CN116184465A

CN116184465A - Satellite-based quantum positioning navigation system and method based on single satellite and ground station

Info

Publication number: CN116184465A
Application number: CN202310475698.1A
Authority: CN
Inventors: 丛爽; 汪泳钦; 尚伟伟
Original assignee: University of Science and Technology of China USTC
Current assignee: University of Science and Technology of China USTC
Priority date: 2023-04-28
Filing date: 2023-04-28
Publication date: 2023-05-30
Anticipated expiration: 2043-04-28
Also published as: CN116184465B

Abstract

The invention discloses a satellite-based quantum positioning navigation system and method based on a single satellite and a ground station, and belongs to the field of satellite navigation. According to the method, a single satellite is used for aiming, capturing and tracking a positioning navigation target, entangled light is emitted for ranging, the arrival time difference of the entangled light between the satellite and the positioning navigation target and between the satellite and a ground station, the azimuth angle and the pitch angle of the positioning navigation target relative to the satellite are obtained, the position coordinate of the positioning navigation target under a satellite pitching coordinate system is solved, and then coordinate conversion is carried out to convert the satellite pitching coordinate system into a geocentric inertial system so as to obtain the position coordinate of the positioning navigation target. According to the method, a single quantum satellite is adopted, so that a quantum positioning and navigation scheme with the number of satellites smaller than that of three satellites is realized, the number of required quantum satellites and the hardware cost of a quantum positioning system are reduced, the ground station is utilized to reduce the atmospheric delay distance error of a ranging link, and the accuracy of the positioning and navigation scheme is further improved.

Description

Satellite-based quantum positioning navigation system and method based on single satellite and ground station

Technical Field

The invention relates to the field of satellite positioning navigation, in particular to a satellite-based quantum positioning navigation system and method based on a single satellite and a ground station.

Background

The global positioning system (Global Positioning System, GPS) is proposed from the sixty generation of the last century, and adopts at least 4 satellites with known positions to send own ephemeris signals and the arrival time difference between the signals received by a user receiver to calculate the distance between each satellite and a user, and simultaneously four equations are used for calculating the space three-dimensional coordinates of the user so as to realize the positioning of the user. With the needs of people in production and the progress of technology and the continuous development of the fields of aerospace, military, artificial intelligence and the like, people continuously put forward higher performance requirements in the aspects of positioning and navigation range and ranging precision, so that laser and quantum positioning systems with higher precision are proposed and researched worldwide.

The Quantum Positioning System (QPS) is a concept which is put forward for the first time in 2001, quantum is introduced into the positioning system by means of preparation of quantum entanglement state and transmission technology thereof, electromagnetic wave pulse is not used any more, and the entanglement characteristic of quantum makes QPS have great superiority in two aspects of positioning precision and information confidentiality. The advantages of QPS in positioning accuracy are presented in: the signal source adopted by the QPS is a quantum entanglement state with good coherence, stable phase and high frequency purity, the bandwidth, spectrum and power of the pulse and the number of photons in the pulse determine the measurement accuracy of the arrival time, and the greater the number of photons, the greater the measurement accuracy of the arrival time of laser can be improved to a great extent. Research and analysis prove that compared with the traditional satellite positioning navigation system, the QPS is improved to 10 in measurement precision ^-13 This is the fundamental reason for the QPS to obtain a high accuracy positioning.

The advantages of QPS in information security are represented by: even if other people can intercept part of photons emitted by the positioning point and in an entangled state, the interceptor cannot acquire the position coordinates of the positioning point. On the other hand, QPS technology also provides a possibility of detecting eavesdropping by others, because once eavesdropping occurs in the quantum transmission channel between the pending point and the reference point, the system can generate obvious interference due to the existence of eavesdropping, and meanwhile, analysis of noise interference characteristics can be similar, so that the existence of eavesdropping can be shown in the form of peak spectrum. At this point, the system may continue to operate properly by changing the communication frequency or channel.

The quantum positioning system for early domestic and foreign researches is basically a baseline-based interference type quantum positioning system proposed by Bahde in 2004, and is a system formed by six satellites, each two satellites form a baseline pair, an entangled photon source is placed on one satellite on each baseline pair, the entangled photon pair emitted by the entangled photon source obtains two entangled lights entangled with each other through a polarization beam splitter, one entangled light is directly emitted to a user along a quantum communication link, and a single photon reflected by the user along the original path is detected by a single photon detector on the satellite; the other beam of entangled light is emitted to the other satellite on the base line pair along the other quantum communication link, reflected to the user through the satellite, the satellite with entangled photon source is placed at the position of the user along the original path reflection back, detected by the other single photon detector, the arrival time difference of the entangled light on the two quantum communication links is obtained according to coincidence measurement, and the positioning of the user is realized by utilizing the principle based on the arrival time difference (Time Difference of Arrival, TDOA).

In 2019, cong Shuang et al proposed a three satellite-based quantum positioning and navigation system. The ATP systems of the three satellites respectively transmit beacon light with the ATP systems of the ground user side to establish a quantum communication link; then, one path of photons generated by the entangled photon pair generator is emitted out through a satellite end ATP system, reaches a ground end ATP system along a quantum communication link, returns to enter a 50:50 spectroscope from a ground pyramid reflector in a return way, and the other path of signals directly enter the 50:50 spectroscope after passing through an adjustable optical delay; the two paths of optical signals respectively pass through two single photon detectors and then are sent into a coincidence counter to carry out coincidence counting, so as to obtain an arrival time difference; and respectively establishing distance equations between three satellites and the ground according to the relation that the product of the position coordinates of the quantum satellites and the obtained arrival time difference and the light speed is equal to twice the distance between the satellite end and the ground user end, and solving the accurate position coordinates of the user. How to further reduce the number of satellites required and the hardware cost of the quantum positioning system, and how to use as few quantum satellites as possible to achieve the required positioning and navigation accuracy is a problem that needs to be further solved.

In view of this, the present invention has been made.

Disclosure of Invention

The invention aims to provide a satellite-based quantum positioning navigation system and a satellite-based quantum positioning navigation method based on a single satellite and a ground station, which can realize high-precision positioning and navigation of a positioning navigation target by matching the single satellite with the ground station, reduce the positioning navigation cost and further solve the technical problems in the prior art.

The invention aims at realizing the following technical scheme:

a satellite-based quantum positioning navigation system based on a single satellite and a ground station, comprising:

satellite terminal processing equipment, ground station processing equipment and positioning navigation equipment; wherein,

the satellite terminal processing equipment is arranged on a single satellite, and can respectively send beacon light with the positioning navigation equipment and the ground station processing equipment to establish a first quantum communication link and a second quantum communication link, and the azimuth angle and the pitch angle of the positioning navigation equipment relative to the single satellite are calculated according to the information of the first quantum communication link; the two-photon pair with entanglement compression characteristics can be generated and split to generate a first path of quantum light signal and a second path of quantum light signal, the two paths of quantum light signals are respectively communicated with the positioning navigation device and the ground station processing device through two quantum communication links to obtain two paths of digital pulse signals, the arrival time difference between a single satellite and the ground station processing device and between the single satellite and the positioning navigation device is obtained according to the two paths of digital pulse signals, the actual distance between the single satellite and the positioning navigation device is calculated through the arrival time difference and the actual distance between the single satellite and the ground station processing device, the position of the positioning navigation device under a satellite pitching coordinate system is calculated according to the azimuth angle and pitch angle of the positioning navigation device relative to the single satellite and the actual distance between the single satellite and the positioning navigation device, the position is converted into a geocentric inertial system to obtain the positioning position of the positioning navigation device, and the ground position is sent to the positioning navigation device for positioning; the advanced aiming angle can be calculated through the current speed of the single satellite and the current speed of the positioning navigation equipment, the advanced aiming angle is used as tracking compensation to be sent to the positioning navigation equipment, the optical signals reflected by the advanced aiming angle are received by the positioning navigation equipment, coincidence counting is carried out in combination with the reference optical path signals established by the ground station processing equipment, so that the mobile positioning navigation equipment is subjected to capturing tracking and real-time positioning, and the navigation of the mobile positioning navigation equipment is completed;

