CN111458729B - Satellite positioning method, device, electronic equipment and storage medium - Google Patents
Satellite positioning method, device, electronic equipment and storage medium Download PDFInfo
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- CN111458729B CN111458729B CN202010298127.1A CN202010298127A CN111458729B CN 111458729 B CN111458729 B CN 111458729B CN 202010298127 A CN202010298127 A CN 202010298127A CN 111458729 B CN111458729 B CN 111458729B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
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Abstract
The embodiment of the application provides a satellite positioning method, a satellite positioning device, electronic equipment and a storage medium, all available satellites at present are screened according to a preset initial cut-off angle and the elevation angles of all the available satellites to obtain a first screening result, the initial cut-off angle is adjusted according to the first screening result, all the available satellites at present are screened according to the adjusted cut-off angle to obtain a second screening result, positioning calculation is carried out according to the second screening result, the situation that the positioning accuracy is poor due to the fact that the cut-off angle is too low and large atmospheric error delay and multipath effects are introduced can be avoided, the situation that the positioning accuracy is poor or even cannot be positioned due to the fact that the number of the available satellites is small due to the fact that the cut-off angle is too high can be avoided, and the positioning accuracy is improved.
Description
Technical Field
The present invention relates to satellite positioning, and more particularly, to a satellite positioning method, an apparatus, an electronic device, and a storage medium.
Background
Global Navigation Satellite System (GNSS) can provide positioning, Navigation and time service information quickly, accurately and all-weather, and has been widely used in recent years.
The low elevation angle satellite has large atmospheric delay error and is more prone to multipath effect, so that the positioning error is greatly offset. In the existing GNSS positioning algorithm, a fixed cut-off angle (generally about 10 °) is generally set to ensure that satellites with an elevation angle below the set fixed cut-off angle do not participate in positioning calculation, thereby ensuring that positioning accuracy is not affected by low-elevation satellites with poor pseudo-range observation values.
However, when the method is used for positioning calculation, a part of satellites still have large atmospheric delay errors and multipath effects, so that the final GNSS positioning accuracy is poor.
Disclosure of Invention
The embodiment of the application provides a satellite positioning method, a satellite positioning device, electronic equipment and a storage medium, and can realize satellite positioning precision.
A satellite positioning method, comprising:
screening all available satellites at present according to a preset initial cut-off angle and the elevation angle of each available satellite to obtain a first screening result; the first screening result comprises the number of available satellites that pass the screening;
adjusting the initial cut-off angle according to the first screening result, and screening all the current available satellites according to the adjusted cut-off angle to obtain a second screening result;
and positioning calculation is carried out according to the second screening result.
In one embodiment, the adjusting the initial cut-off angle according to the first screening result, and screening all currently available satellites according to the adjusted cut-off angle to obtain a second screening result includes:
if the first screening result is that the number of the available satellites passing the screening is larger than a preset number threshold, increasing the initial cut-off angle by a preset first adjusting value to obtain a first cut-off angle;
and screening all the current available satellites according to the first cutoff angle to obtain a second screening result.
In one embodiment, the screening all currently available satellites according to the first cutoff angle to obtain a second screening result includes:
acquiring the number of target available satellites from all the current available satellites according to the first cutoff angle; the elevation angle of the target available satellite is greater than the first cutoff angle;
if the number of the target available satellites is larger than the preset number threshold, increasing the first cutoff angle by a preset second adjustment value to obtain an updated first cutoff angle, returning to execute the step of obtaining the number of the target available satellites from all the current available satellites according to the first cutoff angle, and decreasing the last updated first cutoff angle by the second adjustment value until the number of the target available satellites is smaller than or equal to the preset number threshold to obtain a second cutoff angle;
screening all the current available satellites according to the second cut-off angle to obtain a second screening result; the second screening result includes data for available satellites in elevation greater than the second cut-off angle.
In one embodiment, the increasing the first cut-off angle by a preset second adjustment value to obtain an updated first cut-off angle includes:
and if the first cut-off angle is smaller than the preset cut-off angle upper limit value, increasing the first cut-off angle by a preset second adjustment value to obtain an updated first cut-off angle.
In one embodiment, the decreasing the last updated first cut-off angle by the second adjustment value to obtain a second cut-off angle includes:
and if the last updated first cut-off angle is larger than the initial cut-off angle, reducing the last updated first cut-off angle by the second adjusting value to obtain a second cut-off angle.
In one embodiment, the method further comprises:
if the number of the target available satellites is smaller than or equal to the preset number threshold, reducing the first cut-off angle by the first adjusting value to obtain a third cut-off angle;
screening all the current available satellites according to the third cut-off angle to obtain a second screening result; the second screening result includes data for available satellites in elevation greater than the third cutoff angle.
In one embodiment, the method further comprises:
and if the first screening result is that the number of the screened available satellites is smaller than or equal to the preset number threshold, performing positioning calculation according to the data of the screened available satellites.
In one embodiment, the screening all available satellites currently according to a preset initial cut-off angle and an elevation angle of each available satellite to obtain a first screening result includes:
and comparing the initial cut-off angle with the elevation angle of each available satellite, and determining the number of available satellites with the elevation angles larger than the initial cut-off angle as the first screening result.
