CN103675872B - Based on positioning system and the localization method thereof in GNSS signal source - Google Patents

Abstract

The present invention relates to a positioning system based on GNSS signal sources, comprising: a plurality of GNSS signal sources and at least one GNSS signal receiver, each GNSS signal source is pre-arranged at a fixed position in a target area for simulating and simultaneously transmitting 4 Satellite signals of one or more GNSS navigation satellites; the GNSS signal receiver is used to receive satellite signals transmitted by at least one GNSS signal source, and calculate its own position according to the satellite signals. The present invention also relates to a positioning method of the positioning system based on the GNSS signal source.

Description

Positioning system and its positioning method based on GNSS signal source

technical field

The invention relates to a wireless positioning system and method, in particular to a positioning system and method based on a GNSS signal source.

Background technique

In the prior art, among various radio positioning technologies, the Global Navigation Satellite System (Global Navigation Satellite System, GNSS) is the most basic means, and it is the full name of all navigation satellite systems, mainly including the Global Positioning System (Global Positioning System, GPS) of the United States at present. , Russia's Global Navigation Satellite System (Global Navigation Satellite System, GLONASS), Europe's Galileo system (Galileo), and China's Beidou (Compass). The basic working principle of the GNSS receiver is: receive the radio signal sent by the navigation satellite and extract the pseudo-moment, and calculate its own position in the geographic coordinate system according to more than 4 pseudo-moments. The common solution algorithm is least squares Multiplication and Kalman filtering methods.

The above-mentioned space-based navigation system has the advantages of all-weather global coverage, but also has the disadvantage of being difficult to achieve coverage and positioning in indoor and urban canyon scenes. In order to overcome the above problems, people have invented a hybrid positioning method that integrates ground network and space-based network, a positioning method based on inter-node ranging, and a positioning technology using similar IEEE802.11 series wireless local area networks. However, whether it is a hybrid positioning method based on the integration of ground network and space-based network, a positioning method based on inter-node ranging, or a positioning technology using similar IEEE802.11 series wireless local area networks, special positioning receiving equipment and software support are required. Therefore, the structure of the above-mentioned positioning technology is relatively complicated and the positioning accuracy is low.

Contents of the invention

In view of this, it is indeed necessary to provide a positioning system and a positioning method thereof which are simple and have high positioning accuracy.

A positioning system based on GNSS signal sources, comprising: a plurality of GNSS signal sources and at least one GNSS signal receiver, each GNSS signal source is pre-arranged at a fixed position in a target area for simulating and simultaneously transmitting 4 or 4 Satellite signals of more than one GNSS navigation satellite; the GNSS signal receiver is used to receive satellite signals transmitted by at least one GNSS signal source, and calculate its own position according to the satellite signals.

A positioning method based on a GNSS signal source positioning system, wherein the GNSS signal source positioning system includes a plurality of GNSS signal sources and at least one GNSS signal receiver, and each GNSS signal source is pre-arranged at a fixed position in a target area , wherein, the positioning method includes the following steps: each GNSS signal source simulates and simultaneously transmits satellite signals of 4 or more GNSS navigation satellites; and, the GNSS signal receiver receives at least one GNSS signal source transmitted satellite signal, and determine its own position according to the satellite signal

Compared with the prior art, the GNSS signal receiver in the positioning system based on the GNSS signal source provided by the present invention can perform positioning without modification, and the positioning system based on the GNSS signal source also has higher positioning accuracy, And the error is not more than 12 meters. In addition, the positioning method of the positioning system based on the GNSS signal source provided by the present invention also has the characteristics of being simple and easy to apply.

Description of drawings

FIG. 1 is a schematic diagram of a scenario of a positioning system based on a GNSS signal source provided by a first embodiment of the present invention.

FIG. 2 is a schematic diagram of an overlapping area formed by satellite signals transmitted by two GPS signal sources in the positioning system based on GNSS signal sources according to the first embodiment of the present invention.

Fig. 3 is a flow chart of grouping based on pseudorange in the positioning method of the positioning system based on the GNSS signal source provided by the first embodiment of the present invention.

Fig. 4 is a schematic diagram of a scenario of a positioning system based on a GNSS signal source provided by a second embodiment of the present invention.

5 is a schematic diagram of an overlapping area formed by position signals transmitted by two GPS signal sources in a positioning system based on GNSS signal sources according to a second embodiment of the present invention.

