阅读说明：本技术 一种卫星定位方法及设备 (Satellite positioning method and device ) 是由 许瑞杰 柏如龙 信侃 霍立寰 于 2020-11-30 设计创作，主要内容包括：本发明实施例提供一种卫星定位方法及设备,该方法通过第一卫星在第一预设时间发射的第一下行信号和第二卫星在第一预设时间发射的第二下行信号确定第一时差,以及第一卫星在第二预设时间发射第三下行信号和第二卫星在第二预设时间发射的第四下行信号确定第二时差,再通过第一时差和第二时差确定目标信号源的位置,不需要测量频差参数,且只需要两颗卫星即可实现目标信号源的精确位置,从而能够在卫星数量受限的情况下,使用双星实现较高的定位精度。(The embodiment of the invention provides a satellite positioning method and equipment, the method determines a first time difference through a first downlink signal transmitted by a first satellite at a first preset time and a second downlink signal transmitted by a second satellite at the first preset time, determines a second time difference through a third downlink signal transmitted by the first satellite at a second preset time and a fourth downlink signal transmitted by the second satellite at the second preset time, and determines the position of a target signal source through the first time difference and the second time difference.)

1. A method of satellite positioning, comprising:

acquiring a first downlink signal transmitted by a first satellite and received by a receiver at a first preset time, and a second downlink signal transmitted by a second satellite and received by the receiver, wherein the first downlink signal is acquired by the first satellite according to a first uplink signal transmitted by a target signal source, and the second downlink signal is acquired by the second satellite according to the first uplink signal;

acquiring a third downlink signal transmitted by the first satellite and received by the receiver at a second preset time, and a fourth downlink signal transmitted by the second satellite and received by the receiver, wherein the third downlink signal is acquired by the first satellite according to a second uplink signal transmitted by the target signal source, and the fourth downlink signal is acquired by the second satellite according to the second uplink signal;

determining a first time difference according to the first downlink signal and the second downlink signal;

determining a second time difference according to the third downlink signal and the fourth downlink signal;

and determining the position of the target signal source according to the first time difference and the second time difference.

2. The method of claim 1, wherein determining the location of the target signal source based on the first time difference and the second time difference comprises:

determining a location (x, y, z) of the target signal source according to the following expression:

wherein (x)_s1，y_s1，z_s1) (x) coordinates of the first satellite at the first time_s2，y_s2，z_s2) Is a coordinate of the second satellite at the first time, (x'_s1，y′_s1，z′_s1) Is a coordinate of the first satellite at the second time, (x'_s2，y′_s2，z′_s2) Is the coordinate of the second satellite at the second time, Δ t₁Is a first time difference, Δ t₂For a second time difference,. DELTA.l, is the distance between the first satellite and the receiver and between the second satellite and the receiver at the first timeDistance difference, Δ l', is a difference between a distance from the first satellite to the receiver and a distance from the second satellite to the receiver at the second time, a is a length of a major axis of the earth, and b is a length of a minor axis of the earth.

3. The method according to claim 1, characterized in that the time interval between said first preset time and said second preset time is greater than or equal to 1 hour.

4. A satellite positioning apparatus, comprising: a receiver, at least one processor, and a memory;

the receiver is used for receiving a first downlink signal transmitted by a first satellite, a second downlink signal transmitted by a second satellite, a third downlink signal transmitted by the first satellite and a fourth downlink signal transmitted by the second satellite;

the memory stores computer-executable instructions;

the at least one processor executing the computer-executable instructions stored by the memory causes the at least one processor to perform the satellite positioning method of any of claims 1 to 3.

5. A computer-readable storage medium having stored thereon computer-executable instructions which, when executed by a processor, implement the satellite positioning method of any one of claims 1 to 3.

Technical Field

The embodiment of the invention relates to the technical field of satellite positioning, in particular to a satellite positioning method and equipment.

Background

Satellite positioning is a technology for positioning a target signal source by using a satellite. In the prior art, the two-satellite time difference and frequency difference combined positioning and the three-satellite time difference positioning are common positioning technologies.