In one embodiment, the second filtering result includes data of available satellites having elevation angles greater than the adjusted cut-off angle; the positioning calculation according to the second screening result includes:
and performing positioning calculation according to the data of the available satellite with the elevation angle larger than the adjusted cut-off angle by adopting a least square method or a Kalman filtering algorithm.
A satellite positioning device, comprising:
the first screening module is used for screening all available satellites at present according to a preset initial cut-off angle and the elevation angles of all available satellites to obtain a first screening result; the first screening result comprises the number of available satellites that pass the screening;
the second screening module is used for adjusting the initial cut-off angle according to the first screening result and screening all the current available satellites according to the adjusted cut-off angle to obtain a second screening result;
and the positioning module is used for positioning and resolving according to the second screening result.
An electronic device comprising a memory and a processor, the memory having stored thereon a computer program that, when executed by the processor, causes the processor to perform the steps of the satellite positioning method of any of the above.
A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the method of any of the above.
The satellite positioning method, the satellite positioning device, the electronic equipment and the storage medium provided by the embodiment of the application screen all available satellites currently according to the preset initial cut-off angle and the elevation angle of each available satellite to obtain a first screening result, adjust the initial cut-off angle according to the first screening result, screen all available satellites currently according to the adjusted cut-off angle to obtain a second screening result, perform positioning calculation according to the second screening result, screen the available satellites according to the initial cut-off angle, adaptively adjust the cut-off angle according to the number of the available satellites passing the screening, and screen the available satellites again according to the adjusted cut-off angle, so that the cut-off angle is more matched with the current actual positioning environment, and not only can the problem that the cut-off angle is too low and large atmospheric error delay and multipath effect are caused to cause poor positioning accuracy be avoided, the situation that the positioning accuracy is poor or even the positioning cannot be carried out due to the fact that the number of available satellites is small due to the fact that the cutoff angle is too high can be avoided, and the positioning accuracy is improved.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a diagram illustrating an exemplary environment in which a satellite positioning method may be implemented;
FIG. 2 is a flowchart of a method for positioning a satellite according to an embodiment;
FIG. 3 is a flow chart of a method for satellite positioning according to one embodiment;
FIG. 4 is a flow chart of a method for satellite positioning according to one embodiment;
fig. 5 is a flowchart of a satellite positioning method according to an embodiment of the present application;
FIG. 6 is a block diagram of a satellite positioning device according to an embodiment;
FIG. 7 is a block diagram of a satellite positioning device according to an embodiment;
fig. 8 is a schematic diagram of an internal structure of an electronic device in one embodiment.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
It will be understood that, as used herein, the terms "first," "second," and the like may be used herein to describe various elements, but these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first client may be referred to as a second client, and similarly, a second client may be referred to as a first client, without departing from the scope of the present application. Both the first client and the second client are clients, but they are not the same client.
Fig. 1 is a schematic diagram of an application environment of a satellite positioning method according to an embodiment. The Satellite positioning method can be applied to a Global Navigation Satellite System (GNSS), as shown in fig. 1, where the application environment includes a receiver 1 and a plurality of satellites 2. The receiver 1 may be a GNSS receiver or a Global Positioning System (GPS) receiver, and the receiver 1 may receive signals of a plurality of navigation satellites, which may be the same type of satellite or different types of satellites. The receiver screens all available satellites at present according to a preset initial cut-off angle and the elevation angle of each available satellite, adjusts the initial cut-off angle according to the number of the available satellites passing the screening, screens all available satellites at present according to the adjusted cut-off angle, performs positioning calculation according to the result after the screening, and can automatically adapt and adjust the cut-off angle to further improve the positioning precision of the GNSS.
Fig. 2 is a flowchart of a satellite positioning method according to an embodiment. The satellite positioning method in this embodiment is described by taking the receiver operating in fig. 1 as an example. As shown in fig. 2, the method may include the steps of:
s201, screening all available satellites at present according to a preset initial cut-off angle and the elevation angle of each available satellite to obtain a first screening result; the first screening result includes the number of available satellites that pass the screening.
The initial cut-off angle may be set according to actual conditions, for example, the initial cut-off angle may be 10 ° or 15 °, for example, for a scene with a wider environment, the initial cut-off angle may be set to be lower, so that the receiver can receive more satellites, and for a scene with more obstacles, the cut-off angle may be set to be higher, so as to reduce the influence of the low-elevation satellite on positioning calculation, which is not limited in the embodiment of the present application.
In this embodiment, after acquiring the elevation angles of the available satellites, the receiver screens the available satellites according to the initial cut-off angle, for example, the available satellites with the elevation angles larger than the initial cut-off angle may be used as the satellites that have passed the screening. The first screening result may include the number of available satellites that have passed the screening, and may also include an identification of the available satellites that have passed the screening, data of the available satellites that have passed the screening, and the like, which is not limited in the embodiment of the present application.
S202, adjusting the initial cut-off angle according to the first screening result, and screening all available satellites at present according to the adjusted cut-off angle to obtain a second screening result.