The ground station processing equipment performs quantum optical communication with the satellite terminal processing equipment, can mutually send beacon light with the satellite terminal processing equipment, and establishes a second quantum communication link so that the satellite terminal processing equipment obtains a reference light path signal;

the positioning navigation equipment is in quantum optical communication with the satellite terminal processing equipment, can mutually send beacon light with the satellite terminal processing equipment, and establishes a first quantum communication link so that the satellite terminal processing equipment calculates an azimuth angle and a pitch angle of the positioning navigation equipment relative to a single satellite according to the information of the first quantum communication link; and in a static state, receiving a first path of quantum light signal sent by the satellite terminal processing equipment and reflecting the first path of quantum light signal back to the satellite terminal processing equipment for processing so as to determine the positioning position of the positioning navigation equipment, and receiving the positioning position of the positioning navigation equipment sent by the satellite terminal processing equipment to realize positioning; and in a moving state, receiving a first path of optical signal sent by the satellite processing equipment, reflecting the first path of optical signal to the satellite processing equipment of the moving single satellite according to an advanced aiming angle deviated from a beacon optical axis, processing the first path of optical signal by the satellite processing equipment, and carrying out capturing tracking and real-time positioning on the moving positioning navigation equipment by combining with a reference optical path signal to finish the navigation of the moving positioning navigation equipment.

The invention discloses a satellite-based quantum positioning navigation method based on a single satellite and a ground station, which comprises the following steps:

the satellite terminal processing equipment of the system respectively sends beacon light with the positioning navigation equipment and the ground station processing equipment to establish a first quantum communication link and a second quantum communication link, and the azimuth angle and the pitch angle of the positioning navigation equipment relative to a single satellite are calculated according to the information of the first quantum communication link;

when positioning the positioning navigation equipment of the system, the satellite end processing equipment generates a two-photon pair with entanglement compression characteristic, and splits into a first path of quantum optical signals and a second path of quantum optical signals, the two paths of quantum optical signals are respectively communicated with the positioning navigation equipment and the ground station processing equipment through two quantum communication links to obtain two paths of digital pulse signals, the arrival time difference between the single satellite and the ground station processing equipment and between the single satellite and the positioning navigation equipment is obtained according to the two paths of digital pulse signals, the actual distance between the single satellite and the positioning navigation equipment is obtained through the arrival time difference and the actual distance between the single satellite and the ground station processing equipment, the position of the positioning navigation equipment under a pitching coordinate system on the satellite is calculated according to the azimuth angle, the pitching angle and the actual distance between the single satellite and the positioning navigation equipment of the positioning navigation equipment, the position is converted into a ground inertial system to obtain the positioning position of the positioning navigation equipment, and the ground position is sent to the positioning navigation equipment for positioning;

When the mobile positioning navigation equipment is navigated, the satellite end processing equipment calculates an advanced aiming angle through the current speed of a single satellite and the current speed of the positioning navigation equipment, sends the advanced aiming angle to the positioning navigation equipment as tracking compensation, receives optical signals reflected by the positioning navigation equipment based on the advanced aiming angle, and performs coincidence counting together with reference optical path signals established by the ground station processing equipment so as to capture, track and position the mobile positioning navigation equipment in real time, thereby completing the navigation of the mobile positioning navigation equipment.

Compared with the prior art, the satellite-based quantum positioning navigation system and method based on the single satellite and the ground station provided by the invention have the beneficial effects that:

the satellite terminal processing equipment is arranged on a single satellite and is respectively in quantum communication with the ground station processing equipment and the positioning navigation equipment, so that a quantum positioning and navigation scheme adopting a least number of satellites, namely one quantum satellite and one ground station, is realized, the cost of positioning and navigation of the whole satellite is reduced, and the accuracy of the positioning and navigation scheme can be ensured. Meanwhile, the ground station processing equipment is added, so that the influence of the atmospheric delay distance error between the satellite and the positioning navigation target in the ranging link can be reduced, and the ranging accuracy is further improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic diagram of spatial distribution of a quantum positioning and navigation system based on a single satellite and a ground station according to an embodiment of the present invention.

Fig. 2 is a functional block diagram of positioning between a satellite and a positioning navigation device and a ground station processing device in a quantum positioning system based on a single satellite and a ground station according to an embodiment of the present invention.

Fig. 3 is a schematic flow chart of a satellite-based quantum positioning system based on a single satellite and a ground station according to an embodiment of the present invention.

Fig. 4 is a schematic diagram of a process of coincidence counting of two photons generated by a generator by entangled photons in a system according to an embodiment of the present invention.

Fig. 5 is a time spectrum diagram of a typical coincidence counting curve and curve fitting thereof obtained after two paths of entangled photons pass through a coincidence counter in the system provided by the embodiment of the present invention.

Detailed Description

The technical scheme in the embodiment of the invention is clearly and completely described below in combination with the specific content of the invention; it will be apparent that the described embodiments are only some embodiments of the invention, but not all embodiments, which do not constitute limitations of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to fall within the scope of the invention.

The terms that may be used herein will first be described as follows:

the term "and/or" is intended to mean that either or both may be implemented, e.g., X and/or Y are intended to include both the cases of "X" or "Y" and the cases of "X and Y".

The terms "comprises," "comprising," "includes," "including," "has," "having" or other similar referents are to be construed to cover a non-exclusive inclusion. For example: including a particular feature (e.g., a starting material, component, ingredient, carrier, formulation, material, dimension, part, means, mechanism, apparatus, step, procedure, method, reaction condition, processing condition, parameter, algorithm, signal, data, product or article of manufacture, etc.), should be construed as including not only a particular feature but also other features known in the art that are not explicitly recited.

The term "consisting of … …" is meant to exclude any technical feature element not explicitly listed. If such term is used in a claim, the term will cause the claim to be closed, such that it does not include technical features other than those specifically listed, except for conventional impurities associated therewith. If the term is intended to appear in only a clause of a claim, it is intended to limit only the elements explicitly recited in that clause, and the elements recited in other clauses are not excluded from the overall claim.

Unless specifically stated or limited otherwise, the terms "mounted," "connected," "secured," and the like should be construed broadly to include, for example: the connecting device can be fixedly connected, detachably connected or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms herein above will be understood by those of ordinary skill in the art as the case may be.

The terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," etc. refer to an orientation or positional relationship based on that shown in the drawings, merely for ease of description and to simplify the description, and do not explicitly or implicitly indicate that the apparatus or element in question must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present disclosure.

The satellite-based quantum positioning navigation system and the satellite-based quantum positioning navigation method based on the single satellite and the ground station provided by the invention are described in detail below. What is not described in detail in the embodiments of the present invention belongs to the prior art known to those skilled in the art. The specific conditions are not noted in the examples of the present invention and are carried out according to the conditions conventional in the art or suggested by the manufacturer. The reagents or apparatus used in the examples of the present invention were conventional products commercially available without the manufacturer's knowledge.