Description of main component symbols

Positioning system based on GNSS signal source 100; 200 GPS signal source ₁₀ ; ₂₀ ; A ₁₁ ; A ₁₂ ; A ₁₃ ; A ₁₄ ; A ₁₅ ; A ₁₆ ; A ₁₇ ; A ₁₈ ; _{A 19 ;} A ₂₁ ; A ₂₂ ; ₂₇ ;A ₂₈ ;A ₂₉ GPS signal receiver 12 central server 14 coverage area B ₁ ; B ₂ ; B ₄ ; B ₅ overlapping area B ₃ ; B ₆ distance d ₁ ; d ₂ ; d ₃ ; d ₄

The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings.

detailed description

The invention provides a positioning system and method based on a Global Navigation Satellite System (Global Navigation Satellite System, GNSS) signal source. The global navigation satellite system includes the Global Positioning System (Global Positioning System, GPS) of the United States, the Global Navigation Satellite System (Global Navigation Satellite System, GLONASS) of Russia, the Galileo system (Galileo) of Europe, and the Beidou (Compass) of China. The embodiment of the present invention only uses the GPS signal source as an example to describe the positioning system and method based on the GNSS signal source provided by the present invention in detail.

Referring to FIG. 1 , the first embodiment of the present invention provides a positioning system 100 based on GNSS signal sources, including: a plurality of GPS signal sources 10 and at least one GPS signal receiver 12 . It can be understood that the signal source and the signal receiver need to match each other, for example, when using the Compass signal source, a matching Compass signal receiver needs to be used.

Each GPS signal source 10 is pre-arranged at a fixed position in a target area for simulating satellite signals of 4 or more GPS navigation satellites, and simultaneously sending the multiple satellite signals to the GPS signal receiver 12. The target area may be a building interior or an urban canyon. In this embodiment, the target area is inside a building, and the building includes multiple rooms. The fixed position means that the longitude, latitude and altitude of the GPS signal source 10 are fixed. The number of the GPS signal sources 10 can be selected according to different positioning accuracies. In this embodiment, 9 GPS signal sources 10 are included, and each GPS signal source 10 is respectively set in each room. For the convenience of description, the GPS signal sources 10 are sequentially named as GPS signal sources A ₁₁ , A ₁₂ , A ₁₃ , A ₁₄ , A ₁₅ , A ₁₆ , A ₁₇ , A ₁₈ and A ₁₉ . The satellite signal simulated by the GPS signal source 10 is, , wherein, i is a GPS satellite identifier, and i=0,1,2,3,...,31; M is a set of satellite identifiers of satellite signals simulated by the GPS signal source 10, for example, may be {0,1 ,2,3,4} etc.; A _i is the signal amplitude of satellite i; PN _i (t) is the spreading code of satellite i; w _c is the carrier frequency; f is the random phase; t is the time.

In order to reduce the mutual interference between GPS signal sources 10 that are relatively close to each other, the signal of each GPS signal source 10 can only cover a given area by controlling the transmission power of each GPS signal source 10 . In this embodiment, the signal of each GPS signal source 10 basically covers only one room. Since the actual coverage area of the signals of the GPS signal sources 10 can only be controlled by the antenna orientation and the adjustment of the transmission power, it is inevitable that the coverage areas of the GPS signal sources 10 overlap. Referring to FIG. ₂ , B1 is the coverage area _of the GPS signal source _A11 , B2 is the coverage area of the GPS signal source _A12 , and _B3 is the overlapping area of the GPS signal sources _A11 and _A12 . In order to reduce the interference between the GPS signal sources _A11 and _A12 , the GPS signal sources _A11 and _A12 can transmit satellite signals with different spreading codes. In this embodiment, the satellite signal simulated and transmitted by GPS signal source A ₁₁ is defined as , wherein, M ₁₁ is the set of satellite identifications simulated and transmitted by GPS signal source A ₁₁ ; the satellite signal simulated and transmitted by GPS signal source A ₁₂ can be defined as , wherein, M ₁₂ is a set of satellite identities simulated and transmitted by GPS signal source A ₁₂ ; and the GPS signal sources A ₁₁ and A ₁₂ respectively simulate and transmit satellite signals of different satellites, that is, M ₁₁ and M ₁₂ The intersection is an empty set, for example, when the set of satellite identifications simulated and transmitted by the GPS signal source A ₁₁ is M ₁₁ =﹛0,1,2,3,4﹜, the GPS signal source A ₁₂ simulates The set M ₁₂ of satellite identities to be transmitted cannot contain any one of ﹛0, 1, 2, 3, 4﹜.