In this embodiment, the initial cut-off angle may be adjusted according to the first screening result, for example, when the number of available satellites that pass the screening in the first screening result is large, the cut-off angle may be further increased, and all currently available satellites are screened according to the increased cut-off angle; or, when the number of available satellites passing the screening in the first screening result is too small to be positioned and solved, the cut-off angle can be adjusted to be small appropriately, and all available satellites at present can be screened according to the cut-off angle after being adjusted to be small.
Moreover, when the number of the screened available satellites still does not meet the requirement after the initial cut-off angle is adjusted for the first time, the cut-off angle can be adjusted for the second time until the number of the screened available satellites meets the requirement, for example, when the number of the screened available satellites is still more after the initial cut-off angle is increased, the cut-off angle can be increased again to screen the available satellites; or when the number of the screened available satellites is still too small after the initial cut-off angle is adjusted to be small, the cut-off angle can be reduced again to screen the available satellites.
Optionally, the second filtering result may include the number of available satellites that are filtered according to the adjusted cut-off angle, and may further include an identifier, data, and the like of the available satellites that are filtered according to the adjusted cut-off angle, which is not limited in the embodiment of the present application.
It should be noted that the cutoff angle may be adaptively adjusted according to the number of the available satellites after each screening, and specifically, the cutoff angle needs to be adjusted several times, the cutoff angle is adjusted to be larger or smaller, and the step length of the adjustment may be set according to the actual situation, which is not limited in the embodiment of the present application.
And S203, positioning calculation is carried out according to the second screening result.
In this embodiment of the application, positioning calculation may be performed according to the second screening result, for example, when the second screening result includes an identifier of an available satellite that is screened according to the adjusted cut-off angle, data of the available satellite corresponding to the identifier is obtained, and positioning calculation is performed according to the data of the available satellite; or when the second screening result comprises the available satellites screened according to the adjusted cut-off angle, directly performing positioning calculation on the data of the available satellites; alternatively, the embodiment of the present application is not limited to this, and the like, and the positioning solution is performed by selecting data of a part of available satellites from the available satellites screened according to the adjusted cutoff angle.
In this embodiment, after the available satellites that need to participate in positioning are selected according to the above scheme, positioning calculation can be performed. Taking the GNSS receiver as an example, the GNSS receiver is essentially a range finder, and the GNSS receiver receives signals transmitted by satellites and demodulates to calculate the distances from the satellites to the receiver. However, the distance is not the distance from the real satellite to the GNSS receiver, and includes a large amount of error, so the distance measured by the GNSS receiver is generally referred to as a pseudorange. The pseudorange measured by the GNSS receiver is obtained by calculating the time delay of the satellite signal from the satellite to the GNSS receiver and multiplying the time delay by the signal propagation speed (i.e., the light speed c), and meanwhile, the satellite position is obtained by resolving ephemeris information containing orbit parameters broadcasted by the satellite in real time.
In an ideal situation, GNSS positioning can obtain high-precision positioning, however, the actual situation obviously does not meet the requirement, and a large amount of errors exist in the measurement process, which results in insufficient precision, and here we classify the errors into the following three categories:
1. satellite-side errors, errors caused by insufficient precision of orbit information obtained by calculation of ephemeris information broadcasted in real time, satellite clock deviation introduced into pseudo range, phase center deviation and phase winding of a satellite antenna and the like;
2. in the process of propagation, errors occur, atmospheric refraction can occur in the process of satellite signals reaching a receiver, so that the speed is reduced, the propagation delay is increased, and the pseudo range is larger relative to the real distance, and the errors mainly comprise a convection process refraction error and an ionosphere;
3. receiver end errors, receiver clock bias, multipath effect errors, receiver antenna phase center bias, relativistic effect bias, and the like.
In summary, the following equations can be obtained for each satellite:
P＝R+c(Ts+Tr)+Di+Dt+ε；
wherein, P represents a pseudo-range observed value obtained by measurement, and is known and obtained by measurement of a receiver; r represents the real distance from the satellite to the earth, a linear equation needs to be developed through Taylor series, the satellite coordinates are known and are obtained by calculating satellite orbit parameters broadcasted in real time, the receiver coordinates are unknown and are to be solved, and three unknown numbers are obtained; ts represents the clock error of the satellite, known and obtained by calculating the clock error related information broadcast in real time; tr represents a receiver clock error, unknown, an unknown number to be solved; di represents deviation caused by ionospheric refraction, double-frequency resolution can be achieved, a known number is generally changed by model calculation in a single frequency mode, and for a satellite with a high elevation angle, the smaller the model error is; dt represents the deviation caused by the process refraction, which is generally changed into a known number through model calculation, and for a satellite with a high elevation angle, the smaller the model error is; epsilon represents residual errors including multipath effects (the higher the elevation angle, the smaller the multipath error), measurement value accuracy errors, model residual errors, etc., and is not generally processed.