As shown in fig. 1 and 2, an embodiment of the present invention provides a satellite-based quantum positioning navigation system based on a single satellite and a ground station, including:

In the above system, the satellite terminal processing device includes:

the system comprises an entangled photon pair generator, a beam splitter, a first satellite ATP system, a second satellite ATP system, a coincidence counter, a first single photon detector, a second single photon detector and a signal processing module; wherein,

the output end of the entangled photon pair generator is connected with the beam splitter, the two output ends of the beam splitter are respectively connected with the first satellite ATP system and the second satellite ATP system, the entangled photon pair generator can emit entangled photon pairs which are divided into two paths of photon signals by the beam splitter, wherein the first path of photon signals enter the first satellite ATP system, and the second path of photon signals enter the second satellite ATP system;

the optical signal port of the first satellite ATP system is in optical communication connection with the positioning navigation equipment, can establish a first quantum communication link with the positioning navigation equipment, and transmits a first path of quantum optical signals to the positioning navigation equipment;

the optical signal port of the second satellite ATP system is in optical communication connection with the ground station processing equipment, can establish a second quantum communication link with the ground station processing equipment, and transmits a second quantum optical signal to the ground station processing equipment;

The first single photon detector is respectively connected with the positioning navigation equipment and the coincidence counter in an optical communication way, can receive optical signals reflected by the positioning navigation equipment and sends the optical signals to the coincidence counter;

the second single photon detector is respectively connected with the ground station processing equipment and the coincidence counter in an optical communication manner, can receive optical signals reflected by the ground station processing equipment and sends the optical signals to the coincidence counter;

the signal processing module is respectively connected with the signal output end of the first satellite ATP system, the output end of the coincidence counter and the positioning navigation equipment in a communication way, can receive the information of a first quantum communication link output by the first satellite ATP system, and calculates the azimuth angle and the pitch angle of the positioning navigation equipment relative to a single satellite; the method comprises the steps of obtaining a pulse number according to a coincidence count of a coincidence counter, fitting a curve formed by the pulse number to obtain a fitting curve, determining arrival time differences between a single satellite and a ground station and between the single satellite and positioning navigation equipment through an abscissa of a peak value on the fitting curve, calculating the actual distance between the single satellite and the positioning navigation equipment through the arrival time differences and the actual distance between the single satellite and the ground station, calculating the position of the positioning navigation equipment under a satellite pitching coordinate system according to the azimuth angle and pitch angle of the positioning navigation equipment relative to the single satellite and the actual distance between the single satellite and the positioning navigation equipment, converting the position to a geocentric inertial system to obtain the positioning position of the positioning navigation equipment, and transmitting the ground position to the positioning navigation equipment; and the advanced aiming angle can be calculated through the current speed of the single satellite and the current speed of the positioning navigation equipment, the advanced aiming angle is used as tracking compensation to be sent to the positioning navigation equipment, the light signals reflected by the advanced aiming angle are received by the positioning navigation equipment, coincidence counting is carried out in combination with the reference light path signals established by the ground station processing equipment, so that the mobile positioning navigation equipment is subjected to capturing tracking and real-time positioning, and the navigation of the mobile positioning navigation equipment is completed.

In the above system, the first satellite ATP system and the second satellite ATP system have the same configuration, and each of them includes:

the system comprises a beacon light module, a coarse tracking module and a fine tracking module; wherein:

the beacon light module consists of a beacon light source and can emit beacon light for establishing an inter-satellite-to-ground communication link to the general direction of the opposite end between the satellite end processing equipment and the positioning navigation equipment and between the satellite end processing equipment and the ground station processing equipment respectively;

the coarse tracking module is connected with the output end of the beam splitter, can initially position the incident optical axis of the beacon light, and can capture and coarse track the beacon light;

the fine tracking module is connected with the output end of the coarse tracking module, and can calculate an advanced aiming angle so that the incident optical axis of the beacon light is aligned with the optical axis of the coarse tracking module.

In the above system, the coarse tracking module includes: the device comprises an optical antenna, a two-dimensional turntable, a coarse tracking detector and a coarse tracking controller; wherein,

the optical antenna is arranged on the two-dimensional turntable and is positioned at the output end of the beam splitter and used for transmitting and receiving beacon light and quantum light signals between the satellite end processing equipment and the ground station processing equipment, the capturing of the beacon light and the quantum light signals between the satellite terminal processing equipment and the ground station processing equipment is completed by preliminarily judging the position of the other party according to the satellite orbit forecast or the range of the ground station processing equipment and rotating the optical antenna through the two-dimensional turntable;

The coarse tracking detector is in communication connection with the coarse tracking controller, the light spot signal of the beacon light can be detected and sent to the coarse tracking controller;

the coarse tracking controller is electrically connected with the two-dimensional turntable, and can calculate a control quantity according to the light spot signal sent by the coarse tracking detector by using a control algorithm, and control the rotation of the two-dimensional turntable according to the control quantity to adjust the direction of the optical antenna so as to introduce the light spot signal of the beacon light into the view field of the fine tracking module;

the fine tracking module comprises: the system comprises a fine tracking detector, a fine tracking controller, a quick reflector and a quick reflector sensor; wherein,

the fine tracking detector is in communication connection with the fine tracking controller, and can receive the beacon light spot signal output by the coarse tracking module, convert the beacon light spot signal into an angle deviation signal, calculate an advanced aiming angle according to the angle deviation signal and output the advanced aiming angle to the fine tracking controller;

the fine tracking controller is electrically connected with the quick reflector, can calculate corresponding control signals according to an advanced aiming angle and a set control algorithm, drives the quick reflector to deflect by a corresponding angle, and compensates the angle error of the coarse tracking module tracking beacon light;

The fast reflector sensor is arranged at the fast reflector, is electrically connected with the fine tracking controller, can measure the deflection angle of the fast reflector, and transmits the deflection angle into the signal processing module for calculating the position of the positioning navigation equipment.

In the above system, the signal processing module calculates the azimuth angle E of the positioning navigation device relative to the single satellite according to the following formula according to the information of the first quantum communication link output by the first satellite ATP system ₁ And pitch angle A ₁ The formula is:

；/>

wherein ,

、/>

respectively representing deflection angles on a pitching axis and an azimuth axis of a two-dimensional turntable of a coarse tracking module of the first satellite ATP system; />

、/>

Respectively obtaining deflection angle values to be compensated for a pitching axis and an azimuth axis of the two-dimensional turntable; />

、/>

The deflection angles on a pitching axis and an azimuth axis of a fast reflecting mirror of a fine tracking module of the first satellite ATP system are respectively; />

、/>

And respectively compensating deflection angle values of a pitching axis and an azimuth axis of the quick reflector.

In the above system, the coincidence counter includes: a nanosecond delayer, a time-amplitude converter and a multichannel analyzer which are connected in sequence; wherein,

the nanosecond delayer can adjust the time delay value between the digital pulse signals output by the first single photon detector and the second single photon detector, and send the two paths of adjusted digital pulse signals into the time-amplitude converter as a start signal and an end signal;

The time-amplitude converter can output a level signal with corresponding amplitude to the multichannel analyzer according to the time difference value of the input starting signal and the input ending signal;

the multichannel analyzer can perform coincidence counting measurement on the level signals output by the time-amplitude converter, and output a time spectrogram corresponding to coincidence counting results under different time delays.

In the above system, the positioning navigation device includes:

positioning and navigating target ATP system a first cone reflector and a signal receiving module; wherein,

the positioning navigation target ATP system is respectively connected with the satellite end processing equipment and the first pyramid reflector in an optical communication way, can establish a first quantum communication link with the satellite ATP system of the satellite end processing equipment, receives a first path of quantum optical signals emitted by the first satellite ATP system of the satellite end processing equipment and sends the first path of quantum optical signals to the first pyramid reflector;

the first angular cone reflector is in optical communication connection with a first single photon detector of the satellite terminal processing equipment and can reflect the received first path of quantum optical signals to the first single photon detector;

the signal receiving module is in communication connection with the signal processing module of the satellite terminal processing equipment and is used for receiving the arrival time difference and the quantum satellite coordinates.

The constitution of the positioning navigation target ATP system is the same as that of the first satellite ATP system, and the above description of the constitution of the first satellite ATP system is referred to and will not be repeated here.