The GPS signal source 10 can be further integrated with an IEEE802.11 wireless router and other wireless communication devices to increase the functional density of the positioning system 100 based on the GNSS signal source, reduce costs, and realize the integration of communication and positioning.

The GPS signal source 10 can be realized by means of software radio or ASIC. In this embodiment, the GPS signal source 10 is realized by an ASIC.

The GPS signal receiver 12 is used for receiving at least one satellite signal transmitted by the GPS signal source 10, and performing calculation according to the satellite signal, so as to obtain a satellite signal. It can be understood that the position obtained through calculation by the GPS signal receiver 12 is the position of the GPS signal source 10 corresponding to the received satellite signal. For example, when the GPS signal receiver 12 receives the satellite signal transmitted by the GPS signal source A ₁₁ , and calculates the position according to the satellite signal, it is actually the position of the GPS signal source A ₁₁ itself.

There is an error between the position calculated by the GPS signal receiver 12 and the true position of the GPS signal receiver 12, and the size of the error depends on the coverage of the GPS signal source 10 and the relationship between the GPS signal receiver 12 and the GPS signal receiver 12. The distance difference of the GPS signal source 10 . In indoor positioning, generally one GPS signal source 10 covers one room, and at this time, its error is not more than 12 meters.

Due to the development of micro-electro-mechanical systems, inertial navigation elements such as gyroscopes, accelerometers and magnetometers have become standard configurations of mobile devices. Therefore, the GPS signal receiver 12 can further integrate the inertial navigation elements, thereby further improving positioning results.

Please also refer to FIG. 1 , the positioning system 100 based on GNSS signal source may further include a central server 14 for receiving the geographic location information of the GPS signal receiver 12 for tracking and monitoring by others. The GPS signal receiver 12 can transmit the geographic location information to the central server 14 through a wireless network, such as the mobile Internet, for others to track and monitor.

The positioning method of the positioning system 100 based on the GNSS signal source comprises the following steps:

S1: Each GPS signal source 10 simulates and simultaneously transmits satellite signals of 4 or more GPS navigation satellites;

S2: The GPS signal receiver 12 receives satellite signals transmitted by at least one GPS signal source 10, and determines its own position according to the satellite signals.

In step S2, when the GPS signal receiver 12 only receives a satellite signal transmitted by a GPS signal source 10, the GPS signal receiver 12 can pass the existing autonomous integrity check according to the satellite signal The algorithm (ReceiverIntegrityAutonomousMonitoring, RAIM) solves the satellite signal.

Please also refer to Fig. 2, when the GPS signal receiver 12 receives the satellite signals transmitted by the two GPS signal sources A ₁₁ and A ₁₂ , due to the near-far effect, signals of different spreading codes still appear interference. Now, for the GPS signal receiver 12, there are two situations:

A special case is that due to the near-far effect, the signal of GPS signal source A ₁₂ is completely interfered by GPS signal source A ₁₁ (or the signal of GPS signal source A ₁₁ is completely interfered by GPS signal source A ₁₂ ), the GPS signal receiver 12 Only the signal of GPS signal source A ₁₁ (GPS signal source A ₁₂ ) can be received. At this time, the position calculated by the GPS signal receiver 12 is the geographic location of GPS signal source A ₁₁ (GPS signal source A ₁₂ ), Therefore, the actual distance between the GPS signal receiver 12 and the GPS signal source A ₁₁ (GPS signal source A ₁₂ ) is the positioning error.

In another case, the powers arriving at the GPS signal receiver 12 have little difference, and their signals can all be received by the GPS signal receiver 12 . At this time, since the clocks of GPS signal sources A ₁₁ and A ₁₂ are not synchronized, if the position is calculated by the existing RAIM algorithm, the position obtained by the GPS signal receiver 12 is neither the position of GPS signal source A ₁₁ , is not the position of the GPS signal source _A12 , but a random position that is far from both the GPS signal sources _A11 and _A12 . The accurate position of described GPS signal receiver 12 can be obtained by the following methods:

S21: The GPS signal receiver 12 groups all the satellites simulated by the GPS signal source 10 to obtain multiple groups G _j , where j is the group number, j=0, 1, 2,...;

S22: The GPS signal receiver 12 calculates once according to the satellite information in each group G _j , obtains the position information of each GPS signal source corresponding to each group G _j , and forms a set P;

S23: The GPS signal receiver 12 calculates the average carrier-to-noise ratio corresponding to the satellite signal in each group G _j , and calculates the GPS signal receiver 12 to correspond to each group G _j according to the carrier-to-noise ratio the distances of the GPS signal sources 10, forming the set D; and

S24: The GPS signal receiver 12 obtains its own position according to the set P and the set D.