In summary, at least 15 usable satellites can obtain at least 15 solution equations, and the unknowns to be solved are only 4, that is, the receiver coordinates (x, y, z) and the receiver clock difference (Tr), which increases one inter-system receiver clock difference with the increase of the positioning system, so that the solution requirements can be completely met according to the 15 solution equations, and because the satellites are all high elevation angles, the residual error is smaller, and the solution accuracy is naturally higher. Before solving, the equation is linearized according to Taylor series expansion, and then a positioning optimal solution can be obtained by adopting a least square method or a Kalman filtering method.
The satellite positioning method provided by the embodiment of the application screens all available satellites at present according to a preset initial cut-off angle and elevation angles of all available satellites to obtain a first screening result, adjusts the initial cut-off angle according to the first screening result, screens all available satellites at present according to the adjusted cut-off angle to obtain a second screening result, performs positioning calculation according to the second screening result, screens the available satellites according to the initial cut-off angle, adaptively adjusts the cut-off angle according to the number of the available satellites passing the screening, screens the available satellites again according to the adjusted cut-off angle to enable the cut-off angle to be more matched with the current actual positioning environment, can avoid poor positioning accuracy caused by large atmospheric error delay and multipath effect introduced by the cut-off angle, can also avoid poor positioning accuracy caused by small number of available satellites due to too high cut-off angle and even cannot perform positioning, the positioning accuracy is improved.
Further, on the basis of the embodiment shown in fig. 2, the satellite positioning method further includes: and if the first screening result is that the number of the available satellites passing the screening is smaller than or equal to a preset number threshold, performing positioning calculation according to the data of the available satellites passing the screening.
In this embodiment, if the number of the available satellites screened by the initial cut-off angle is less than or equal to the preset number threshold, positioning calculation is directly performed according to the data of the screened available satellites, the cut-off angle does not need to be adjusted, and positioning efficiency is improved.
Fig. 3 is a flowchart of a satellite positioning method according to an embodiment, which relates to a specific implementation manner of adjusting the initial cut-off angle according to the first screening result and screening all currently available satellites according to the adjusted cut-off angle to obtain the second screening result, as shown in fig. 3, step S202 may include the following steps:
s301, if the first screening result is that the number of the available satellites passing the screening is larger than a preset number threshold, increasing the initial cut-off angle by a preset first adjusting value to obtain a first cut-off angle.
The first adjustment value and the preset number threshold may be set according to actual situations, for example, the first adjustment value may be 3 °, 5 °, 10 °, and the like, and the preset number threshold may be 10, 15, 20, and the like, which is not limited in the embodiment of the present application.
In this embodiment, if the number of available satellites screened according to the initial cut-off angle is smaller than the preset number threshold, the initial cut-off angle is increased by the first adjustment value to obtain the first cut-off angle. For example, the initial cut-off angle is 10 °, the preset quantity threshold is 15, the first adjustment value is 5 °, if the number of available satellites in elevation angle greater than 10 ° is 22, the number of available satellites in screening pass 22 is greater than 15, and the initial cut-off angle of 10 ° is increased to 15 °.
S302, screening all available satellites at present according to the first cutoff angle to obtain a second screening result.
In this embodiment, the receiver performs screening on all currently available satellites according to the first cutoff angle, for example, screening out available satellites with elevation angles larger than the first cutoff angle, and using the number, identification, data, and the like of the screened available satellites as a second screening result.
According to the satellite positioning method provided by the embodiment of the application, if the first screening result is that the number of the available satellites passing the screening is larger than the preset number threshold, the initial cut-off angle is increased by the preset first adjustment value to obtain the first cut-off angle, all the available satellites at present are screened according to the first cut-off angle to obtain the second screening result, when the number of the available satellites screened by using the initial cut-off angle is large, the cut-off angle can be further increased, the available satellites are screened again through the increased cut-off angle, the situation that the positioning accuracy is poor due to the fact that the cut-off angle is too low and large atmospheric error delay and multipath effects are introduced is further avoided, the influence of low elevation angle satellites on positioning calculation is reduced, and the positioning accuracy is improved.
Further, in order to improve the positioning accuracy, the cut-off angle may be adjusted multiple times during the process of screening all currently available satellites according to the first cut-off angle. As shown in fig. 4, step S302 may include the steps of:
s401, acquiring the number of target available satellites from all available satellites at present according to a first cutoff angle; if the number of the target available satellites is greater than the preset number threshold, step S402 is executed, and if the number of the target available satellites is less than or equal to the preset number threshold, step S404 is executed.
Wherein the elevation angle of the target available satellite is greater than the first cutoff angle.
In this embodiment, the first cutoff angle is compared with the elevation angles of the available satellites, the available satellites having the elevation angles larger than the first cutoff angle are determined as target available satellites, and the number of the target available satellites is counted.
S402, increasing the first cut-off angle by a preset second adjustment value to obtain an updated first cut-off angle, returning to execute the step of obtaining the number of target available satellites from all current available satellites according to the first cut-off angle until the number of the target available satellites is smaller than or equal to a preset number threshold, and decreasing the last updated first cut-off angle by the second adjustment value to obtain a second cut-off angle.
The second adjustment value may be the same as the first adjustment value, or may be different from the first adjustment value, and the second adjustment value may be 3 °, 5 °, 10 °, and the like, which is not limited in this embodiment.
