance between the two ground stations and the target can be calculated using the following formula:

[0037] d 1 =cτ 1 (12)

[0038] d 2 =cτ 2 (13)

[0039] In formulas (12) and (13), c is the propagation speed of microwave signals in free space, which is 3×10 8 m / s. Since microwave transmission delay has a certain measurement error, and the timing error here can be represented by the half-height full width of the second-order coherence function, the timing accuracy Δτ and ranging accuracy are shown in the following formula:

[0040]

[0041] Δd=cΔτ (02)

[0042] In formulas (01) and (02), They represent the two time points corresponding to the half-height values, so the precise distance between the ground station and the target is expressed by the following formula:

[0043] D=d+cΔτ (03)

[0044] In formula (03), d is the distance between the two ground stations and the target, which is the rough distance;

[0045] After measuring the precise distance, two circles are obtained with the two ground stations as the center and the measured distance as the radius, and the intersection of the two circles is obtained. If the two circles have only one intersection, then the intersection is the target position; if there are two intersections, one of them is the image of the target position relative to the baseline. The image point can be removed according to the direction of the ground station's transmitted and received signals or other judgment criteria to determine the target position.

[0046] Compared with the existing design, the present invention provides a quantum ranging positioning device and method based on microwave and light entanglement. Firstly, the relationship between the quantum second-order coherence function and the transmission coefficient is analyzed, and a quantum ranging positioning accuracy bar chart under different transmission coefficient pairs is obtained. Then, according to the error characteristics in quantum ranging positioning, the error area characteristics determined by the scheme are directly analyzed to obtain the spatial distribution of the positioning error in the working area, and compared with the positioning error field used in classical geometric positioning. Finally, the performance of the scheme in dynamic trajectory tracking of the target is analyzed.

Brief Description of the Drawings

[0047] Figure 1 This is a schematic diagram of the structure of a quantum ranging positioning device;

[0048] Figure 2 It is a schematic diagram of the structure of a ground base station;

[0049] Figure 3 This is a schematic diagram of the error area of ​​the quantum ranging positioning solution;

[0050] Figure 4 is the second-order coherence function g under different transmission coefficients η (2) (2τ) and its waterfall plot;

[0051] Figure 5 For different transmission coefficient combinations (η 1 ,η 2 ) under the positioning error distribution;

[0052] Figure 6 is the circular position line error characteristic in the classic ranging scheme;

[0053] Figure 7 Comparison of error field distribution diagrams between quantum ranging positioning scheme and classical geometric ranging positioning scheme;

[0054] Figure 8 is η 1 =η 2 = 0.5, the actual trajectory and the trajectory obtained by the quantum ranging positioning scheme;

[0055] Fig. 9 is η 2 =0.6 and the trajectory obtained by the quantum ranging positioning scheme. [Specific implementation method]

[0056] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings.

[0057] The present invention provides a quantum ranging positioning device based on microwave and light entanglement. By adopting a cavity electro-optical force converter and the microwave-light wave hybrid entangled signal prepared therefrom, high-precision transmission delay measurement can be achieved, thereby obtaining the precise distance between the ground station and the target. If two identical ground stations simultaneously perform precise distance measurement on the target, and the baseline distance between the two ground stations is known, the precise position information of the target in the two-dimensional plane can be obtained through circle-to-circle positioning. Different from other quantum positioning schemes, the spatial transmission signal of this scheme is microwave, and the detection signal is light wave. The physical basis it relies on is the microwave-light wave hybrid entanglement characteristics. It is a new quantum positioning method, and its principle is as follows: Figure 1 As shown in Figure 2, the composition of each ground station is as follows: Figure 2shown.

[0058] like Figure 1 As shown, the quantum positioning scheme proposed in the present invention includes two ground stations with the same structure, and it is assumed that the target and the ground station have achieved time synchronization. Figure 2 As can be seen in the figure, each ground station consists of two cavity electro-optical converters, one of which is the transmitter and the other is the receiver, which is the same as the ranging scheme in Chapter 5. Therefore, the transmitter is used to prepare hybrid microwave-light wave entanglement (Δ M =-Δ O =ω m ), and the receiving end is used to receive the returned microwave signal and perform frequency band transfer and quantum state transfer (Δ M =Δ O =ω m The two ground stations are respectively 1 and G 2 Mark G 1 The transmitting end and receiving end in the example are denoted as A and B respectively, and G 2 The transmitting end and receiving end in the above are denoted as A' and B'. A and A' prepare microwave-light wave entanglement for their respective ground stations and output microwaves Transmitted into free space, the light wave is output It is stored locally and waits for the coincidence detection with the light wave signal output by the receiving end. Each output signal can be expressed as