In step S21, it is assumed that the simulated known position of satellite i is , the position of the GPS signal receiver 12 is , the time difference between the GPS signal receiver 12 and the clock of satellite i is t _R , then the pseudorange corresponding to satellite i The expression is: ,in for the speed of light. Please refer to FIG. 3, the plurality of groups G _j can be obtained by a RAIM algorithm based on pseudorange grouping, and the RAIM algorithm based on pseudorange grouping includes the following steps:

S211: Generate a satellite set S for all satellites i simulated by the GPS signal source 10 according to their satellite identifiers;

S212: Given the initial position of the GPS signal receiver 12, and select a satellite as the reference satellite r, set the reference time of the GPS signal receiver 12, and calculate the reference pseudorange , and set a reference threshold T _h ;

S213: Calculate the pseudorange corresponding to the next satellite i in the satellite set S according to the initial position and reference time of the GPS signal receiver 12 ,like , select satellite i;

S214: Repeat step S213 until there is no satellite in the satellite set S that satisfies , divide the reference satellites and selected satellites into groups G _j ; and

S215: Delete the satellites in G _j from the set S, if the set S is not empty, set j=j+1, return to step S212, otherwise the algorithm ends.

Please refer to FIG. 2, in step S211, it is assumed that the satellite signal simulated by the GPS signal source A ₁₁ includes satellite {0,1,2,3,4,5}, and the satellite signal simulated by the GPS signal source A ₁₂ Contains satellites {6,7,8,9,10}. The GPS signal receiver 12 is located in the overlapping area B ₃ of the GPS signal source A ₁₁ and the A ₁₂ , and in the overlapping area B ₃ the GPS signal receiver 12 can receive the GPS signal source A ₁₁ and the A 12 ₁₂ The data of all the satellites simulated and launched, therefore, the satellite set S={0,1,2,3,4,5,6,7,8,9,10} is generated.

In step S212, the initial location of the GPS signal receiver 12 can be set as {0,0,0} or a known historical location. In this embodiment, the initial position of the GPS signal receiver 12 is set as {0,0,0}. The reference time of the GPS signal receiver 12 can be equal to the signal transmission time of the reference satellite r, or a constant can be added on the basis of the signal transmission time of the reference satellite r. In this embodiment, the reference time of the GPS signal receiver 12 is set to be equal to the signal transmission time of the reference satellite r, that is, t _R =0. In addition, in order not to lose generality and facilitate understanding, the reference pseudorange can be obtained km (in the actual system, the distance between each satellite and the GPS signal receiver 12 is in this order of magnitude, and they are not the same, therefore, it does not affect the actual operation of the RAIM algorithm). The reference threshold _Th can be selected according to actual needs. In this embodiment, the reference threshold T _h =10000km.

In steps S213 and S214, the satellite signals of the satellites 0, 1, 2, 3, 4, 5 are all transmitted by the GPS signal source A ₁₁ at the same time, that is, the satellites 0, 1, 2, 3, 4, and 5 have the same launch time, all of which are t ₁ ; and the satellite signals of the satellites 6, 7, 8, 9, and 10 are all launched by the GPS signal source A ₁₂ at the same time, that is, the The launch times of satellites 6, 7, 8, 9, and 10 are also the same, all of which are t ₂ ; but t ₂ is quite different from t ₁ , and will change every time it is calculated. Here, it is randomly assumed that t ₁ -t ₂ =1s . Assuming that satellite 0 is used as the reference satellite r, it can be calculated that the pseudo-ranges of satellites 1, 2, 3, 4, and 5 are all 27,200 km, while the pseudo-ranges of satellites 6, 7, 8, 9, and 10 are 327,200 km. Thus, in the first round of calculation, satisfy The first group of G ₀ ={0,1,2,3,4,5}.