In this embodiment, the available satellites are screened according to the first cutoff angle, if the number of the screened target available satellites is greater than the preset number threshold, the cutoff angle is continuously increased, the available satellites are screened according to the increased first cutoff angle, the number of the screened available satellites is compared with the preset number threshold again, if the number of the screened available satellites is less than the preset number threshold, the number of the screened available satellites is used as the number of the target available satellites, and if the number of the screened available satellites is greater than or equal to the preset number threshold, the cutoff angle may be continuously increased until the number of the screened available satellites is less than the preset number threshold.
For example, taking the initial cut-off angle as 10 ° and the preset number threshold as 15, if the number of available satellites with an elevation angle greater than 10 ° is greater than 15, the cut-off angle is increased to 15 °, if the number of available satellites with an elevation angle greater than 15 ° is greater than 15, the cut-off angle is increased to 20 ° for screening, if the number of available satellites with an elevation angle greater than 20 ° is less than or equal to 15, the cut-off angle is decreased to 15 °, and positioning is performed by using data of the available satellites with an elevation angle greater than 15 °.
In addition, in the embodiment of the application, when the number of the screened available satellites is smaller than the preset number threshold, the first cut-off angle updated at the last time can be reduced by the second adjustment value to obtain the second cut-off angle, so that the problem that the positioning accuracy is reduced due to the fact that the number of the screened available satellites is too small due to the fact that the cut-off angle is too large is solved, and it can be ensured that at least the available satellites with the preset number threshold are selected to ensure the positioning accuracy.
Optionally, increasing the first cut-off angle by a preset second adjustment value to obtain an updated first cut-off angle, including: and if the first cut-off angle is smaller than the preset cut-off angle upper limit value, increasing the first cut-off angle by a preset second adjustment value to obtain an updated first cut-off angle.
In this embodiment, the preset upper limit of the cut-off angle may be determined according to an actual positioning environment, for example, the upper limit of the cut-off angle may be 28 °,30 °, 32 °, and the like, and optionally, a lower limit of the cut-off angle may also be set, for example, the lower limit of the cut-off angle may be 10 °, 15 °, and the like, which is not limited in this embodiment.
In this embodiment, if the first cut-off angle is smaller than the preset upper limit of the cut-off angle, the first cut-off angle is increased by the preset second adjustment value to obtain an updated first cut-off angle, so as to ensure that the first cut-off angle is within a certain range, and avoid the problem that the positioning accuracy is reduced because too many usable satellites should be screened because of too large cut-off angle.
Optionally, decreasing the last updated first cut-off angle by the second adjustment value to obtain a second cut-off angle, including: and if the first cutoff angle updated for the last time is larger than the initial cutoff angle, reducing the first cutoff angle updated for the last time by a second adjustment value to obtain a second cutoff angle.
In this embodiment, if the last updated first cut-off angle is greater than the initial cut-off angle, the last updated first cut-off angle is decreased by the second adjustment value to obtain the second cut-off angle, and generally, the initial cut-off angle may be a lower limit value of the cut-off angle.
S403, screening all available satellites at present according to the second cut-off angle to obtain a second screening result; the second screening result includes data for available satellites having elevation angles greater than a second cutoff angle.
In the embodiment, the second cut-off angle is compared with the elevation angles of all available satellites, and the data of the available satellites with the elevation angles larger than the second cut-off angle is subjected to positioning calculation.
S404, reducing the first cut-off angle by a first adjusting value to obtain a third cut-off angle; and screening all available satellites at present according to the third cut-off angle to obtain a second screening result.
Wherein the second screening result includes data of available satellites having elevation angles greater than the third cutoff angle.
In this embodiment, if the number of the target available satellites is less than or equal to the preset number threshold, the first cutoff angle is decreased by the first adjustment value to obtain a third cutoff angle, and all the current available satellites are screened according to the third cutoff angle to obtain a second screening result.
For example, taking the initial cut-off angle as 10 ° and the preset number threshold as 15, if the number of available satellites with an elevation angle greater than 10 ° is greater than 15, the cut-off angle is increased to 15 °, if the number of available satellites with an elevation angle greater than 15 ° is less than or equal to 15, the cut-off angle is decreased to 10 °, and positioning calculation is performed by using data of available satellites with an elevation angle greater than 10 °.
Optionally, the initial cut-off angle, the first cut-off angle, and the second cut-off angle may be within the range [10,30], so as to ensure that at least a preset number of available satellites are selected, for example, at least 15 available satellites are selected for positioning solution.
According to the satellite positioning method provided by the embodiment of the application, the number of target available satellites is obtained from all current available satellites according to the first cutoff angle; if the number of the target available satellites is larger than the preset number threshold, increasing the first cutoff angle by a preset second adjustment value to obtain an updated first cutoff angle, returning to execute the step of obtaining the number of the target available satellites from all the current available satellites according to the first cutoff angle until the number of the target available satellites is smaller than or equal to the preset number threshold, decreasing the first cutoff angle updated at the last time by the second adjustment value to obtain a second cutoff angle, and screening all the current available satellites according to the second cutoff angle to obtain a second screening result; if the number of the target available satellites is smaller than or equal to the preset number threshold, reducing the first cut-off angle by a first adjusting value to obtain a third cut-off angle; and screening all available satellites at present according to the third cut-off angle to obtain a second screening result, and adaptively adjusting the cut-off angle according to the actual positioning environment, so that the number of the screened available satellites can meet the positioning accuracy, and the large atmospheric error delay and multipath effect introduced by the low-elevation satellites can be reduced or even avoided, thereby improving the positioning accuracy.
