A mobile Loran positioning system and its transmission signal modulation method and reception signal analysis method

Abstract

The present invention belongs to the technical field related to communication engineering, and discloses a mobile Loran positioning system and its transmission signal modulation method and reception signal analysis method. The analysis method includes: obtaining the modulated pulse groups transmitted in sequence by three signal transmitting devices received by the receiving port, the three modulated pulse groups carrying the coordinate information of the main station, auxiliary station 1 and auxiliary station 2; obtaining the coordinate information of each signal transmitting device through demodulation and decoding, and restoring each modulated pulse to the reference pulse position, and then accumulating to obtain the accumulated pulse of each signal transmitting device; and calculating the receiving position based on the accumulated pulse. Through the above method, the present invention can obtain the coordinate information of the transmitting station on the one hand, support the mobile deployment of the transmitting station, and by restoring the modulated pulse to the reference pulse position and then accumulating, this method eliminates the influence of the pulse modulation position and can obtain the highest accumulated pulse signal-to-noise ratio, thereby improving positioning accuracy.

Description

Technical Field

[0001] The present invention belongs to the technical field related to communication engineering, and more specifically, relates to a motorized Loran positioning system and a transmission signal modulation method and a reception signal analysis method thereof. Background Art

[0002] The Loran positioning system, with its advantages such as stable ground wave signal phase, strong anti-interference ability, high reliability, wide coverage, and differential enhancement function, can make up for many defects of GNSS and thus enhance the positioning, navigation and timing (PNT) service guarantee capability.

[0003] The basic principle of the existing Loran positioning system is to achieve balanced modulation by using the emission time control method for the 3rd to 8th pulses of each GRI cycle of the ELoran signal, that is, to perform emission punctual, advance, and lag modulation of a single ELoran pulse signal at 0μs and ±1μs, and the sum of the modulation times of the modulated pulses in each pulse group is 0 to achieve balanced modulation.

[0004] However, the current Loran positioning system needs to work in a high signal-to-noise ratio environment. If a mobile transmitting station is used, its signal-to-noise ratio is low, resulting in poor positioning accuracy. Therefore, in order to obtain a high signal-to-noise ratio, it is generally necessary to build a high-power transmitting station with a fixed position. The construction and deployment costs of high-power transmitting stations are high, and once deployed, the position is fixed and cannot be maneuvered. However, some specific environments require mobile deployment. The current Loran positioning method cannot achieve maneuverability, which limits the application scenarios. Summary of the Invention

[0005] In response to the above defects or improvement needs of the prior art, the present invention provides a mobile Loran positioning system and its transmission signal modulation method and reception signal analysis method, the purpose of which is to improve positioning accuracy and achieve mobile deployment.

[0006] To achieve the above object, the present invention provides a received signal analysis method for realizing motorized Loran positioning, which comprises:

[0007] Obtain modulated pulse groups sequentially transmitted by three signal transmitting devices received by the receiving port, where each modulated pulse group contains M modulated pulses, and the M modulated pulses in at least one modulated pulse group are obtained by encoding the signal transmitting device with transmit data carrying coordinate information and then position modulating M reference pulses. The three signal transmitting devices are respectively the main station, auxiliary station 1, and auxiliary station 2, and the three modulated pulse groups carry the coordinate information of the main station, auxiliary station 1, and auxiliary station 2;

[0008] Demodulating and decoding each modulated pulse group to obtain transmission data of each signal transmitting device, recovering coordinate information of each signal transmitting device from the transmission data, and restoring each modulated pulse of each modulated pulse group to a reference pulse position to obtain a restored pulse group of each signal transmitting device;

[0009] Accumulate the last M-1 reduction pulses in the reduction pulse group of each signal emitting device to the first reduction pulse to obtain an accumulated pulse of each signal emitting device;

[0010] Calculate the reception time difference between the accumulated pulses of the main station and the accumulated pulses of slave station 1, calculate the distance difference d1 between the main station and slave station 1 and the receiving end, calculate the reception time difference between the accumulated pulses of the main station and the accumulated pulses of slave station 2, and calculate the distance difference d2 between the main station and slave station 2 and the receiving end;

[0011] The receiving position is calculated based on the distance difference d1, the distance difference d2 and the coordinate information of each signal transmitting device.