In step S215, G ₀ ={0,1,2,3,4,5} is deleted from the satellite set S to obtain a set S'={6,7,8,9,10}. Since the set S'={6,7,8,9,10} is not empty, set j=j+1=1, and repeat step S212.

According to the above algorithm, satellite 6 is further selected as the reference satellite r, and the reference time of the GPS signal receiver 12 is set to be the same as the launch time of satellite 6. , it can be known that the reference pseudorange =27200km, at this time the pseudo-ranges of satellites 7, 8, 9, and 10 are also 27200km, all satisfying , so the second group G ₁ ={6,7,8,9,10} is obtained. Further, delete G ₁ ={6,7,8,9,10} from S, and obtain S'' as an empty set. Since the empty set S'' is obtained in the second round of calculation, the algorithm ends and outputs groups G ₀ ={0,1,2,3,4,5} and G ₁ ={6,7,8, 9,10}.

Because the same GPS signal source 10 transmits all satellite signals at the same time, there is a large gap in the transmission time between different GPS signal sources 10, and a difference of 1 second in the transmission time corresponds to a pseudo-range difference of 300,000 kilometers, while the normal The pseudo-range difference between different satellites is within 20,000 kilometers. Therefore, the number of groups G _j finally obtained according to the RAIM algorithm based on pseudorange grouping generally corresponds to the number of GPS signal sources 10 . In FIG. 2 , the GPS signal receiver 12 can obtain two groups G ₀ and G ₁ , wherein the group G ₀ corresponds to the GPS signal source A ₁₁ , and G ₁ corresponds to the GPS signal source A ₁₂ .

In step S22, the GPS signal receiver 12 can calculate once respectively according to the satellite information in the groups G ₀ and G ₁ to obtain the position P ₁₁ ={x ₁₁ of the GPS signal source A ₁₁ corresponding to G ₀ , y ₁₁ , z ₁₁ } and the position P ₁₂ of the GPS signal source A ₁₂ corresponding to G ₁ ={x ₁₂ , y ₁₂ , z ₁₂ }. Therefore, a set P={P ₁₁ ,P ₁₂ } is obtained.

In step S23, in GPS, the carrier-to-noise ratio is an indicator for evaluating the quality of the received signal, reflecting the path attenuation in the signal transmission process, so it can be used to estimate the distance between the GPS signal receiver 12 and the GPS signal source 10. distance between. The method of estimating the distance by carrier-to-noise ratio is the same as the method of calculating the distance by using the signal-to-noise ratio and the signal strength indication of the GPS signal receiver 12, and there are many published methods in the literature, so they will not be repeated here. In this embodiment, it is assumed that the distance is short if the carrier-to-noise ratio is strong, and the distance is long if the carrier-to-noise ratio is high. The noise does not change with the distance, and the useful signal attenuates according to the power of 2-6 with the distance. Please refer to Fig. 2 together, described GPS signal receiver 12 can solve separately according to the carrier-to-noise ratio in group _G0 and _G1 , thereby obtain described GPS signal receiver ₁₂ and the distance of described GPS signal source A11 d ₁ and the distance d ₂ of the GPS signal source A ₁₂ . Therefore, a set D={d ₁ ,d ₂ } is obtained.

In step S23, the GPS signal receiver 12 can obtain its own position P _B3 ={x _B3 , y _B3 , z _B3 } according to the geometric method or the least square method. In this example, , as well as .

Referring to FIG. 4 , the second embodiment of the present invention provides a positioning system 200 based on GNSS signal sources, including: a plurality of GPS signal sources 20 and at least one GPS signal receiver 12 .

The positioning system 200 based on the GNSS signal source is basically the same as the positioning system 100 based on the GNSS signal source in the first embodiment of the present invention, the difference is that the GPS signal source 20 directly embeds its own geographic location into its In the navigation message of each satellite signal that is simulated and transmitted. Therefore, the GPS signal receiver 12 can directly extract the geographic location in the navigation text without performing calculations, so as to obtain the location of the GPS signal source 20 . Therefore, the positioning system 200 based on the GNSS signal source can quickly obtain its own geographic location.

A general GPS navigation message consists of 5 subframes, which are sent repeatedly. Therefore, the geographic location of the GPS signal source 20 itself can be placed in the spare area of the GPS message, such as pages 1, 6, 11, 12, 13, 14, 15, 16 and 19-24 of the 4th subframe; Or fill the geographic location of the GPS signal source 20 itself on all pages of all the 4th and 5th subframes. The advantage of doing this is that the GPS signal receiver 12 can quickly locate. For the Beidou second-generation system, all almanac-related messages can also be filled with the geographic location of the GPS signal source 20 itself.