On the basis of the above embodiments of fig. 2 to 4, step S201 "filters all currently available satellites according to a preset initial cut-off angle and an elevation angle of each available satellite, to obtain a first filtering result," including: and comparing the initial cut-off angle with the elevation angles of all available satellites, and determining the number of the available satellites with the elevation angles larger than the initial cut-off angle as a first screening result.
In this embodiment, an initial cut-off angle may be set according to an empirical value, the initial cut-off angle is compared with the elevation angles of the available satellites, the number of the available satellites with the elevation angles larger than the initial cut-off angle is counted, and it is determined that the cut-off angle needs to be adjusted according to the number of the available satellites with the elevation angles larger than the initial cut-off angle, that is, the cut-off angle is adjusted according to the current actual positioning environment, so as to meet the current positioning environment requirement and improve the positioning accuracy.
Optionally, on the basis of the above-mentioned embodiments of fig. 2 to 4, the second screening result of step S203 ″ includes data of available satellites with elevation angles larger than the adjusted cut-off angle; and performing positioning calculation according to the second screening result, wherein the positioning calculation comprises the following steps: and performing positioning calculation according to the data of the available satellites with the elevation angles larger than the adjusted cut-off angle by adopting a least square method or a Kalman filtering algorithm.
In this embodiment, a least square method may be used to perform positioning calculation according to the data of the available satellite with the elevation angle greater than the adjusted cut-off angle, or a kalman filter algorithm may be used to perform positioning calculation according to the data of the available satellite with the elevation angle greater than the adjusted cut-off angle. Other algorithms can be used for positioning calculation, and those skilled in the art can select a suitable algorithm according to actual scenes and requirements.
Fig. 5 is a flowchart of a satellite positioning method according to an embodiment of the present disclosure, and as shown in the drawing, the method may include the following steps:
and S501, acquiring data of all available satellites.
Wherein the data of the available satellites includes elevation angles of the available satellites.
And S502, setting an initial cut-off angle.
S503, determining the number of available satellites with elevation angles larger than the current cut-off angle, if the number is smaller than or equal to a preset number threshold, executing step S504, and if the number is larger than the preset number threshold, executing step S507.
The current cut-off angle may be an initial cut-off angle or an adjusted cut-off angle.
S504, determine whether the current cut-off angle is the initial cut-off angle, if yes, execute step S509, otherwise execute step S505.
And S505, reducing the current cut-off angle by a preset adjustment value to obtain a new current cut-off angle.
S506, the number of available satellites with elevation angles larger than the new cut-off angle is acquired, and step S509 is performed.
And S507, judging whether the current cut-off angle is larger than a preset cut-off angle upper limit value or not, if the cut-off angle is smaller than the cut-off angle upper limit value, executing S508, and if the cut-off angle is larger than or equal to the cut-off angle upper limit value, executing S509.
And S508, increasing the cut-off angle by a preset adjusting value, and returning to the step S503.
And S509, performing positioning calculation according to the data of the available satellite screened by the current cut-off angle by adopting a least square method or a Kalman filtering method.
And S5010, outputting a calculation result, and returning to the step S501.
According to the satellite positioning method provided by the embodiment of the application, the available satellites are screened according to the cut-off angles, the cut-off angles are adjusted in a self-adaptive mode according to the number of the screened available satellites, the adjusted cut-off angles meet the requirements of an actual positioning environment, the problem that in the prior art, the positioning accuracy is poor due to the fact that the cut-off angles are too low and large atmospheric error delay and multipath effects are introduced can be solved, and the situation that the positioning accuracy is poor or even the positioning cannot be achieved due to the fact that the number of the available satellites is small due to the fact that the cut-off angles are too high can be avoided.
It should be understood that although the various steps in the flowcharts of fig. 2-5 are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Moreover, at least some of the steps in fig. 2-5 may include multiple sub-steps or multiple stages that are not necessarily performed at the same time, but may be performed at different times, and the order of performance of the sub-steps or stages is not necessarily sequential, but may be performed in turn or alternating with other steps or at least some of the sub-steps or stages of other steps.
Fig. 6 is a block diagram of a satellite positioning apparatus according to an embodiment. As shown in fig. 6, the apparatus includes:
the first screening module 11 is configured to screen all currently available satellites according to a preset initial cut-off angle and elevation angles of the available satellites to obtain a first screening result; the first screening result comprises the number of available satellites that pass the screening;
the second screening module 12 is configured to adjust the initial cut-off angle according to the first screening result, and screen all currently available satellites according to the adjusted cut-off angle to obtain a second screening result;
and the positioning module 13 is used for performing positioning calculation according to the second screening result.