The precision of the frequency difference parameter is required to be higher in the two-satellite time difference and frequency difference combined positioning, for example, if the positioning precision is required to be less than 100km, the precision of the frequency difference parameter needs to reach 10mHz, however, the precision of the frequency difference parameter is difficult to reach the requirement due to the frequency difference caused by local oscillator drift of a satellite transponder and the difference of channels of a signal receiving device, so that the positioning precision of the two-satellite time difference and frequency difference combined positioning system is lower.

Although the frequency difference parameters do not need to be measured in the three-satellite time difference positioning, the target signal source cannot be positioned under the condition that the number of satellites is limited due to the fact that the number of the required satellites is large.

Disclosure of Invention

The embodiment of the invention provides a satellite positioning method and equipment, which can realize higher positioning precision by using double satellites under the condition that the number of satellites is limited.

In a first aspect, an embodiment of the present invention provides a satellite positioning method, including: acquiring a first downlink signal transmitted by a first satellite and received by a receiver at a first preset time, and a second downlink signal transmitted by a second satellite and received by the receiver, wherein the first downlink signal is acquired by the first satellite according to a first uplink signal transmitted by a target signal source, and the second downlink signal is acquired by the second satellite according to the first uplink signal;

acquiring a third downlink signal transmitted by the first satellite and received by the receiver at a second preset time, and a fourth downlink signal transmitted by the second satellite and received by the receiver, wherein the third downlink signal is acquired by the first satellite according to a second uplink signal transmitted by the target signal source, and the fourth downlink signal is acquired by the second satellite according to the second uplink signal;

determining a first time difference according to the first downlink signal and the second downlink signal;

determining a second time difference according to the third downlink signal and the fourth downlink signal;

and determining the position of the target signal source according to the first time difference and the second time difference.

In a possible implementation manner, the determining the location of the target signal source according to the first time difference and the second time difference includes:

determining a location (x, y, z) of the target signal source according to the following expression:

wherein (x)_s1，y_s1，z_s1) (x) coordinates of the first satellite at the first time_s2，y_s2，z_s2) Is a coordinate of the second satellite at the first time, (x'_s1，y′_s1，z′_s1) Is a coordinate of the first satellite at the second time, (x'_s2，y′_s2，z′_s2) Is the coordinate of the second satellite at the second time, Δ t₁Is a first time difference, Δ t₂And for a second time difference, Δ l is a difference between a distance from the first satellite to the receiver and a distance from the second satellite to the receiver at the first time, Δ l ' is a difference between a distance from the first satellite to the receiver and a distance from the second satellite to the receiver at the second time, a is a length of a half of the earth's major axis, and b is a length of a half of the earth's minor axis.

In a possible implementation manner, a time interval between the first preset time and the second preset time is greater than or equal to 1 hour.

In a second aspect, the present invention provides a satellite positioning apparatus comprising: a receiver, at least one processor, and a memory;

the receiver is used for receiving a first downlink signal transmitted by a first satellite, a second downlink signal transmitted by a second satellite, a third downlink signal transmitted by the first satellite and a fourth downlink signal transmitted by the second satellite;

the memory stores computer-executable instructions;

the at least one processor executes computer-executable instructions stored by the memory to cause the at least one processor to perform a method for satellite positioning according to the first aspect of the present invention and any one of the possible implementations of the first aspect.

In a third aspect, the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer-executable instructions, and when a processor executes the computer-executable instructions, the method for positioning a satellite according to the first aspect and any possible implementation manner of the first aspect of the present invention is implemented.