[0012] Optionally, calculating the receiving position based on the distance difference d1, the distance difference d2 and the coordinate information of each signal transmitting device includes:

[0013] Using the main station coordinates, the auxiliary station 1 coordinates and the distance difference d1, a first hyperbola is drawn, the absolute value of the distance difference between the main station coordinates and the auxiliary station 1 coordinates being d1;

[0014] Using the main station coordinates, the auxiliary station 2 coordinates and the distance difference d2, a second hyperbola is drawn, the absolute value of the distance difference between the main station coordinates and the auxiliary station 2 coordinates being d2;

[0015] The intersection of the first hyperbola and the second hyperbola is solved, and the coordinates of the intersection are the position of the receiving end.

[0016] The present invention also provides a signal receiving device for realizing motorized Loran positioning, which includes a receiving port, a memory and a processor. The receiving port is used to receive modulated pulse groups transmitted in sequence by three signal transmitting devices. The memory stores a computer program. When the processor executes the computer program, the steps of the received signal analysis method as described above are implemented.

[0017] The present invention also provides a transmission signal modulation method for realizing motorized Loran positioning, which is used to generate a modulated pulse group transmitted to the signal receiving device as described above, and the modulation method includes:

[0018] Encoding the transmission data carrying the coordinate information of the signal transmitting device to obtain a transmission data code;

[0019] The obtained transmission data code is used to perform position modulation on the M reference pulses to obtain M modulated pulses, and the M modulated pulses are a modulated pulse group for transmission.

[0020] Optionally, the transmitted data is encoded by encoding the transmitted data carrying coordinate information using an L-ary polar code.

[0021] Optionally, the reference pulse is position modulated using the transmitted data encoding, including: converting the transmitted data carrying the coordinate information into M L-ary symbols, encoding to obtain M L-ary modulation information, each modulation information having a value of an integer from 0 to L-1, corresponding to L types of modulation intervals, mapping the M L-ary modulation information to corresponding modulation intervals respectively, modulating the M reference pulses so that the position offset of the reference pulse is mapped by the modulation interval, and obtaining M modulated pulses.

[0022] The present invention also provides a signal transmitting device for realizing mobile Loran positioning, which includes a transmitting port, a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the transmitting signal modulation method as described in any one of the above items are implemented, and the transmitting port is used to transmit the obtained modulated pulse group to the signal receiving device as described above.

[0023] The present invention also provides a motorized Loran positioning system, which comprises:

[0024] Three signal transmitting devices, at least one of which is the signal transmitting device described above, the three signal transmitting devices being maneuverably deployed at different locations, namely a main station, auxiliary station 1, and auxiliary station 2, and the three modulated pulse groups transmitted by the three signal transmitting devices collectively carrying coordinate information of the main station, auxiliary station 1, and auxiliary station 2;

[0025] The signal receiving device as described above.

[0026] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the steps of the received signal analysis method described above or the steps of the transmitted signal modulation method described above are implemented.

[0027] The present invention also provides a computer program product, comprising a computer program or instructions, which, when executed by a processor, implement the steps of the received signal analysis method as described above or the steps of the transmitted signal modulation method as described above.

[0028] In general, the above technical solutions conceived by the present invention have the following beneficial effects compared with the prior art:

[0029] In the present invention, the modulated pulses transmitted by the main station, sub-station 1 and sub-station 2 received by the receiving end carry the coordinate information of the transmitting device. Specifically, the coordinate information is carried by position modulating M pulses. After receiving the transmitted signal, the coordinate information of the transmitting device can be obtained by demodulation and decoding, so the mobile deployment of the transmitting device can be realized; in addition to carrying the coordinate information of the transmitting device, the M pulses are also restored to the reference pulse position by the receiving end, and then the M pulses are accumulated. This method eliminates the influence of coding modulation and can obtain the highest accumulated pulse signal-to-noise ratio, thereby improving positioning accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 1 is a pulse modulation position diagram using octal polar code in one embodiment of the present invention;