In the above system, the ground station processing device includes:

a ground station ATP system and a second pyramid reflector; wherein,

the ground station ATP system is respectively connected with the satellite end processing equipment and the second pyramid reflector in an optical communication way, can establish a second quantum communication link with the satellite ATP system of the satellite end processing equipment, and receives a second path of quantum optical signals emitted by the second satellite ATP system of the satellite end processing equipment and sends the second quantum optical signals to the second pyramid reflector;

the second pyramid reflector is in optical communication connection with a second single photon detector of the satellite terminal processing equipment and can reflect the received second path of quantum optical signals to the second single photon detector.

The construction of the above-described ground station ATP system is the same as that of the second satellite ATP system, and reference is made to the above description of the construction of the second satellite ATP system, which is not repeated here.

Referring to fig. 3, the embodiment of the invention further provides a satellite-based quantum positioning navigation method based on a single satellite and a ground station, which adopts the system and comprises the following steps:

In the method, the satellite terminal processing equipment calculates the actual distance between the single satellite and the positioning navigation equipment through the arrival time difference and the actual distance between the single satellite and the ground station processing equipment in the following way

The method comprises the following steps:

；

wherein C is the speed of light;

time differences of arrival between the single satellite to the ground station processing device and between the single satellite to the positioning navigation device; r is R _sgs For passing the position coordinates S (x _s0 ，y _s0 ，z _s0 ) And the position coordinates G (x _g0 ，y _g0 ，z _g0 ) The actual distance R between the single satellite and the ground station processing equipment _sgs Calculated according to the following formula:

；

the satellite end processing equipment is used for processing the azimuth angle E of the navigation equipment relative to the satellite according to the positioning ₁ Pitch angle A ₁ And an actual distance R _sgt And positioning the position (r) of the navigation device in the satellite pitch coordinate system _sg-x ,r _sg-y ,r _sg-z ) The following relationship:

；

solving the position (r) of the positioning navigation device on the satellite under the pitching coordinate system _sg-x ,r _sg-y ,r _sg-z )。

On-satellite based positioning navigation device position (r) under upper pitch coordinate system _sg-x ,r _sg-y ,r _sg-z ) And knowing the satellite current position coordinates S (x _s0 ，y _s0 ，z _s0 ) The listed positioning locations (x _g ,y _g ,z _g ) Is defined by the equation: (x) _s0 -x _g ,y _s0 -y _g ,z _s0 -z _g )=D ^-1 ×(r _sg-x ,r _sg-y ,r _sg-z ) The following solution equation is derived to locate the position (r) of the navigation device in the pitch coordinate system on the satellite _sg-x ,r _sg-y ,r _sg-z ) Conversion to a geocentric inertial system yields a position location (x) of the positioning navigation device _g ,y _g ,z _g ) The solution equation is:

；

wherein ,S(x_s0 ，y _s0 ，z _s0 ) The current position coordinates of satellites known under the geocentric inertial system; e (E) ₁ 、 A ₁ 、R _sgt Respectively positioning azimuth angle, pitch angle and actual distance of the navigation equipment relative to the satellite; d is a coordinate transformation matrix from the geocentric inertial system to the satellite pitch coordinate system, where the coordinate transformation matrix D is expressed as:

；

；

in the coordinate transformation matrix D, the six parameters of the satellite orbit are used: inclination angle i of the track, ascending intersection point right through omega and near-place radial angle omega; set the geocenter inertia Ox _i y _i z _i The unit vector of the three directions in the system is x _l 、y _l 、z ₁ ； wherein ,y_l And x _l 、z ₁ Forms a right hand system and is provided with a satellite upper pitching coordinate system Ox _s y _s z _s Unit vector x of three directions in (3) _s 、y _s 、z _s； wherein ,z_s And x _s 、y _s Forming a right hand system; the geocentric inertial system is converted into a satellite on-board pitching coordinate system, and the coordinate system is regarded as being firstly around z ₁ Direction is rotated by omega angle, and then is wound around x _l Direction rotates by an angle of i, and finally winds the current z ₁ And (3) rotating the direction by omega angle to obtain the satellite upper pitching coordinate system.

In the method, the atmospheric delay distance error in the quantum communication link can be reduced by the ground station processing equipment, and the method concretely comprises the following steps:

measuring distance between satellite of quantum positioning system based on single satellite and positioning navigation equipment

Actual distance from satellite to positioning navigation device +.>

The relation between them is:

；

wherein ,

is the atmospheric delay distance error between the satellite and the positioning navigation device.

After adding a ground station processing device, the relation between the measured distance and the actual distance of each of the two quantum communication links is as follows:

；

wherein ,

processing the actual distance between the device for the satellite to the ground station; />

For the measured distance between the satellite and the ground station processing equipment; />

The atmospheric delay distance error between the devices is handled for satellite to ground stations.

The above two formulas are subtracted to obtain:

；

from time differences of arrival measured by coincidence counters

The measured distance between the satellite and the positioning navigation device can be obtained/>

And a measured distance between the satellite and the ground station processing device +.>

The relation of (2) is:

；

the actual distance between the satellite and the positioning and navigation device

The final expression of (2) is:

；

from the above formula, it can be seen that: because the locations of the satellite and the ground station processing equipment are known, the actual distance between the satellite and the ground station processing equipment

Can be accurately calculated. Actual distance between satellite and positioning navigation device in quantum positioning system based on single satellite only>

In comparison, because of->

Therefore->

According to the invention, by adding ground station processing equipment, after a satellite-based quantum positioning and navigation system based on a single satellite and a ground station is adopted, the atmospheric delay distance error is from +.>

Reduce to

。

In summary, the system and the method of the embodiment of the invention realize accurate positioning and navigation of the positioning navigation equipment based on the single satellite carrying the satellite terminal processing equipment and the ground station processing equipment, effectively reduce the number of satellites and the overall cost of the satellite-based quantum positioning navigation system on the premise of ensuring the positioning and navigation accuracy.

In order to clearly show the technical scheme and the technical effects provided by the invention, the satellite-based quantum positioning navigation system and the satellite-based quantum positioning navigation method based on the single satellite and the ground station provided by the embodiment of the invention are described in detail in the following.

Example 1

The embodiment of the invention provides a satellite-based quantum positioning navigation system based on a single satellite and a ground station, which aims to position and navigate a measured object with high precision by using as few quantum satellites as possible and reduce an atmospheric delay distance error in a ranging link by using ground station processing equipment. The system comprises: satellite terminal processing equipment, positioning navigation equipment and ground station processing equipment; wherein,

the satellite processing device is shown in fig. 2, and includes: the system comprises an entangled photon pair generator, a beam splitter, a first satellite ATP system, a second satellite ATP system, a first single photon detector, a second single photon detector, a coincidence counter and a signal processing module.

The positioning navigation device includes: a navigation target ATP system, a first cone reflector, and a signal receiving module are positioned. The positioning navigation device is arranged on a positioning navigation target, and if no special description exists, the positioning navigation target refers to a target to be positioned and navigated of the positioning navigation device in the following description of the scheme.

The ground station processing apparatus includes: a ground station ATP system and a second pyramid reflector. In the following description of the scheme, unless otherwise specified, the ground stations are simply referred to as ground station processing devices, and the meaning of the two is the same.