[0059]

[0060]

[0061]

[0062]

[0063] The beam splitter model is still considered for analyzing the loss and noise effects of microwave signals during free space transmission. The losses in the transmission process (atmospheric attenuation, material absorption, scattering, etc.) are uniformly characterized by the transmission coefficient of the beam splitter model, and noise is considered as another input of the beam splitter model. Since the distance between each ground station and the target is not necessarily the same, the transmission distance, environmental loss, etc. of each microwave signal are not necessarily the same. Therefore, it is necessary to establish a beam splitter model for each microwave signal. The corresponding transmission coefficients in the beam splitter model are η 1 , η 2 When the microwave signal encounters the target, part of the microwave signal is absorbed by the target surface, and part is reflected and received by the receiving antenna of the ground station. The return microwave signals of the two ground stations are recorded as Assume the ambient temperature is T B , the background noise is recorded as Its average number of photons Therefore, the return microwave signal can be expressed as

[0064]

[0065]

[0066] After the return microwave signal is received, the receiving end conjugates it and converts it into a light wave signal for output. The output light wave signal can be expressed as

[0067]

[0068]

[0069] Among them, the receiving end The transmitter The corresponding amount.

[0070] Once exported, they are immediately synchronized with the local data stored in the respective ground stations. If the correlation test is performed, we can obtain The corresponding second-order coherence functions are

[0071]

[0072]

[0073] in, and Respectively and The photon number operator, τ 1 and τ 2 It's G 1 and G 2 The one-way transmission delay of the transmitted microwave signal in free space. At the same time, the maximum value of the second-order coherence function of the entangled state is expressed by the following formula:

[0074]

[0075] Among them, δ is the signal spectrum width. Therefore, if the maximum value of the second-order coherence function is obtained, the one-way transmission delay τ can be further obtained 1 and τ 2 . G 1 , G 2 The rough distance obtained is

[0076] d 1 =cτ 1(12)

[0077] d 2 =cτ 2 (13)

[0078] Where c is the propagation speed of microwave signal in free space, which is 3×10 8 m / s. In formulas (12) and (13), c is the propagation speed of microwave signals in free space, which is 3×10 8 m / s. Since microwave transmission delay has a certain measurement error, and the timing error here can be represented by the half-height full width of the second-order coherence function, the timing accuracy Δτ and ranging accuracy are shown in the following formula:

[0079]

[0080] Δd=cΔτ (02)

[0081] In formulas (01) and (02), They represent the two time points corresponding to the half-height values, so the precise distance between the ground station and the target is expressed by the following formula:

[0082] D = d + cΔτ (03);

[0083] After the precise distance between the two ground stations and the target is obtained, two circles can be obtained by taking the two ground stations as the center and the measured distance as the radius, and the intersection of the two circles can be obtained. If the two circles have only one intersection, then the intersection is the target position; if there are two intersections, one of them is the image of the target position relative to the baseline, and the image point can be removed according to the direction of the ground station's transmission and reception signals or other judgment criteria to determine the target position.

[0084] In order to quantitatively analyze the performance of the present invention, reasonable parameter settings are first required. The settings of some common parameter values ​​of each cavity electro-optical force converter are shown in Table 1.

[0085] Table 1. Relevant parameter settings of cavity electro-optical force converter

[0086]

[0087] At the same time, the quality factor Q of the cavity electro-optical force converter and the mass m of the mechanical oscillator are set to 30×10 3 and 10ng, the cavity length l of the optical cavity is set to 1μm, and the spectrum line width is set to δ=100MHz. For environmental factors, corresponding parameters are also set: the free space background temperature is set to T B = 293K, the operating temperature of the cavity electro-optical force converter is set to T E =30mK.

[0088] In order to further verify the quantum positioning performance of the present invention, the performance of the quantum positioning scheme is analyzed as follows.

[0089] 1.1 Positioning Accuracy

[0090] The loss of microwave signals in free space is characterized by the transmission coefficient η of the beam splitter model. Since the absorption and scattering characteristics of the target are fixed, the loss caused is also relatively fixed. If the free space transmission channel is regarded as a uniform channel, the loss caused is proportional to the transmission distance. This means that the effect of different distances on the signal can be simulated by changing the value of the transmission coefficient η. Obviously, a larger transmission coefficient means lower loss and a shorter transmission distance.