[0031] Figure 2 Yes Figure 1 A partial enlarged view of the pulse modulation position diagram shown;

[0032] Figure 3 is a schematic diagram of performing position modulation on a reference pulse after mapping modulation information to a modulation interval in one embodiment of the present invention;

[0033] Figure 4 is a flowchart of the steps of a received signal analysis method for realizing motorized Loran positioning in one embodiment of the present invention;

[0034] Figure 5 is a schematic diagram of obtaining accumulated pulses in one embodiment of the present invention;

[0035] Figure 6 is a signal processing flow chart of the main station, auxiliary station 1 and auxiliary station 2 in one embodiment of the present invention;

[0036] Figure 7 is a signal processing flow chart of a signal receiving device in one embodiment of the present invention. DETAILED DESCRIPTION

[0037] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0038] The Loran positioning system includes a signal transmitter and a signal receiver. The present invention improves these two devices to enhance positioning accuracy and enable flexible deployment. The following describes the system and its signal transmitter and receiver.

[0039] Example 1

[0040] The present invention discloses a transmission signal modulation method for realizing motorized Loran positioning, the modulation method comprising:

[0041] S11: Encode the transmission data carrying the coordinate information of the signal transmitter to obtain a transmission data code;

[0042] S12: Perform position modulation on the M reference pulses using the obtained transmission data code to obtain M modulated pulses, where the M modulated pulses constitute a modulated pulse group for transmission.

[0043] Specifically, the transmission data encoding used in S11 is obtained by encoding the transmission data carrying the coordinate information using an L-ary polar code pair. For example, the transmission data carrying the coordinate information is encoded using an octal polar code pair.

[0044] Specifically, in S12, position modulation is performed on the reference pulse using its own transmit data encoding, including: converting the transmit data carrying coordinate information into M L-ary modulation information, where each modulation information value is an integer from 0 to L-1, mapping the M L-ary modulation information to M modulation intervals, and modulating the M reference pulses so that the positions of the reference pulses are offset by the mapped modulation intervals, thereby obtaining M modulated pulses. The reference pulses at the reference pulse positions do not carry any information.

[0045] like Figure 1 FIG. 1 shows a pulse modulation position diagram using an octal polar code in one embodiment. Figure 2 For example Figure 1 The partial enlarged diagram of the pulse modulation position diagram shown in FIG. Figure 3 The figure shows how the position of a reference pulse is modulated after mapping the modulation information to a modulation interval. After the modulation information is mapped, the modulated pulse and the reference pulse are separated by a time interval, called the modulation interval. The modulation interval carries the modulation information, and different modulation intervals correspond to different modulation information.

[0046] The above-mentioned signal transmitting device can be deployed flexibly because it encodes the transmission data carrying the coordinate information of the signal transmitting device, and then uses the transmission data encoding to modulate the reference pulse to obtain a modulated pulse. That is to say, the M modulated pulses carry the coordinate information of the signal transmitting device. After the signal receiving device receives the modulated pulse group, it can obtain the coordinate information carried by the modulated signal through demodulation and decoding. By modulating the coordinate information into the pulse signal, the mobile deployment of the signal transmitting device can be achieved.

[0047] In specific operations, the modulated pulse group transmitted by a signal transmitting device may carry only its own coordinate information, or it may carry the coordinate information of other signal transmitting devices. For example, the data transmitted by the main station does not contain the coordinate information of the main station, the data transmitted by sub-station 1 contains the coordinate information of the main station and sub-station 1, and the data transmitted by sub-station 2 contains the coordinate information of sub-station 2.

[0048] Example 2

[0049] The present invention also discloses a signal transmitting device for realizing motorized Loran positioning, comprising a transmitting port, a memory and a processor. The memory stores a computer program. When the processor executes the computer program, the transmitting signal modulation method as in Example 1 is implemented to obtain a corresponding modulated pulse group. The transmitting port is used to transmit the obtained modulated pulse group to a signal receiving device.