The satellite terminal processing equipment is arranged on a single satellite, the ground station processing equipment is arranged on a ground station, the positioning navigation equipment is arranged on a positioning navigation target, a near-earth orbit spacecraft, a deep space and inter-satellite flying spacecraft, a celestial body lander and a surface cruiser, and the three form a satellite-based quantum positioning navigation system together; the positioning and navigation process is as follows:

the first satellite ATP system and the second satellite ATP system respectively send beacon light with the positioning navigation target ATP system and the ground station ATP system, capture, tracking and aiming are completed after scanning alignment, and two quantum communication links are established, namely the first quantum communication link and the second quantum communication link; simultaneously, a two-dimensional turntable of a first quantum communication link between the first satellite ATP system and the positioning navigation target ATP system is measured through a quick reflector sensor of the first satellite ATP system, and the deflection angle of the quick reflector, the outputs of the coarse tracking module and the fine tracking module are fed into a signal processing module together to obtain the azimuth angle and the pitch angle of positioning navigation equipment relative to a satellite; the entangled photon pair generator generates two-photon pairs with entangled compression characteristics, and the generated two-path photon quantum light is subjected to beam splitting treatment through the beam splitter; one path of photons is used as a first path of quantum optical signals to be transmitted to a first cone reflector of positioning navigation equipment along a first quantum communication link established by a first satellite ATP system and a positioning navigation target ATP system, and then the first path of photons returns to a first single photon detector which enters a satellite; the other path of photons is used as a second path of quantum optical signals to be emitted out through a second satellite ATP system, and reaches the ground station ATP system along a second quantum communication link, and the photons also return to the satellite end through a second pyramid reflector of the ground station processing equipment and enter a second single photon detector; obtaining two paths of digital pulse signals from the two paths of single photon detectors; sending the obtained two paths of digital pulse signals into a coincidence counter for coincidence counting, fitting a curve formed by the pulse numbers obtained by coincidence counting, wherein the abscissa of the peak value on the fitted curve corresponds to the arrival time difference between the satellite and the ground station processing equipment and between the satellite and the positioning navigation target of the bearing positioning navigation equipment, and the actual distance between the satellite and the positioning navigation target can be calculated through the arrival time difference and the actual distance between the satellite and the ground station processing equipment; the signal processing module of the satellite calculates the position of the positioning navigation target on the satellite in a pitching coordinate system according to the azimuth angle and pitch angle of the positioning navigation target relative to the satellite and the actual distance between the satellite and the positioning navigation target, then converts the position into a geocentric inertial system to obtain the position of the positioning navigation target, and finally sends the position information to the signal receiving module of the positioning navigation equipment of the positioning navigation target.

When the mobile positioning navigation equipment is navigated, in a first quantum communication link between a first satellite ATP system and a positioning navigation target ATP system, a first path of quantum light signal deviates from a beacon optical axis by an advanced aiming angle, the first satellite ATP system calculates the advanced aiming angle through the current speeds of a satellite and the positioning navigation equipment, the advanced aiming angle is input into a rough tracking module in the first satellite ATP system for compensation, an optical antenna is transmitted to a first cone reflector in the positioning navigation target ATP system of the positioning navigation equipment, and after the positioning navigation target ATP system calculates the super-front aiming angle, the first cone reflector reflects the first cone reflector to the first satellite ATP system of the mobile satellite by the advanced aiming angle deviating from the beacon optical axis; the second satellite ATP system continuously transmits beacon light with the ground station ATP system, and is used for obtaining a reference light path signal, inputting the reference light path signal and the signal light path into a coincidence counter together after respectively passing through single photon detectors of the respective light paths, capturing and tracking the moving positioning navigation equipment and positioning the moving positioning navigation equipment in real time, and completing the navigation of the moving positioning navigation equipment.

The spatial distribution of the quantum positioning navigation system based on a single satellite and a ground station provided by the embodiment of the invention is shown in figure 1. In the embodiment of the invention, the method for obtaining the azimuth angle and the pitch angle of the positioning navigation equipment relative to the satellite is as follows: the first satellite ATP system and the positioning navigation target ATP system mutually send beacon light, and after scanning alignment, capturing, tracking and aiming are completed, and a first quantum communication link is established; meanwhile, the accurate tracking mode of the first satellite ATP system The fast reflector sensor of the block measures the deflection angle of the two-dimensional turntable and the fast reflector in the first satellite ATP system, and outputs of the coarse tracking module and the fine tracking module are sent to the signal processing module together to obtain the pitch angle of the positioning navigation target relative to the satellite

And azimuth->

：

；

wherein ,

、/>

the deflection angles on the pitching axis and the azimuth axis of the two-dimensional turntable of the coarse tracking module in the first satellite ATP system are respectively +.>

、/>

Deflection angle values which are required to be compensated for a pitching axis and an azimuth axis of a two-dimensional turntable of a coarse tracking module in a first satellite ATP system are respectively +.>

、/>

The deflection angles of the fast reflecting mirror of the fine tracking module in the first satellite ATP system on the pitching axis and the azimuth axis are respectively +.>

、/>

Respectively the fine tracking modules in the first satellite ATP systemThe tilt and azimuth axes of the fast mirror require offset angle values.

The principle of obtaining two photons is as follows: the first satellite ATP system and the second satellite ATP system respectively send beacon light with the positioning navigation target ATP system and the ground station ATP system, and after scanning alignment, capturing, tracking and aiming are completed, and two quantum communication links are established; the first single photon detector and the second single photon detector respectively obtain photons from two quantum communication links, and then the photons are transmitted into the coincidence counter; the coincidence counter obtains the number of pulses which reach the preset coincidence gate width simultaneously in each sampling period; drawing a second-order curve graph according to the arrival time difference and the recorded corresponding coincidence pulse number; obtaining the arrival time difference between the satellite and the positioning navigation equipment and between the satellite and the ground station processing equipment according to the abscissa corresponding to the minimum value of the curve

；

In the positioning process, a satellite-based quantum positioning navigation system based on a single satellite and a ground station firstly passes through the position coordinates of the satellite

And the position coordinates of the ground station processing device +.>

Finding the actual distance between the satellite and the ground station processing device +.>

The method comprises the following steps:

；

time difference of arrival between satellite-positioning navigation device link and satellite-ground station processing device link obtained from coincidence counter

And the actual distance between the satellite and the ground station processing equipmentLeave->

Calculating the actual distance +.>

The method comprises the following steps:

；

wherein C is the speed of light.

Positioning the azimuth of a navigation device relative to a satellite

Pitch angle->

And actual distance->

Positioning the navigation device in the satellite pitch coordinate system>

The relationship between them is as follows:

；

solving the position of positioning navigation equipment under the pitching coordinate system on satellite

After that, the satellite current position coordinates under the geocentric inertial system are known to be +.>

It is possible to list the position of the navigation device with respect to the unknowns +.>

Is defined by the equation: />

；

The coordinate transformation matrix from the geocentric inertial system to the satellite pitch coordinate system is set as D, and the coordinate transformation matrix is used in six parameters of the satellite orbit: inclination angle of rail

The ascending intersection is right through- >

Near-site irradiance->

. Set the geocentric inertial system->

The unit vector of the three directions is +.>

，/>

，/>

；/>

And->

，/>

Forming a right-hand system. Set up the satellite on-the-satellite pitching coordinate system +.>

Unit vector of three directions +.>

，/>

，/>

；/>

And->

，/>

Forming a right-hand system. The conversion of the geocentric inertial system into the satellite-borne pitch coordinate system can be regarded as the coordinate system first winding +.>

Direction rotation->

Angle, rewind->

Direction rotation->

Angle, finally rewind the current +>

Direction rotation->

The angle can obtain the satellite pitch coordinate system, so the coordinate transformation matrix from the geocentric inertia system to the satellite pitch coordinate system can be expressed as D:

；

；

azimuth angle of positioning navigation device relative to satellite

Pitch angle->

And actual distance->

Carry in, combine the satellite current position coordinate to be +.>

Then the position of the positioning navigation equipment is obtained by converting the position into a geocentric inertial system

The solution equation is:

；

quantum positioning system based on single satellite, and measuring distance between satellite and positioning navigation equipment

And the actual distance between the satellite and the positioning and navigation device>

The relation between them is:

；

wherein ,

After adding a ground station processing device, the relation between the measured distance and the actual distance of each of the two links is as follows:

；

wherein ,

set up for satellite to ground station processingActual distance between the preparations>

For the measured distance between satellite and ground station processing equipment, < > j->

Is the atmospheric delay distance error between the satellite and the ground station. The above two formulas are subtracted to obtain:

；

from time differences of arrival measured by coincidence counters

It is possible to obtain the measured distance +.between the satellite and the positioning and navigation device>

Distance between satellite and ground station>

The relation of (2) is:

；

then

The expression of (2) is:

；

from this it can be seen that: because the locations of the satellite and the ground station processing equipment are known, the actual distance between the satellite and the ground station processing equipment

Can be accurately calculated. And->

In comparison with that because

Therefore->

. The atmospheric delay distance error is increased from +.>

Reduce to->

。

The positioning and navigation principle and the working process thereof can be used in the fields of static positioning navigation target positioning and mobile positioning navigation target navigation on the ground, and can also be used in the application fields of high-precision autonomous positioning navigation of a near-earth orbit spacecraft, a deep space and inter-planetary flying spacecraft, a celestial body lander, a surface cruiser thereof and the like.