In the method, a first time difference is determined by a first downlink signal transmitted by a first satellite at a first preset time and a second downlink signal transmitted by a second satellite at the first preset time, a second time difference is determined by a third downlink signal transmitted by the first satellite at a second preset time and a fourth downlink signal transmitted by the second satellite at the second preset time, and then the position of a target signal source is determined by the first time difference and the second time difference.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic flowchart of a satellite positioning method according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a satellite positioning apparatus according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

When a target signal source is positioned by the double-satellite time difference and frequency difference combined positioning technology, the requirements on the precision of time difference parameters and the precision of frequency difference parameters are high, for example, if the positioning precision is required to be less than 100km, the precision of the time difference parameters needs to reach the microsecond order, and the precision of the frequency difference parameters needs to reach 10 mHz. In practical application, the time difference parameter accuracy easily meets the requirement, however, the frequency difference parameter accuracy is difficult to meet the requirement due to the frequency difference caused by local oscillator drift of the satellite transponder and the difference of the channels of the signal receiving equipment, so that the positioning accuracy of the double-satellite time difference and frequency difference combined positioning system is low. Although the frequency difference parameters do not need to be measured in the three-satellite time difference positioning, the target signal source cannot be positioned under the condition that the number of satellites is limited due to the fact that the number of the required satellites is large.

Based on this, the embodiments of the present invention provide a satellite positioning method and apparatus, which only need to measure a time difference parameter, and only need two satellites to achieve accurate positioning of a target signal source, and can achieve higher positioning accuracy by using two satellites under the condition that the number of satellites is limited.

Fig. 1 is a schematic flowchart of a satellite positioning method according to an embodiment of the present invention, and as shown in fig. 1, the method according to the embodiment of the present invention includes the following steps:

step S101, a first downlink signal transmitted by a first satellite and received by a receiver at a first preset time and a second downlink signal transmitted by a second satellite and received by the receiver are obtained, wherein the first downlink signal is obtained by the first satellite according to a first uplink signal transmitted by a target signal source, and the second downlink signal is obtained by the second satellite according to the first uplink signal.

In an embodiment of the invention, the target signal source transmits a first uplink signal, which is received and retransmitted by the first satellite to generate a first downlink signal, and is received and retransmitted by the second satellite to generate a second downlink signal, and the first downlink signal and the second downlink signal can be received by the receiver.

The acquisition receiver receives a first downlink signal and a second downlink signal at a first preset time. The first preset time is a relatively short period of time during which the positions of the first satellite and the second satellite can be assumed to be fixed. The duration of the first preset time may be set empirically by a technician, for example, the first time is 1 millisecond.

Step S102, obtaining a third downlink signal transmitted by the first satellite and received by the receiver at a second preset time, and a fourth downlink signal transmitted by the second satellite and received by the receiver, where the third downlink signal is obtained by the first satellite according to a second uplink signal transmitted by the target signal source, and the fourth downlink signal is obtained by the second satellite according to the second uplink signal.

In the embodiment of the invention, the time interval between the first preset time and the second preset time is longer, so that the positions of the first satellite and the second satellite at the second preset time are changed greatly compared with the positions at the first preset time. In a preferred implementation, the time interval between the first preset time and the second preset time is greater than or equal to 1 hour. For example, a first downlink signal transmitted by a first satellite received by the receiver from 10 am to 1 am and a second downlink signal transmitted by a second satellite received by the receiver is acquired, a third downlink signal transmitted by the first satellite received by the receiver from 12 am to 12 am and a fourth downlink signal transmitted by the second satellite received by the receiver is acquired.

The second predetermined time is a relatively short period of time during which the positions of the first satellite and the second satellite can be assumed to be fixed. The duration of the second preset time may be set empirically by a skilled person, for example, the second time is 2 milliseconds. The first preset time and the second preset time may be the same or different, and the embodiment of the present invention is not limited specifically.

Step S103, determining a first time difference according to the first downlink signal and the second downlink signal.

Step S104, determining a second time difference according to the third downlink signal and the fourth downlink signal.

The first time difference is determined according to the first downlink signal and the second downlink signal by a correlation detection method, and the second time difference is determined according to the third downlink signal and the fourth downlink signal.

And step S105, determining the position of the target signal source according to the first time difference and the second time difference.