[0050] Specifically, the processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The memory may be used to store computer programs and / or modules. The processor performs various functions of the electronic device by running or executing the computer programs and / or modules stored in the memory and calling the data stored in the memory.

[0051] Example 3

[0052] The present invention also discloses a method for analyzing received signals to realize motorized Loran positioning, such as Figure 4 FIG2 is a flowchart of a method for analyzing received signals for implementing motorized Loran positioning in an embodiment of the present invention, and the steps are described below.

[0053] S21: Obtain the modulated pulse groups sequentially transmitted by the three signal transmitting devices received by the receiving port, each modulated pulse group contains M modulated pulses, and there is at least one modulated pulse group in which the M modulated pulses are obtained by encoding the transmission data carrying coordinate information by the signal transmitting device and then position modulating the M reference pulses. The three signal transmitting devices are the main station, sub-station 1 and sub-station 2 respectively, and the three modulated pulse groups carry the coordinate information of the main station, sub-station 1 and sub-station 2 in total.

[0054] It can be understood that the main station, sub-station 1 and sub-station 2 are all signal transmitting devices introduced in Example 2. The positions of mobile deployment of different stations are different, but the process of encoding the coordinate information and then modulating the reference pulse to obtain the modulated pulse group is the same.

[0055] S22: Demodulate and decode each modulated pulse group respectively to obtain the transmission data of each signal transmitting device, restore the coordinate information of each signal transmitting device from the transmission data, and restore each modulated pulse of each modulated pulse group to the reference pulse position to obtain a restored pulse group of each signal transmitting device.

[0056] Specifically, the receiving port receives a total of three modulated pulse groups, each with M modulated pulses. After demodulation, the received modulated pulse group of the main station, the modulated pulse group of slave station 1, and the modulated pulse group of slave station 2 are decoded (e.g., SCL decoding of the L-ary polarization code). Based on the demodulation and decoding results, the coordinates of the main station, slave station 1, and slave station 2 are restored. The modulation interval of each of the 3M modulated pulses relative to its reference pulse position is obtained. Based on the obtained modulation interval, each of the 3M modulated pulses is restored to its reference pulse position, resulting in three restored pulse groups: the restored pulse group of the main station, the restored pulse group of slave station 1, and the restored pulse group of slave station 2.

[0057] S23: Accumulate the last M-1 reduction pulses in the reduction pulse group of each signal emitting device to the first reduction pulse to obtain an accumulated pulse of each signal emitting device.

[0058] like Figure 5 FIG. 1 is a schematic diagram of obtaining accumulated pulses in an embodiment of the present invention, as shown in FIG. Figure 5 As shown, the last M-1 restored pulses of the master station's restored pulse group are added to the first pulse position of the master station's restored pulse group to obtain the master station's accumulated pulse; the last M-1 restored pulses of slave station 1's restored pulse group are added to the first pulse position of slave station 1's restored pulse group to obtain the slave station 1 accumulated pulse; and the last M-1 restored pulses of slave station 2's restored pulse group are added to the first pulse position of slave station 2's restored pulse group to obtain the slave station 2 accumulated pulse. By using this pulse accumulation method, the signal-to-noise ratio of the received pulses can be improved, thereby improving positioning accuracy.

[0059] S24: Calculate the reception time difference between the accumulated pulses of the main station and the accumulated pulses of the slave station 1, calculate the distance difference d1 between the main station and the slave station 1 and the receiving end, calculate the reception time difference between the accumulated pulses of the main station and the accumulated pulses of the slave station 2, and calculate the distance difference d2 between the main station and the slave station 2 and the receiving end.

[0060] Specifically, compare the accumulated pulses of the main station and the accumulated pulses of slave station 1, and calculate the time interval between them, that is, the time difference, which is recorded as t1. Compare the accumulated pulses of the main station and the accumulated pulses of slave station 2, and calculate the time interval between them, that is, the time difference, which is recorded as t2. Calculate the distance difference between the receiving end and the main station and slave station 1: d1 = t1 × c, where c = 3 × 10 8 , is the speed of light. Calculate the distance difference between the receiving end and the main station and the secondary station 2 d2 = t2 × c, c = 3 × 10 8 , is the speed of light.