In the satellite positioning device provided by the embodiment of the application, the first screening module 11 screens all available satellites at present according to a preset initial cut-off angle and an elevation angle of each available satellite to obtain a first screening result; the second screening module 12 adjusts the initial cut-off angle according to the first screening result, and screens all currently available satellites according to the adjusted cut-off angle to obtain a second screening result; the positioning module 13 performs positioning calculation according to the second screening result, can screen the available satellites according to the initial cut-off angle, adaptively adjusts the cut-off angle according to the number of the available satellites passing the screening, and screens the available satellites again according to the adjusted cut-off angle, so that the cut-off angle is more matched with the current actual positioning environment, thereby not only preventing poor positioning accuracy caused by large atmospheric error delay and multipath effect due to too low cut-off angle, but also preventing poor positioning accuracy or even incapability of positioning caused by less number of the available satellites due to too high cut-off angle, and improving the positioning accuracy.
In one embodiment, as shown in fig. 7, the second screening module 12 includes:
an obtaining unit 121, configured to increase the initial cut-off angle by a preset first adjustment value to obtain a first cut-off angle if the first screening result indicates that the number of the available satellites that pass the screening is greater than a preset number threshold;
and the screening unit 122 is configured to screen all currently available satellites according to the first cutoff angle to obtain a second screening result.
In one embodiment, the screening unit 122 is configured to obtain the number of target available satellites from all currently available satellites according to the first cutoff angle; the elevation angle of the target available satellite is greater than the first cutoff angle; if the number of the target available satellites is larger than the preset number threshold, increasing the first cutoff angle by a preset second adjustment value to obtain an updated first cutoff angle, returning to execute the step of obtaining the number of the target available satellites from all the current available satellites according to the first cutoff angle, and decreasing the last updated first cutoff angle by the second adjustment value until the number of the target available satellites is smaller than or equal to the preset number threshold to obtain a second cutoff angle; screening all the current available satellites according to the second cut-off angle to obtain a second screening result; the second screening result includes data for available satellites in elevation greater than the second cut-off angle.
In one embodiment, the screening unit 122 is configured to increase the first off-angle by a preset second adjustment value if the first off-angle is smaller than a preset off-angle upper limit value, so as to obtain an updated first off-angle.
In one embodiment, the screening unit 122 is configured to decrease the last updated first cut-off angle by the second adjustment value to obtain a second cut-off angle if the last updated first cut-off angle is greater than the initial cut-off angle.
In one embodiment, the screening unit 122 is configured to decrease the first cut-off angle by the first adjustment value to obtain a third cut-off angle if the number of the target available satellites is smaller than or equal to the preset number threshold; screening all the current available satellites according to the third cut-off angle to obtain a second screening result; the second screening result includes data for available satellites in elevation greater than the third cutoff angle.
In one embodiment, the positioning module 13 is further configured to perform positioning calculation according to the data of the available satellites that have passed the screening if the first screening result is that the number of the available satellites that have passed the screening is smaller than or equal to the preset number threshold.
In one embodiment, the first filtering module 11 is configured to compare the initial cut-off angle with the elevation angles of the available satellites, and determine the number of available satellites with elevation angles larger than the initial cut-off angle as the first filtering result.
In one embodiment, the positioning module 13 is configured to perform positioning solution according to data of available satellites whose elevation angles are greater than the adjusted cut-off angle by using a least square method or a kalman filtering algorithm.
The realization principle and the beneficial effect of the satellite positioning device can refer to the realization principle and the beneficial effect of the satellite positioning method, and are not described again here.
The division of the modules in the satellite positioning apparatus is only for illustration, and in other embodiments, the satellite positioning apparatus may be divided into different modules as needed to complete all or part of the functions of the satellite positioning apparatus.
For specific limitations of the satellite positioning device, reference may be made to the above limitations of the satellite positioning method, which are not described herein again. The various modules in the satellite positioning apparatus described above may be implemented in whole or in part by software, hardware, and combinations thereof. The modules can be embedded in a hardware form or independent from a processor in the computer device, and can also be stored in a memory in the computer device in a software form, so that the processor can call and execute operations corresponding to the modules.
Fig. 8 is a schematic diagram of an internal structure of an electronic device in one embodiment. As shown in fig. 8, the electronic device includes a processor and a memory connected by a system bus. Wherein, the processor is used for providing calculation and control capability and supporting the operation of the whole electronic equipment. The memory may include a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The computer program can be executed by a processor for implementing a satellite positioning method provided in the following embodiments. The internal memory provides a cached execution environment for the operating system computer programs in the non-volatile storage medium. The electronic device may be any terminal device such as a mobile phone, a tablet computer, a PDA (Personal Digital Assistant), a Point of Sales (POS), a vehicle-mounted computer, and a wearable device.
The implementation of the respective modules in the satellite positioning apparatus provided in the embodiments of the present application may be in the form of a computer program. The computer program may be run on a terminal or a server. Program modules constituted by such computer programs may be stored on the memory of the electronic device. Which when executed by a processor, performs the steps of the method described in the embodiments of the present application.