As shown in fig. 2, the entangled photon pair generator, the beam splitter, the first satellite ATP system, the second satellite ATP system, the first single photon detector, the second single photon detector, the signal processing module, and the coincidence counter are disposed at the satellite end, the positioning navigation target ATP system, the first pyramid reflector, and the signal receiving unit are disposed at the positioning navigation target end, and the ground station ATP system, the second pyramid reflector, and the signal receiving unit are disposed at the ground station end, so as to jointly form the satellite-based quantum positioning and navigation system.

In fig. 2, the entangled photon pair generator generates a two-photon pair with entangled compression characteristic, and performs beam splitting processing through a beam splitter, wherein signal light is emitted to a first angular cone reflector of a positioning navigation target by a satellite end along a quantum communication link established by a first satellite ATP system and a positioning navigation target ATP system, and then returns to a single-photon detector into which the satellite enters in a return way; the other path of photons are used as reference light signals and are transmitted to a second pyramid reflector of the ground station by the satellite end along a quantum communication link established by a second satellite ATP system of the satellite end and an ATP system of the ground station, and the other path of photons returns to a second single photon detector which enters the satellite; obtaining two paths of digital pulse signals from the two paths of single photon detectors; and outputting a digital pulse signal, sending the digital pulse signal to a coincidence counter for coincidence counting to obtain the arrival time difference of two paths of photons, sending the arrival time difference to a signal processing module for calculation, and finally obtaining the position information of the positioning navigation target.

The beam splitter in fig. 2 mainly generates a beam of photons with quantum entanglement characteristics from the entangled photon pair generator to split into two beams, one beam being signal light and the other beam being reference light.

The entangled photon pair generator, the beam splitter, the first satellite ATP system and the second satellite ATP system, the first pyramid reflector and the second pyramid reflector, and the first single photon detector and the second single photon detector in fig. 2 form a photon interferometry unit for generating entangled photon pairs and measuring optical pulse information after two-path photon interference.

The first satellite ATP system and the second satellite ATP system in fig. 2, which have the same structure as the positioning navigation target ATP system and the ground station ATP system, are systems for capturing, tracking, and aiming photons, are used to establish and maintain a quantum communication link through a beacon optical link, and simultaneously realize the emission and reception of photons through the link.

The first pyramid reflector and the second pyramid reflector in fig. 2 are both part of the object to be measured, and are used to return photons emitted from the opposite ATP system.

The two single photon detectors in fig. 2 are used for detecting the single photons, and output digital pulse signals, and the efficiency of detecting the optical signals is directly related to the positioning and navigation accuracy.

The signal receiving module in fig. 2 is mainly a device for receiving the arrival time difference and the quantum satellite coordinates through a beacon optical link and a quantum communication link.

It will be appreciated by those skilled in the art that the relational terms first, second, and the like, as referred to herein, are used solely to distinguish one entity (ATP system, single photon detector) from another entity without necessarily requiring or implying any actual relationship or order between such entities.

In the above system, the first satellite ATP system and the second satellite ATP system of the satellite processing apparatus, the positioning navigation target ATP system of the positioning navigation apparatus, and the ground station ATP system of the ground station processing apparatus all have the same configuration, and the configuration is schematically shown in fig. 3, and mainly includes: the system comprises a coarse tracking module, a fine tracking module, a beacon light module and a control module, wherein the coarse tracking module and the fine tracking module are sequentially connected; the beacon light module consists of a beacon light source, can emit beacon light to the approximate direction of the opposite end between the satellite and the positioning navigation target and between the satellite and the ground station respectively, and is used for establishing a communication link between satellite end processing equipment and ground station processing equipment;

The coarse tracking module comprises: the optical antenna, the two-dimensional turntable, the coarse tracking detector and the coarse tracking controller are used for initially positioning the optical axis and capturing and coarse tracking the beacon light; the optical antenna is used for transmitting and receiving beacon light and quantum light between the satellite and the ground, and capturing between the satellite and the ground is completed by primarily judging the position of the other party according to satellite orbit prediction or the ground approximate range and rotating the optical antenna through the two-dimensional turntable; then the rough tracking detector detects the light spot signal of the beacon light; the coarse tracking controller calculates control quantity by adopting a control algorithm according to the light spot signals, and adjusts the pointing direction of the optical antenna on the two-dimensional turntable so as to introduce the light spot of the beacon light into the view field of the fine tracking module and finish the coarse tracking process;

the fine tracking module comprises: a fine tracking controller, a fine tracking detector, a fast mirror, and a fast mirror sensor for further improving tracking accuracy, including calculating an advanced aiming angle such that an incident optical axis is aligned with an optical axis of the optical antenna; the fine tracking detector converts the beacon light spot signal output by the coarse tracking module into an angle deviation signal, calculates an advanced aiming angle and inputs the angle into the coarse tracking module; the fine tracking controller calculates a corresponding control signal according to the angle deviation signal and a set control algorithm, and the corresponding control signal is used for driving the quick reflector to deflect a certain angle to further compensate the angle error of the coarse tracking module tracking beacon light, so that the fine tracking process is completed; the rapid reflector sensor is used for measuring the deflection angle of the rapid reflector sensor, and transmitting the deflection angle to the signal processing module for calculating the position of the target;

The first satellite ATP system and the second satellite ATP system are arranged on the satellite end processing equipment, the positioning navigation target ATP system and the ground station ATP system are respectively arranged on the positioning navigation equipment and the ground station equipment, the beacon light modules in the two-end ATP systems mutually emit beacon light to establish a quantum communication link, and the quantum communication link is maintained through the coarse tracking module and the fine tracking module. In the positioning navigation system, accurate emission and receiving of quantum light can be realized through the ATP system, and the positioning and navigation precision of the system is greatly improved.

Fig. 4 is a schematic diagram showing the coincidence counting process of two photons generated by the entangled photon pair generator. The coincidence counter is used for carrying out coincidence counting operation on one path of signal light reflected by the measured object and one path of reference light reflected by the ground station pyramid reflector, and outputting time spectrograms corresponding to coincidence counting results under different time delays.

The coincidence counter includes: a nanosecond Delay (DB), a time-to-amplitude converter (TAC) and a multi-channel analyzer (MCA) connected in sequence.

The nanosecond delayer is used for adjusting the time delay value between the digital pulse signals output by the first single photon detector and the second single photon detector, and sending the two paths of adjusted digital pulse signals into the range of the time-width converter as the starting signal and the ending signal.

The smaller the measuring range of the time-amplitude converter is, the higher the resolution is, and according to the time difference value of the input starting pulse and the input ending pulse, the level signals with different amplitudes are output by the time-amplitude converter and are sent into the multichannel analyzer, and the larger the time difference value of the input signals is, the higher the output level is.

The multi-channel analyzer performs coincidence counting measurement analysis on the level signals output by the amplitude converter, and the higher level signals are positioned on larger channel addresses in the multi-channel analyzer, and each channel address has a corresponding coincidence counting result.