[0091] If the target is connected to two ground stations G 1 , G 2 If the distance between the two circles can be obtained completely accurately, the corresponding distance value can be used as the radius to get the exact intersection of the two circles, and then the exact position of the target can be calculated. This ideal situation can be obtained by Figure 3 However, it is impossible to measure the corresponding distance value completely accurately in practice. The distance error will cause the radius value to have a certain floating range, which will eventually lead to a certain error in the positioning of the target, that is, the target position degenerates from an accurate point to a possible range. Figure 3 The dotted lines in the figure represent the upper and lower limits of the radius of the corresponding circle, and the bright yellow part is the range where the target is located, which reflects the positioning error of the solution.

[0092] From the above analysis, it can be seen that the ranging error comes from the transmission delay measurement error, which can be quantified by the half-maximum full width value of the second-order coherence function. The second-order coherence function reflects the characteristics of hybrid entanglement. Therefore, the performance of the present invention is also determined by the entanglement characteristics.

[0093] Assume that η 1 =η 2 = 0.5, which means that the distances from the two stations to the target are the same, and the target is located on the perpendicular bisector of the baselines of the two stations. At this time, the transmission delay can be obtained by equations (9), (10), and (11) as 2τ 1 =2τ 2 =5.3451μs, the corresponding rough distance can be calculated by equations (11) and (12) as d 1 =d 2 =801.7650m. Further analysis of the second-order coherence function can yield its half-maximum full width value, i.e., the transmission delay measurement error, which is

[0094]

[0095] The corresponding ranging error is

[0096] Δd 1 =Δd 2 =cΔτ 1 =8×10 -4 m (15)

[0097] Depend on Figure 3 As shown in Figure 2, the positioning error of the solution can be quantified by the area of ​​the bright yellow region. If it is approximately regarded as a rectangle, the positioning error can be obtained as

[0098] E=|Δd 1 |×|Δd 2 |=6.4×10 -7 m 2 (16)

[0099] It can be seen from formula (16) that although the positioning error of the present invention also originates from the transmission delay error, it is different from the linear relationship between the ranging error and the timing error. The positioning error and the timing error are in a second-order moment relationship. Considering the size of the range between the target and the ground station at this time, such a small positioning error can be almost ignored. This shows that the present invention has a high theoretical positioning accuracy.

[0100] The above analysis is based on η 1 =η 2 = 0.5, but in fact η 1 and η 2 In most cases, they are different. Therefore, it is necessary to further analyze the impact of different η on the performance of the solution. The second-order coherence function graph and its corresponding waterfall graph corresponding to different η are as follows: Figure 4 As shown in (a) and (b).

[0101] Depend on Figure 4 It can be clearly seen that a smaller η corresponds to a smaller From equations (11), (12), and (13), we can see that the smaller This means a longer transmission delay and a longer distance. Figure 4 It can also be seen that g (2) The half-width of (2τ) widens as η decreases. From equation (14), we can see that this means a larger transmission delay measurement error Δτ. Of course, Figure 4 It is also clear that the spread of the half-height full width value is always small. Therefore, the greater the distance between the target and the ground station, the greater the corresponding transmission delay measurement error, and the ranging error increases linearly. Figure 4 It shows that the performance degradation caused by the distance change is small. Since the positioning error is not a simple linear relationship with the timing or distance measurement error, the discussion of the positioning error requires a comprehensive consideration of the results measured by the two ground stations. 1 , η 2The changes in Figure 5 The bar graph shown is described.

[0102] In the right Figure 4 After discussion, we found that smaller η corresponds to smaller Smaller This means a longer transmission delay and a longer distance. Figure 5 It can be further inferred that when one transmission coefficient is fixed and the other transmission coefficient changes, the positioning error increases with the decrease of the transmission coefficient, and it is a linear increase; when both transmission coefficients increase, the positioning error will definitely increase, and it is a nonlinear increase; when one transmission coefficient increases and the other transmission coefficient decreases, the change of the positioning error is uncertain, which is related to the product of the ranging errors of the two ground stations.

[0103] 1.2 Distribution of quantum positioning errors

[0104] In geometric navigation positioning, the positioning error field is often used to analyze the positioning error distribution. The positioning error field can start from the statistical characteristics of relevant navigation parameters (such as distance), analyze its variance or mean square error, and thus obtain the maximum and minimum values ​​of the error distribution at a specific point and the corresponding direction, and draw its distribution in the form of an equal probability error ellipse. The distribution of the equal probability error ellipse in the working area constitutes the positioning error field.

[0105] In the geometric positioning process based on the classic ranging scheme, the two ground stations can obtain their respective circular position lines through ranging, and then achieve circle-circle positioning. The positioning error at this time comes from the circular position line error, that is, the ranging error. The circular position line error characteristics in the classic ranging scheme are as follows: Figure 6 shown.