In the embodiment of the invention, a first trajectory formed by the target signal source and the earth surface can be determined according to the first time difference, a second trajectory formed by the target signal source and the earth surface can be determined according to the second time difference, and the intersection point of the intersection of the first trajectory and the second trajectory is the position of the target signal source.

According to the embodiment of the invention, the first time difference is determined through the first downlink signal transmitted by the first satellite at the first preset time and the second downlink signal transmitted by the second satellite at the first preset time, the second time difference is determined through the third downlink signal transmitted by the first satellite at the second preset time and the fourth downlink signal transmitted by the second satellite at the second preset time, and then the position of the target signal source is determined through the first time difference and the second time difference.

As an embodiment of the present invention, one possible implementation manner of step S105 is: determining the location of the target signal source according to the following expression:

wherein (x)_s1，y_s1，z_s1) (x) coordinates of the first satellite at the first time_s2，y_s2，z_s2) Is a coordinate of the second satellite at the first time, (x'_s1，y′_s1，z′_s1) Is a coordinate of the first satellite at the second time, (x'_s2，y′_s2，z′_s2) Is the coordinate of the second satellite at the second time, Δ t₁Is a first time difference, Δ t₂For a second time difference,. DELTA.l is a difference between a distance from the first satellite to the receiver and a distance from the second satellite to the receiver at the first time,. DELTA.l 'is a difference between a distance from the first satellite to the receiver and a distance from the second satellite to the receiver at the second time, and a is half the earth's lengthThe axial length b is the minor semi-axis length of the earth.

In an embodiment of the invention, the coordinate position (x) of the receiver is known₀，y₀，z₀) Δ l and Δ l' are determined according to the following expressions:

fig. 2 is a schematic structural diagram of a satellite positioning apparatus according to an embodiment of the present invention, and as shown in fig. 2, a satellite positioning apparatus 20 according to an embodiment of the present invention includes: a receiver 201, at least one processor 202, and a memory 203. The satellite positioning device 20 further comprises a communication component 204. Wherein the receiver 201, the at least one processor 202 and the memory 203 are connected by a bus 205.

In a specific implementation process, the receiver 201 is configured to receive a first downlink signal transmitted by a first satellite, a second downlink signal transmitted by a second satellite, a third downlink signal transmitted by the first satellite, and a fourth downlink signal transmitted by the second satellite. The memory 203 stores computer-executable instructions and stores a first downlink signal, a second downlink signal, and a third downlink signal and a fourth downlink signal received by the receiver 201 at a first time.

The at least one processor 202 executes the computer-executable instructions stored by the memory 203 to cause the at least one processor 202 to perform the satellite positioning method as performed by the satellite positioning apparatus 20 above.

For a specific implementation process of the processor 202, reference may be made to the above method embodiments, which implement similar principles and technical effects, and this embodiment is not described herein again.

In the embodiment shown in fig. 2, it should be understood that the Processor may be a Central Processing Unit (CPU), other general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of a method disclosed in connection with the present invention may be embodied directly in a hardware processor, or in a combination of the hardware and software modules within the processor.

The memory may comprise high speed RAM memory and may also include non-volatile storage NVM, such as at least one disk memory.

The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended ISA (EISA) bus, or the like. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, the buses in the figures of the present application are not limited to only one bus or one type of bus.

The present application further provides a computer-readable storage medium, in which computer-executable instructions are stored, and when executed by a processor, the computer-readable storage medium implements the satellite positioning method performed by the above satellite positioning apparatus.

The computer-readable storage medium may be implemented by any type of volatile or non-volatile memory device or combination thereof, such as Static Random Access Memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic or optical disk. Readable storage media can be any available media that can be accessed by a general purpose or special purpose computer.

An exemplary readable storage medium is coupled to the processor such the processor can read information from, and write information to, the readable storage medium. Of course, the readable storage medium may also be an integral part of the processor. The processor and the readable storage medium may reside in an Application Specific Integrated Circuits (ASIC). Of course, the processor and the readable storage medium may also reside as discrete components in the apparatus.

Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.