Referring to fig. 5, a time spectrogram, which is recorded based on a measurement algorithm and meets the counting result, is subjected to curve fitting, so that a small variation of a time delay value can be obtained, and the accuracy of the system is improved.

In a given acquisition time T, carrying out data acquisition on two paths of level pulse signals with a certain delay time to obtain two paths of time sequences, and calibrating a reference optical path CH1 sequence and a signal optical path CH2 sequence according to different marker bits; (2) taking the data CH2 as a basic sequence, adding a given delay value to each time sequence point of the other path of data CH1

(3) in the given coincidence door width +.>

In the method, two sequences of CH1 and CH2 are subjected to coincidence counting once, and the time delay +.>

The generated coincidence count value->

The method comprises the steps of carrying out a first treatment on the surface of the (4) Obtaining a new delay time according to the set delay increasing step length>

Returning to the step (2) to obtain the current coincidence count value +.>

The method comprises the steps of carrying out a first treatment on the surface of the (5) When the given maximum cycle number is reached, the process of coincidence counting is finished; (6) converting the coincidence count values obtained in all the cycle times into normalized second-order correlation function values to obtain different delay +.>

And its corresponding normalized second order correlation function value->

Discrete points therebetween; (7) discrete points obtained by using least square fitting algorithm>

And performing curve fitting, wherein the abscissa delay value corresponding to the curve peak value is the arrival time difference between the two paths of intertwining quantum light.

The accuracy of coincidence counting in fig. 5 is in the order of femtosecond, which means that whether the entangled photon pair reaches the first single photon detector and the second single photon detector simultaneously can be judged by the time accuracy of femtosecond, and the time accuracy corresponds to the order of micrometers in space, so that the quantum navigation positioning and navigation system achieves the spatial positioning of the order of micrometers on the ground measured object.

The embodiment of the invention also provides a satellite-based quantum positioning navigation method based on a single satellite and a ground station, which is realized based on the satellite-based quantum positioning and navigation system and comprises the following steps:

the first satellite ATP system and the second satellite ATP system respectively send beacon light with the positioning navigation target ATP system and the ground station ATP system, and after scanning alignment, capturing, tracking and aiming are completed, and two quantum communication links are established; meanwhile, a quick reflector sensor of a fine tracking module of the first satellite ATP system measures a two-dimensional turntable of a first quantum communication link between the first satellite ATP system and a positioning navigation target ATP system, and the deflection angle of the quick reflector, the output of a coarse tracking module and the output of the fine tracking module are sent into a signal processing module together to obtain the azimuth angle and the pitch angle of positioning navigation equipment relative to a satellite; the entangled photon pair generator generates two-photon pairs with entangled compression characteristics, and the generated two-path photon quantum light is subjected to beam splitting treatment through the beam splitter; one path of photons is used as signal light and is transmitted to a first cone reflector of positioning navigation equipment along a first quantum communication link established by a first satellite ATP system and a positioning navigation target ATP system, and then the photons return to a first single photon detector which is accessed by a satellite in a primary path; the other path of photons is emitted out through a second satellite ATP system at the satellite end, reaches the ground station ATP system along a second quantum communication link, returns to the satellite end processing equipment through the pyramid reflector 2 of the ground station processing equipment and enters a second single photon detector; obtaining two paths of digital pulse signals from the two paths of single photon detectors; and sending the obtained two paths of digital pulse signals into a coincidence counter to carry out coincidence counting, fitting a curve formed by the pulse numbers obtained by coincidence counting, wherein the abscissa of the peak value on the fitted curve corresponds to the arrival time difference between the satellite and the ground station processing equipment and between the satellite and the positioning navigation equipment, and the actual distance between the satellite and the positioning navigation equipment can be calculated through the arrival time difference and the actual distance between the satellite and the ground station. The signal processing module of the satellite calculates the position of the positioning navigation device on the satellite in a pitching coordinate system according to the azimuth angle and pitch angle of the positioning navigation device relative to the satellite and the actual distance between the satellite and the positioning navigation device, then the position is converted into a geocentric inertial system to obtain the positioning position of the positioning navigation device, and finally the position information is transmitted to the signal receiving module of the positioning navigation device.

When a moving positioning navigation target carrying positioning navigation equipment carries out navigation, in a link between a first satellite ATP system and the positioning navigation target ATP system, quantum light serving as signal light deviates from a beacon optical axis by an advanced aiming angle, the first satellite ATP system calculates the advanced aiming angle through the current speed of the satellite and the positioning navigation equipment, the advanced aiming angle is input into a rough tracking module in the first satellite ATP system for compensation, an optical antenna emits to a first cone reflector in the positioning navigation target ATP system of the positioning navigation equipment, and after the positioning navigation target ATP system calculates the super-front aiming angle, the first cone reflector reflects to the moving satellite by the advanced aiming angle deviating from the beacon optical axis; the second satellite ATP system continuously transmits beacon light with the ground station ATP system, and is used for obtaining a reference light path signal, inputting the reference light path signal and the signal light path into a coincidence counter together after respectively passing through single photon detectors of the respective light paths, capturing, tracking and positioning the moving positioning navigation equipment in real time, and completing the navigation of the moving positioning navigation target.

The devices, functions of the devices, structural relationships between the devices, and the like related to the method have been described in detail in the previous embodiments, so that they will not be described in detail.

In summary, the system and the method of the invention aim, capture and track a positioning navigation device through a single satellite, emit entangled light to perform ranging, obtain the arrival time difference of the entangled light between the satellite and the positioning navigation device and between the satellite and a ground station processing device, and the azimuth angle and pitch angle of the positioning navigation device relative to the satellite, solve the position coordinate of the positioning navigation device under the satellite pitching coordinate system, then perform coordinate conversion, convert the satellite pitching coordinate system to the earth inertia system to obtain the position coordinate of the positioning navigation device, and further determine the position of the positioning navigation target bearing the positioning navigation device; and calculating an advanced aiming angle through a fine tracking module in the ATP system, aiming photons on a moving measured object in advance, capturing, tracking and positioning the moving measured object in real time, and completing navigation of the moving measured object. According to the scheme, a single quantum satellite is adopted, so that a quantum positioning and navigation scheme with the number of satellites smaller than that of three satellites is realized, the number of required quantum satellites and the hardware cost of a quantum positioning system are reduced, the ground station is utilized to reduce the atmospheric delay distance error of a ranging link, and the accuracy of the positioning and navigation scheme is further improved.

The foregoing is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the scope of the present invention should be included in the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims. The information disclosed in the background section herein is only for enhancement of understanding of the general background of the invention and is not to be taken as an admission or any form of suggestion that this information forms the prior art already known to those of ordinary skill in the art.

Claims

1. A satellite-based quantum positioning navigation system based on a single satellite and a ground station, comprising:

the satellite terminal processing equipment is arranged on a single satellite, and can respectively send beacon light with the positioning navigation equipment and the ground station processing equipment to establish a first quantum communication link and a second quantum communication link, and the azimuth angle and the pitch angle of the positioning navigation equipment relative to the single satellite are calculated according to the information of the first quantum communication link; the two-photon pair with entanglement compression characteristics can be generated and split to generate a first path of quantum light signal and a second path of quantum light signal, the two paths of quantum light signals are respectively communicated with the positioning navigation device and the ground station processing device through two quantum communication links to obtain two paths of digital pulse signals, the arrival time difference between a single satellite and the ground station processing device and the arrival time difference between the single satellite and the positioning navigation device are obtained according to the two paths of digital pulse signals, the actual distance between the single satellite and the positioning navigation device is calculated through the arrival time difference and the actual distance between the single satellite and the ground station processing device, the position of the positioning navigation device under a satellite pitching coordinate system is calculated according to the azimuth angle and pitch angle of the positioning navigation device relative to the single satellite and the actual distance between the single satellite and the positioning navigation device, the position is converted to a ground center inertial system to obtain the position of the positioning navigation device, and the ground position is sent to the positioning navigation device for positioning; the advanced aiming angle can be calculated through the current speed of the single satellite and the current speed of the positioning navigation equipment, the advanced aiming angle is used as tracking compensation to be sent to the positioning navigation equipment, the optical signals reflected by the advanced aiming angle are received by the positioning navigation equipment, coincidence counting is carried out in combination with the reference optical path signals established by the ground station processing equipment, so that the mobile positioning navigation equipment is subjected to capturing tracking and real-time positioning, and the navigation of the mobile positioning navigation equipment is completed;