The embodiment of the application also provides a computer readable storage medium. One or more non-transitory computer-readable storage media containing computer-executable instructions that, when executed by one or more processors, cause the processors to perform the steps of the satellite positioning method.
A computer program product comprising instructions which, when run on a computer, cause the computer to perform a satellite positioning method.
Any reference to memory, storage, database or other medium used herein may include non-volatile and/or volatile memory. Non-volatile memory can include read-only memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM), which acts as external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), synchronous Link (Synchlink) DRAM (SLDRAM), Rambus (Rambus) direct RAM (RDRAM), direct bused dynamic RAM (DRDRAM), and bused dynamic RAM (RDRAM).
The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present application. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent application shall be subject to the appended claims.
Claims (10)
1. A method of satellite positioning, comprising:
screening all available satellites at present according to a preset initial cut-off angle and the elevation angle of each available satellite to obtain a first screening result; the first screening result comprises the number of available satellites that pass the screening;
if the first screening result is that the number of the available satellites passing the screening is larger than a preset number threshold, increasing the initial cut-off angle by a preset first adjusting value to obtain a first cut-off angle;
acquiring the number of target available satellites from all the current available satellites according to the first cutoff angle; the elevation angle of the target available satellite is greater than the first cutoff angle;
if the number of the target available satellites is larger than the preset number threshold, increasing the first cutoff angle by a preset second adjustment value to obtain an updated first cutoff angle, returning to execute the step of obtaining the number of the target available satellites from all the current available satellites according to the first cutoff angle, and decreasing the last updated first cutoff angle by the second adjustment value until the number of the target available satellites is smaller than or equal to the preset number threshold to obtain a second cutoff angle;
screening all the current available satellites according to the second cut-off angle to obtain a second screening result; the second screening result comprises data for available satellites in elevation greater than the second cut-off angle;
and positioning and resolving are carried out according to the second screening result.
2. The method of claim 1, wherein increasing the first cut-off angle by a preset second adjustment value to obtain an updated first cut-off angle comprises:
and if the first cut-off angle is smaller than a preset cut-off angle upper limit value, increasing the first cut-off angle by a preset second adjustment value to obtain an updated first cut-off angle.
3. The method of claim 1, wherein reducing the last updated first cutoff angle by the second adjustment value to obtain a second cutoff angle comprises:
and if the last updated first cut-off angle is larger than the initial cut-off angle, reducing the last updated first cut-off angle by the second adjusting value to obtain a second cut-off angle.
4. The method of claim 1, further comprising:
if the number of the target available satellites is smaller than or equal to the preset number threshold, reducing the first cut-off angle by the first adjusting value to obtain a third cut-off angle;
screening all the current available satellites according to the third cut-off angle to obtain a second screening result; the second screening result includes data for available satellites in elevation greater than the third cutoff angle.
5. The method of claim 1, further comprising:
and if the first screening result is that the number of the screened available satellites is smaller than or equal to a preset number threshold, performing positioning calculation according to the data of the screened available satellites.
6. The method according to claim 1, wherein the screening all available satellites currently according to the preset initial cut-off angle and the elevation angle of each available satellite to obtain a first screening result comprises:
and comparing the initial cut-off angle with the elevation angle of each available satellite, and determining the number of available satellites with the elevation angles larger than the initial cut-off angle as the first screening result.
7. The method of claim 1, wherein the second screening result comprises data for available satellites having elevation angles greater than the adjusted cut-off angle; the positioning calculation according to the second screening result includes:
and performing positioning calculation according to the data of the available satellite with the elevation angle larger than the adjusted cut-off angle by adopting a least square method or a Kalman filtering algorithm.
8. A satellite positioning apparatus, comprising:
the first screening module is used for screening all available satellites at present according to a preset initial cut-off angle and the elevation angle of each available satellite to obtain a first screening result; the first screening result comprises the number of available satellites that pass the screening;
the second screening module is used for increasing the initial cut-off angle by a preset first adjusting value to obtain a first cut-off angle if the first screening result indicates that the number of the available satellites passing the screening is greater than a preset number threshold;
acquiring the number of target available satellites from all the current available satellites according to the first cutoff angle; the elevation angle of the target available satellite is greater than the first cutoff angle;
if the number of the target available satellites is larger than the preset number threshold, increasing the first cutoff angle by a preset second adjustment value to obtain an updated first cutoff angle, returning to execute the step of obtaining the number of the target available satellites from all the current available satellites according to the first cutoff angle, and decreasing the last updated first cutoff angle by the second adjustment value until the number of the target available satellites is smaller than or equal to the preset number threshold to obtain a second cutoff angle;
screening all the current available satellites according to the second cut-off angle to obtain a second screening result; the second screening result comprises data for available satellites in elevation greater than the second cut-off angle;
and the positioning module is used for positioning and resolving according to the second screening result.
9. An electronic device comprising a memory and a processor, the memory having stored thereon a computer program, wherein the computer program, when executed by the processor, causes the processor to carry out the steps of the satellite positioning method according to any of the claims 1 to 7.
10. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of the method according to any one of claims 1 to 7.
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