[0061] S25: Calculate the receiving position based on the distance difference d1, the distance difference d2 and the coordinate information of each signal transmitting device.

[0062] Specifically, using the coordinates of the main station, the coordinates of secondary station 1, and d1, we can draw hyperbola 1, where the absolute value of the distance difference between the main station coordinates and the coordinates of secondary station 1 on the map is d1. Using the coordinates of the main station, the coordinates of secondary station 2, and d2, we can draw hyperbola 2, where the absolute value of the distance difference between the main station coordinates and the coordinates of secondary station 2 on the map is d2. The intersection of hyperbola 1 and hyperbola 2 is coordinate 3, which is the location of the receiving end.

[0063] Through the above method, the present invention can obtain the coordinate information of the transmitting station and support the mobile deployment of the transmitting station. By restoring the modulated pulse to the reference pulse position and then accumulating it, this method eliminates the influence of coding modulation and can obtain the highest accumulated pulse signal-to-noise ratio, thereby improving positioning accuracy.

[0064] Example 4

[0065] The present invention also discloses a signal receiving device for realizing motorized Loran positioning, comprising a receiving port, a memory and a processor. The receiving port is used to receive modulated pulse groups sequentially transmitted by three signal transmitting devices. The memory stores a computer program. When the processor executes the computer program, the received signal analysis method as described in Example 3 is implemented.

[0066] Specifically, the processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The memory may be used to store computer programs and / or modules. The processor performs various functions of the electronic device by running or executing the computer programs and / or modules stored in the memory and calling the data stored in the memory.

[0067] Example 5

[0068] The present invention also discloses a motorized Loran positioning system, which includes three signal transmitting devices and a signal receiving device;

[0069] At least one of the three signal transmitting devices is the signal transmitting device that transmits the pulse group carrying coordinate information introduced in Example 2. The three signal transmitting devices are deployed in different positions, namely the main station, auxiliary station 1 and auxiliary station 2. The three modulated pulse groups transmitted by the three signal transmitting devices carry the coordinate information of the main station, auxiliary station 1 and auxiliary station 2, as shown in FIG. Figure 6 FIG. 1 is a flow chart showing signal processing of three signal transmitting devices in one embodiment of the present invention.

[0070] The signal receiving device is the signal receiving device described in Example 4, such as Figure 7 FIG. 1 is a flow chart showing signal processing of a signal receiving device according to an embodiment of the present invention.

[0071] Example 6

[0072] The present invention also relates to a computer-readable storage medium having a computer program stored thereon, which implements the steps of the above method when the computer program is executed by a processor.

[0073] Specifically, the memory may include a high-speed random access memory, and may also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage device.

[0074] Example 7

[0075] An embodiment of the present invention provides a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the steps of the method of the above embodiment of the present invention.

[0076] The technical features of the above embodiments can be combined in any manner. To simplify the description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification. It should be noted that the phrases "in one embodiment", "for example", "and another example", etc. of the present invention are intended to illustrate the present invention and are not intended to limit the present invention.

[0077] The above embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, and all such variations and improvements fall within the scope of protection of the present invention.