the positioning navigation equipment is in quantum optical communication with the satellite terminal processing equipment, can mutually send beacon light with the satellite terminal processing equipment, and establishes a first quantum communication link so that the satellite terminal processing equipment calculates an azimuth angle and a pitch angle of the positioning navigation equipment relative to a single satellite according to the information of the first quantum communication link; and in a static state, receiving a first path of quantum light signal sent by the satellite terminal processing equipment and reflecting the first path of quantum light signal back to the satellite terminal processing equipment for processing so as to determine the position of the positioning navigation equipment, and receiving the positioning position of the positioning navigation equipment sent by the satellite terminal processing equipment to realize positioning; and in a moving state, receiving a first path of optical signal sent by the satellite processing equipment, reflecting the first path of optical signal to the satellite processing equipment of the moving single satellite according to an advanced aiming angle deviated from a beacon optical axis, processing the first path of optical signal by the satellite processing equipment, and carrying out capturing tracking and real-time positioning on the moving positioning navigation equipment by combining with a reference optical path signal to finish the navigation of the moving positioning navigation equipment.

2. The satellite-based quantum positioning navigation system of claim 1, wherein the satellite-side processing device comprises:

3. The satellite-based quantum positioning navigation system based on a single satellite and a ground station of claim 2, wherein the first satellite ATP system and the second satellite ATP system are identical in composition, each comprising:

4. A satellite based quantum positioning navigation system based on a single satellite and a ground station as claimed in claim 3, wherein the coarse tracking module comprises: the device comprises an optical antenna, a two-dimensional turntable, a coarse tracking detector and a coarse tracking controller; wherein,

The optical antenna is arranged on the two-dimensional turntable and is positioned at the output end of the beam splitter, and is used for transmitting and receiving beacon light and quantum light signals between the satellite and the ground equipment, and the capturing of the beacon light and the quantum light signals between the satellite and the ground equipment is completed by primarily judging the opposite side position according to the satellite orbit forecast or the range of the ground equipment, and rotating the optical antenna through the two-dimensional turntable;

the coarse tracking detector is in communication connection with the coarse tracking controller, can detect the light spot signal of the beacon light and sends the light spot signal to the coarse tracking controller;

5. The satellite-based quantum positioning navigation system based on single satellite and ground station of claim 4, whereinThe signal processing module calculates the azimuth angle of the positioning navigation device relative to a single satellite according to the information of a first quantum communication link output by the first satellite ATP system according to the following formula

And pitch angle->

The formula is:

；

wherein ,

、/>

、/>

Respectively obtaining deflection angle values to be compensated for a pitching axis and an azimuth axis of the two-dimensional turntable;

、/>

、/>

6. The satellite-based quantum positioning navigation system of any of claims 2-5, wherein the coincidence counter comprises: a nanosecond delayer, a time-amplitude converter and a multichannel analyzer which are connected in sequence; wherein,

7. The satellite-based quantum positioning navigation system based on a single satellite and a ground station of any one of claims 2-5, wherein the positioning navigation device comprises:

Positioning a navigation target ATP system, a first cone reflector and a signal receiving module; wherein,

the positioning navigation target ATP system is respectively connected with the satellite end processing equipment and the first pyramid reflector in an optical communication way, can establish a first quantum communication link with the first satellite ATP system of the satellite end processing equipment, receives a first path of quantum optical signals emitted by the first satellite ATP system of the satellite end processing equipment and sends the first path of quantum optical signals to the first pyramid reflector;

the signal receiving module is in communication connection with the signal processing module of the satellite terminal processing equipment and is used for receiving the position coordinates of the positioning navigation target of the bearing positioning navigation equipment.

8. The satellite-based quantum positioning navigation system of any of claims 2-5, wherein the ground station processing device comprises:

a ground station ATP system and a second pyramid reflector; wherein,

the ground station ATP system is respectively connected with the satellite terminal processing equipment and the second pyramid reflector in an optical communication way, can establish a second quantum communication link with the second satellite ATP system of the satellite terminal processing equipment, receives a second path of quantum optical signals emitted by the second satellite ATP system of the satellite terminal processing equipment and sends the second path of quantum optical signals to the second pyramid reflector;

9. A satellite-based quantum positioning navigation method based on a single satellite and a ground station, characterized in that the system according to any one of claims 1-8 is adopted, comprising the following steps:

10. The satellite-based quantum positioning navigation method based on a single satellite and a ground station according to claim 9, wherein the satellite-side processing device calculates the actual distance R between the single satellite and the positioning navigation device by the arrival time difference and the actual distance between the single satellite and the ground station processing device in the following manner _sgt The method comprises the following steps:

；

wherein C is the speed of light;

to the ground for a single satelliteArrival time differences between the surface station processing devices and between a single satellite to the positioning navigation device; r is R _sgs For passing the position coordinates S (x _s0 ，y _s0 ，z _s0 ) And the position coordinates G (x _g0 ，y _g0 ，z _g0 ) The actual distance R between the single satellite and the ground station processing equipment _sgs Calculated according to the following formula:

；

；

solving the position (r) of the positioning navigation device on the satellite under the pitching coordinate system _sg-x ,r _sg-y ,r _sg-z )；

Based on the position (r) of the positioning and navigation device in the pitch coordinate system on the satellite _sg-x ,r _sg-y ,r _sg-z ) And knowing the satellite current position coordinates S (x _s0 ，y _s0 ，z _s0 ) The listed positioning locations (x _g ,y _g ,z _g ) Equation (x) _s0 -x _g ,y _s0 -y _g ,z _s0 -z _g )=D ^-1 ×(r _sg-x ,r _sg-y ,r _sg-z ) The following solution equation is derived to locate the position (r) of the navigation device in the pitch coordinate system on the satellite _sg-x ,r _sg-y ,r _sg-z ) Conversion to a geocentric inertial system yields a position location (x) of the positioning navigation device _g ,y _g ,z _g ) The solution equation is:

；

wherein ,S(x_s0 ，y _s0 ，z _s0 ) The current position coordinates of satellites known under the geocentric inertial system; e (E) ₁ 、A ₁ 、R _sgt Respectively positioning azimuth angle, pitch angle and actual distance of the navigation equipment relative to the satellite; d is a coordinate transformation matrix from the geocentric inertial system to the satellite pitch coordinate system, where the coordinate transformation matrix D is expressed as:

；

；

in the coordinate transformation matrix D, the six parameters of the satellite orbit are used: inclination angle i of the track, ascending intersection point right through omega and near-place radial angle omega; set the geocenter inertia Ox _i y _i z _i The unit vector of the three directions in the system is x _l 、y _l 、z ₁； wherein ,y_l And x _l 、z ₁ Forms a right hand system and is provided with a satellite upper pitching coordinate system Ox _s y _s z _s Unit vector x of three directions in (3) _s 、y _s 、z _s； wherein ,z_s And x _s 、y _s Forming a right hand system; the geocentric inertial system is converted into a satellite on-board pitching coordinate system, and the coordinate system is regarded as being firstly around z ₁ Direction is rotated by omega angle, and then is wound around x _l Direction rotates by an angle of i, and finally winds the current z ₁ And (3) rotating the direction by omega angle to obtain the satellite upper pitching coordinate system.