Since each GPS signal source 20 basically covers a room, and all ephemeris accounts for 2 subframes in the 5 subframes of the GPS navigation message, therefore, in order to further serve the needs of indoor positioning, the location where the GPS signal source 20 can be further placed The floor, room number and its own geographical location are filled into all almanac-related messages to replace the original almanac-related messages. Furthermore, the navigation map can also be broadcast together with the almanac-related messages.

The positioning method of the positioning system 200 based on the GNSS signal source comprises the following steps:

S3: Each GPS signal source 20 simultaneously transmits satellite signals of 4 or more GPS navigation satellites, and the navigation message of each satellite signal is embedded with the geographic location of the GPS signal source 20 itself; and

S4: The GPS signal receiver 12 receives the satellite signal, and directly extracts the geographic location of the GPS signal source 20 itself.

In step S4, when the GPS signal receiver 12 only receives the satellite signal transmitted by one GPS signal source 20, the GPS signal receiver 12 can directly extract and obtain the geographic location of the GPS signal source 20 itself.

Please also refer to FIG. 5 , when the GPS signal receiver 12 receives the satellite signals transmitted by the two GPS signal sources A ₂₁ and A ₂₂ , interference will occur due to the near-far effect. Now, for the GPS signal receiver 12, there are two situations:

A special case is that due to the near-far effect, the satellite signal of GPS signal source A ₂₂ is completely interfered by GPS signal source A ₂₁ (or the satellite signal of GPS signal source A ₂₁ is completely interfered by GPS signal source A ₂₂ ), and the GPS signal receiving The receiver 12 can only receive the satellite signal of the GPS signal source A ₂₁ (GPS signal source A ₁₂ ), at this time, the self-position obtained by the GPS signal receiver 12 is the GPS signal source A ₂₁ (GPS signal source A ₂₂ ) Therefore, the actual distance between the GPS signal receiver 12 and the GPS signal source A ₂₁ (GPS signal source A ₂₂ ) is the positioning error.

In another case, the powers arriving at the GPS signal receiver 12 have little difference, and their satellite signals can all be received by the GPS signal receiver 12 . At this time, since the clocks of the GPS signal sources A ₂₁ and A ₂₂ are not synchronized, the position obtained by the GPS signal receiver 12 is neither the position of the GPS signal source A ₂₁ nor the position of the GPS signal source A ₂₂ , Rather, it is a random position that is far from both GPS signal sources A ₂₁ and A ₂₂ . The accurate position of described GPS signal receiver 12 can be obtained by the following methods:

S41: According to the position information of the navigation message in each satellite signal, group all the simulated satellites into groups to obtain multiple groups G _j , j is the group number, j=0,1,2,...;

S42: Form the geographic location of each GPS signal source 20 into a set P;

S43: The GPS signal receiver 12 calculates the average carrier-to-noise ratio of satellite signals in each group G _j , and calculates the GPS signal corresponding to each group G _j from the GPS signal receiver 12 according to the carrier-to-noise ratio the distances of the sources 20, forming the set D; and

S44: Obtain the own position according to the set P and the set D.

In step S41, since the geographic locations embedded in the navigation message in the satellite signal transmitted by the GPS signal source A ₂₁ are all the same, that is, all are: {x ₂₁ , y ₂₁ , z ₂₁ }, therefore, the group G ₀ is obtained; and The geographic location embedded in the navigation message in the satellite signal transmitted by the GPS signal source A ₂₂ is also the same, that is, both are: {x ₂₂ , y ₂₂ , z ₂₂ }, therefore, the group G ₁ is obtained.

In step S42, the GPS signal receiver 12 directly extracts and obtains the position P ₂₁ ={x ₂₁ , y ₂₁ , z ₂₁ } of the GPS signal source A ₂₁ and the position P ₂₂ of the GPS signal source A ₂₂ ={x ₂₂ ,y ₂₂ ,z ₂₂ }. Therefore, a set P={P ₂₁ , P ₂₂ } is obtained.

In step S43, the GPS signal receiver 12 can separately calculate according to the carrier-to-noise ratio in each group _G0 and _G1 , thereby obtaining the distance from the GPS signal receiver ₁₂ to the GPS signal source A21 d ₃ and the distance d ₄ of the GPS signal source A ₂₂ . Therefore, a set D={d ₃ ,d ₄ } is obtained.