Claims

1. A method for analyzing received signals for realizing motorized Loran positioning, characterized in that: include: Obtain modulated pulse groups sequentially transmitted by three signal transmitting devices received by the receiving port, where each modulated pulse group contains M modulated pulses, and the M modulated pulses in at least one modulated pulse group are obtained by encoding the signal transmitting device with transmit data carrying coordinate information and then position modulating M reference pulses. The three signal transmitting devices are respectively the main station, auxiliary station 1, and auxiliary station 2, and the three modulated pulse groups carry the coordinate information of the main station, auxiliary station 1, and auxiliary station 2; Demodulating and decoding each modulated pulse group to obtain transmission data of each signal transmitting device, recovering coordinate information of each signal transmitting device from the transmission data, and restoring each modulated pulse of each modulated pulse group to a reference pulse position to obtain a restored pulse group of each signal transmitting device; Accumulate the last M-1 reduction pulses in the reduction pulse group of each signal emitting device to the first reduction pulse to obtain an accumulated pulse of each signal emitting device; Calculate the reception time difference between the accumulated pulses of the main station and the accumulated pulses of slave station 1, calculate the distance difference d1 between the main station and slave station 1 and the receiving end, calculate the reception time difference between the accumulated pulses of the main station and the accumulated pulses of slave station 2, and calculate the distance difference d2 between the main station and slave station 2 and the receiving end; The receiving position is calculated based on the distance difference d1, the distance difference d2 and the coordinate information of each signal transmitting device.

2. The received signal analysis method according to claim 1, wherein: Calculating the receiving position based on the distance difference d1, the distance difference d2 and the coordinate information of each signal transmitting device includes: Using the main station coordinates, the auxiliary station 1 coordinates and the distance difference d1, a first hyperbola is drawn, the absolute value of the distance difference between the main station coordinates and the auxiliary station 1 coordinates being d1; Using the main station coordinates, the auxiliary station 2 coordinates and the distance difference d2, a second hyperbola is drawn, the absolute value of the distance difference between the main station coordinates and the auxiliary station 2 coordinates being d2; The intersection of the first hyperbola and the second hyperbola is solved, and the coordinates of the intersection are the position of the receiving end.

3. A signal receiving device for realizing motorized Loran positioning, characterized in that: It includes a receiving port, a memory and a processor, the receiving port is used to receive modulated pulse groups transmitted in sequence by three signal transmitting devices, the memory stores a computer program, and the processor implements the steps of the received signal analysis method as claimed in claim 1 or 2 when executing the computer program.

4. A transmission signal modulation method for realizing motorized Loran positioning, characterized in that: For generating a modulated pulse group transmitted to the signal receiving device according to claim 3, the modulation method comprises: Encoding the transmission data carrying the coordinate information of the signal transmitting device to obtain a transmission data code; The obtained transmission data code is used to perform position modulation on the M reference pulses to obtain M modulated pulses, and the M modulated pulses are a modulated pulse group for transmission.

5. The transmission signal modulation method according to claim 4, wherein: The transmission data code is obtained by encoding the transmission data carrying coordinate information using an L-ary polar code.

6. The transmission signal modulation method according to claim 5, wherein: The method uses transmission data encoding to perform position modulation on a reference pulse, including: converting transmission data carrying coordinate information into M L-ary symbols, obtaining M L-ary modulation information after encoding, wherein each modulation information has a value of an integer from 0 to L-1 and corresponds to L modulation intervals, mapping the M L-ary modulation information to corresponding modulation intervals respectively, and modulating M reference pulses so that the position of the reference pulse is offset by the mapped modulation interval, thereby obtaining M modulated pulses.

7. A signal transmitting device for realizing motorized Loran positioning, characterized in that: The device comprises a transmitting port, a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the transmitting signal modulation method according to any one of claims 4 to 6 are implemented, and the transmitting port is used to transmit the obtained modulated pulse group to the signal receiving device according to claim 3.

8. A motorized Loran positioning system, characterized in that: include: Three signal transmitting devices, at least one of which is the signal transmitting device according to claim 7, the three signal transmitting devices being flexibly deployed at different locations, namely a main station, auxiliary station 1, and auxiliary station 2, and the three modulated pulse groups transmitted by the three signal transmitting devices collectively carry the coordinate information of the main station, auxiliary station 1, and auxiliary station 2; The signal receiving device according to claim 3.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the received signal analysis method according to claim 1 or 2 or the steps of the transmitted signal modulation method according to any one of claims 4 to 6 are implemented.

10. A computer program product comprising a computer program or instructions, characterized in that When the computer program or instruction is executed by a processor, the steps of the received signal analysis method according to claim 1 or 2 or the steps of the transmitted signal modulation method according to any one of claims 4 to 6 are implemented.

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