[0106] from Figure 6 It can be seen from the figure that the circular position line error in the classic ranging scheme does not change with the change of distance, and the circular position line error of a specific ground station is constant, that is, P i P i ′=Δd.

[0107] When the circular position line errors of the two ground stations obey the zero-mean Gaussian distribution, the maximum and minimum error values ​​can be used as the semi-major axis and semi-minor axis respectively, and an ellipse centered on the average positioning point can be drawn. The ellipse is the equal probability density distribution curve of the positioning point. At this time, the semi-major axis direction represents the maximum error direction, and the semi-minor axis direction represents the minimum error direction. Assume that the circular position line obtained by the two ground stations is P 1 , P 2 , the corresponding position line errors are ΔP 1 , ΔP 2 , since the two errors can be considered unrelated, the joint probability distribution of the position line error is:

[0108]

[0109] Among them, σ 1 , σ 2 is the standard deviation of the corresponding position line distribution, then the probability that the intersection of the position lines is located in the parallelogram formed by the tangents of the position lines is:

[0110]

[0111] Let dS = dΔP 1 dΔP 2 , then formula (18) can be rewritten as:

[0112]

[0113] Assume that the probability that the intersection of the position lines falls within the quadrilateral takes a fixed value K k When , the error distribution of classical geometric navigation positioning can be simplified to the form of standard elliptic equation:

[0114]

[0115] Among them, the semi-major axis and semi-minor axis are distributed as follows:

[0116]

[0117]

[0118] Where A is the acute angle of the position line, and the angle between its angle bisector and the semi-major axis of the ellipse It can be used to describe the direction of the semi-major axis of the ellipse. The angle can be expressed as:

[0119]

[0120] When the ranging accuracy of the two ground stations is the same and constant, the classical geometric ranging positioning error field can be represented by the error ellipse distribution at the feature point, that is, the positioning error field. Such a positioning error field can better reflect the probability distribution of the positioning error at the feature position in the working area. The maximum and minimum values ​​of the error can be calculated, and the corresponding direction can be clearly seen. The distribution of the classical geometric ranging positioning error field can be found in Figure 7 .

[0121] In the quantum ranging scheme, the ranging error increases with the increase of distance and tends to reach a maximum value. This is different from the classical circular position line error. Since the circular position line error of the quantum ranging scheme is much smaller than the classical ranging method, this conclusion means that the quantum ranging positioning scheme based on the circular position line error characteristics has a smaller positioning error than the classical geometric ranging method.

[0122] In the analysis of error characteristics, we can refer to the approach in classical geometric positioning and also consider the circular position line error to be a random variable that obeys a zero-mean Gaussian distribution, that is, the measured circular position line is considered to have the same distribution in the radial direction before and after the actual position line. At the same time, since the quantum ranging process of the two ground stations is carried out independently, the two circular position lines are unrelated. At this time, the quantum ranging positioning error is also a joint Gaussian distribution that satisfies equation (17). When the ranging accuracy of the two ground stations is the same, it has an error field similar to that of classical geometric ranging positioning, but the positioning error should be much smaller than that of the classical scheme. For the convenience of comparison, the error field distribution diagrams of the quantum ranging positioning scheme and the classical geometric ranging positioning scheme can be plotted simultaneously on Figure 7 .

[0123] The red error ellipse represents the positioning error distribution of the quantum ranging positioning solution, and the black error ellipse represents the positioning error distribution of the classical geometric ranging positioning solution. Figure 7 It can be seen that the positioning error field of the quantum ranging positioning method is consistent with the classical geometric ranging positioning method in terms of error ellipse shape, extreme value direction, working area, etc., but its error is smaller than that of the classical method and its accuracy is higher. Figure 7 The error statistics of the quantum ranging positioning scheme are given. If the specific size of the error value is needed, it can be described by the area of ​​the quadrilateral enclosed by the tangent of the position line. Its area can be approximated by a parallelogram, as shown in equation (24), which can be rewritten as

[0124] E=|Δd i |×|Δd j | (24)

[0125] 1.3 Dynamic trajectory tracking

[0126] The proposed quantum positioning method can also realize dynamic trajectory tracking of the target by continuously measuring the real-time distance of the target through two ground stations. In order to analyze the positioning performance more simply and intuitively, a rectangular coordinate system can be set with the baselines of the two stations as the horizontal coordinate and the vertical line as the vertical coordinate. Next, the dynamic trajectory tracking performance of the method is analyzed by setting two specific scenarios.