In step S43, the GPS signal receiver 12 can obtain its own position P _B6 ={x _B6 , y _B6 , z _B6 } according to the geometric method or the least square method. In this example, , as well as .

In addition, those skilled in the art can also make other changes within the spirit of the present invention. Of course, these changes made according to the spirit of the present invention should be included within the scope of protection claimed by the present invention.

Claims (5)

1. A positioning method based on a GNSS signal source positioning system, wherein said GNSS signal source positioning system includes a plurality of GNSS signal sources and at least one GNSS signal receiver, and each GNSS signal source is pre-arranged in a target area A fixed position, wherein the positioning method comprises the following steps: S1: Each GNSS signal source simulates and simultaneously transmits satellite signals of 4 or more GNSS navigation satellites; and S2: The GNSS signal receiver receives satellite signals transmitted by at least one GNSS signal source, and determines its own position according to the satellite signals; when the GNSS signal receiver receives satellite signals transmitted by at least two GNSS signal sources, And when the satellite signals transmitted by the GNSS signal source interfere with each other, the GNSS signal receiver determines its own position by the following method: S21: Group all the satellites simulated by the GNSS signal source into groups, and obtain multiple groups Gj through autonomous integrity detection, where j is the group number, j=0,1,2,...; S22: Calculate once according to the satellite information in each group Gj, obtain the position of each GNSS signal source corresponding to each group Gj, and form a set P; S23: Calculate the average carrier-to-noise ratio corresponding to the satellite signal in each group Gj, and calculate the distance from the GNSS signal receiver to the GNSS signal source corresponding to each group Gj according to the carrier-to-noise ratio, forming a set D; as well as S24: Obtain the own position according to the set P and the set D. 2. The positioning method according to claim 1, wherein the method for obtaining multiple groups Gj through autonomous integrity detection comprises the following steps: S211: Generate a satellite set S for all satellites i simulated by the GNSS signal source according to their satellite identifiers; S212: Given the initial position of the GNSS signal receiver, and selecting a satellite as the reference satellite r, setting the reference time of the GNSS signal receiver, calculating the reference pseudorange ρ _r , and setting a reference threshold T _h ; S213: Calculate the pseudorange corresponding to the next satellite i in the satellite set S according to the initial position and reference time of the GNSS signal receiver like Then satellite i is selected; S214: Repeat step S213 until there is no satellite in the satellite set S that satisfies Partitioning the reference satellites and the selected satellites into groups G _j ; and S215: Delete the satellites in G _j from the set S, if the set S is not empty, set j=j+1, return to step S212, otherwise the algorithm ends. 3. The positioning method according to claim 2, wherein the reference time of the GNSS signal receiver is set to be equal to the signal transmission time of the reference satellite r, the reference pseudorange ρ _r =27200km, and the reference threshold Th=10000km. 4. The positioning method according to claim 1, wherein the GNSS signal receiver obtains its own position according to the set P and the set D and through a geometric method or a least square method. 5. A positioning method based on a GNSS signal source positioning system, wherein said GNSS signal source positioning system includes a plurality of GNSS signal sources and at least one GNSS signal receiver, and each GNSS signal source is pre-arranged in a target area A fixed position, wherein the positioning method comprises the following steps: S1: Each GNSS signal source simulates and simultaneously transmits satellite signals of 4 or more GNSS navigation satellites; and S2: The GNSS signal receiver receives satellite signals transmitted by at least one GNSS signal source, and determines its own position according to the satellite signals; the navigation message of each satellite signal simulated and transmitted by each GNSS signal source is embedded with The geographic location of the GNSS signal source itself, when the GNSS signal receiver receives satellite signals transmitted by at least two GNSS signal sources, and the satellite signals transmitted by the GNSS signal sources interfere with each other, then the GNSS signal The receiver determines its position by: According to the geographic location information of the navigation message in each satellite signal, group all the simulated satellites into groups to obtain multiple groups Gj, j is the group number, j=0,1,2,...; The geographic location of each GNSS signal source forms a set P; Calculate the average carrier-to-noise ratio of the satellite signals in each group Gj, and calculate the distance from the GNSS signal receiver to the GNSS signal source corresponding to each group Gj according to the carrier-to-noise ratio to form a set D; and Obtain its own position according to the set P and set D.