[0127] When the target moves away from G along the extended runway centerline 1 -G 2 When the direction of the baseline moves, its actual running track should be a section on the extension line of the runway centerline. This situation should be specifically converted into η in the present invention. 1 =η 2 = 0.5, and as the distance from the target increases, the transmission coefficient will continue to decrease. Based on this relationship, the actual trajectory of the target and the target trajectory measured by the scheme can be obtained, as shown in Figure 8 The red solid line and black dashed line are shown in .

[0128] Depend on Figure 8 It can be seen that the target trajectory obtained by the quantum positioning scheme is almost completely consistent with its actual running trajectory, which means that the positioning error of the present invention is very small and can be used to track the dynamic trajectory of the target.

[0129] When the target flies away from one of the ground stations at a fixed distance, its actual trajectory should be an arc on a circle with the ground station as the center and the fixed distance as the radius. This scenario should be converted into the following parameter relationship in the solution: For the convenience of explanation, assume that the ground station that the target flies around is G 2 , a fixed distance flight means η 2 remains unchanged, while η 1 Keep decreasing, let η 2 = 0.6, then the actual trajectory of the target and the target trajectory measured by the scheme can be obtained, respectively as Fig. 9 As shown by the red solid line and black dashed line in Fig. 9 It can be concluded that the target moving trajectory measured by the present invention is almost the same as its actual trajectory, and has good real-time trajectory tracking performance.

[0130] In summary, the present invention uses cavity electro-optical force converters working in two different modes as the transmitting end and the receiving end respectively, and combines more than two transmitting ends and receiving ends, proposes a quantum ranging positioning method, explains its implementation principle, and sets experimentally obtainable parameters for performance analysis, and obtains a quantum ranging positioning accuracy of 6.4×10 -7 m 2 .

Claims

1. A quantum ranging positioning device based on microwave and light entanglement, characterized in that: include: There are two ground base stations, each of which is composed of two cavity electro-optical converters, one of which is the transmitting end and the other is the receiving end. The transmitting end in each ground base station is used to prepare hybrid microwave-light wave entanglement, while the receiving end is used to receive the returned microwave signal and perform frequency band shifting and quantum state transfer on it.

2. According to claim 1, a quantum ranging positioning device based on microwave and light entanglement is characterized in that: The cavity frequency detuning amount at the transmitting end is set to Δ M =-Δ O =ω m , the cavity frequency detuning amount of the receiving end is set to Δ M =Δ O =ω m .

3. A quantum ranging positioning device method based on microwave and light entanglement, characterized in that: The following steps are involved: S1 marks one of the two ground base stations as G1 and the other as G2. The transmitter and receiver in G1 are marked as A and B respectively, and the transmitter and receiver in G2 are marked as A' and B'. A and A' prepare microwave-light wave entanglement for their respective ground stations and output microwaves Transmitted into free space, the light wave is output It is stored locally and waits for the coincidence detection with the optical wave signal output by the receiving end; S2 Each microwave signal establishes a separate beam splitter model. The corresponding transmission coefficients in the beam splitter model are η1 and η2 respectively. When the microwave signal encounters the target, part of the microwave signal is absorbed by the target surface, and part is reflected and received by the receiving antenna of the ground station. The return microwave signals of the two ground stations are recorded as After the returned microwave signal is received, the receiving end conjugates it and up-converts it into a light wave signal for output; S3 After being output, they are stored in the local Perform a correlation test to obtain The corresponding second-order coherence function, after obtaining the maximum value of the second-order coherence function, can be used to obtain the one-way transmission delay; S4 According to the one-way transmission delay and the propagation speed of microwave signals in free space, the distance between the two ground stations and the target can be calculated. Next, two circles are obtained with the two ground stations as the center and the measured distance as the radius, and the intersection of the two circles is obtained. If the two circles have only one intersection, then the intersection is the target position; if there are two intersections, one of them is the image of the target position relative to the baseline. The image point can be removed according to the direction of the ground station's transmission and reception signals or other judgment criteria to determine the target position.

4. A method for quantum ranging positioning device based on microwave and light entanglement according to claim 3, characterized in that: In S4, the distance between the two ground stations and the target is calculated as the rough distance according to the one-way transmission delay and the propagation speed of the microwave signal in free space. Since the microwave transmission delay has a certain measurement error, it is represented by the half-height full width value of the second-order coherence function here, and the timing accuracy Δτ and the distance accuracy are obtained as shown in the following formula: Δd=cΔτ (02) In formulas (01) and (02), They represent the two time points corresponding to the half-height values, so the precise distance between the ground station and the target is expressed by the following formula: D=d+cΔτ (03) In formula (03), d is the distance between the two ground stations and the target, which is the rough distance.

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