CN113489509A - Time-frequency synchronization method and device among large-scale GNSS pseudolites - Google Patents
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Abstract
Description
Technical Field
The invention relates to the field of GNSS pseudo satellite navigation, in particular to a time-frequency synchronization method and device among large-scale GNSS pseudo satellites.
Background
At present, the technical field of the application of satellite navigation systems based on Beidou and GPS is more and more extensive and effective, but in areas with limited GNSS satellite signal coverage, such as high-speed tunnels, large indoor parking lots, high-rise buildings and other places, GNSS services and application are restricted. Therefore, the pseudolite positioning technology is an important means for overcoming the defects of GNSS, and the requirement of human beings on the indoor pseudolite positioning technology is more and more urgent, so that the realization of high-precision time synchronization between pseudolites at different positions is one of the core conditions for realizing precise positioning.
Common pseudolite time synchronization methods include a receiver one-way time service method and a one-way differential time synchronization technology, wherein the receiver one-way time service method is limited by low time service precision and cannot meet the requirement of high-precision indoor navigation; the latter requires precise calibration of the pseudolite position in advance, which is not favorable for large-scale pseudolite deployment and subsequent system maintenance.
Disclosure of Invention
The invention aims to provide a time-frequency synchronization method and a time-frequency synchronization device among large-scale GNSS pseudolites, and aims to solve the problems that the time service precision of the conventional pseudolite time synchronization method is not high and the high-precision indoor navigation requirement cannot be met.
In order to solve the technical problems, the invention aims to realize the following technical scheme: a time-frequency synchronization method among large-scale GNSS pseudolites is provided, which comprises the following steps:
s1: the target pseudolite receives the spread spectrum information of all adjacent pseudolites, sends the spread spectrum information to all adjacent pseudolites, and obtains first pseudo-range information P according to the received spread spectrum informationnmAnd obtaining second pseudo-range information P based on the transmitted spread spectrum informationmnWherein the spread information has a time stamp, PnmRepresenting first pseudorange information, P, from the m-th pseudolite to a target pseudolitemnSecond pseudorange information representing the second pseudorange from the target pseudolite to the mth pseudolite;
s2: the target pseudolite is based on the first pseudorange information PnmAnd said second pseudorange information PmnAnd calculating to obtain the current relative clock error information taunmWherein
S3: the target pseudolite selects a pseudolite preferentially time-frequency synchronous with the target pseudolite according to a network topology structureStar Px；
S4: the target pseudolite judges whether the current clock error information is larger than a set time-frequency synchronization threshold value;
S5：
if the current relative clock error information is larger than the time-frequency synchronization threshold, the target pseudolite performs digital frequency modulation and phase modulation processing, and returns to repeat the steps S1-S4;
and if the current relative clock difference information is less than or equal to the time-frequency synchronization threshold, directly returning to repeat the steps S1-S4.
In addition, another object of the present invention is to provide a time-frequency synchronization device between large-scale GNSS pseudolites, which comprises:
a pseudo-range information acquisition unit for receiving the spread spectrum information of all the adjacent pseudolites and transmitting the spread spectrum information to all the adjacent pseudolites by the target pseudolite, and acquiring first pseudo-range information P according to the received spread spectrum informationnmAnd obtaining second pseudo-range information P based on the transmitted spread spectrum informationmnWherein the spread information has a time stamp, PnmRepresenting first pseudorange information, P, from the m-th pseudolite to a target pseudolitemnSecond pseudorange information representing the second pseudorange from the target pseudolite to the mth pseudolite;
a unit for calculating current clock error information for said target pseudolite based on said first pseudorange information PnmAnd said second pseudorange information PmnAnd calculating to obtain the current relative clock error information taunmWherein
A selection synchronization pseudolite unit used for selecting the pseudolite P which is preferentially time-frequency synchronized with the target pseudolite according to the network topology structurex；
The judging unit is used for judging whether the current clock error information is larger than a set time-frequency synchronization threshold value or not by the target pseudolite;
the operation unit is used for performing digital frequency modulation and phase modulation on the target pseudolite if the current relative clock error information is greater than the time-frequency synchronization threshold value, and returning to the unit for repeatedly acquiring pseudo-range information, namely the judgment unit;
and if the current relative clock difference information is less than or equal to the time-frequency synchronization threshold, directly returning to a unit for repeatedly acquiring pseudo-range information, namely a judgment unit.
The embodiment of the invention discloses a time-frequency synchronization method and a time-frequency synchronization device among large-scale GNSS pseudo satellites, wherein the method comprises the following steps of S1: the target pseudolite receives the spread spectrum information of all adjacent pseudolites, sends the spread spectrum information to all adjacent pseudolites, and obtains first pseudo-range information P according to the received spread spectrum informationnmAnd obtaining second pseudo-range information P based on the transmitted spread spectrum informationmnWherein the spread information has a time stamp, PnmRepresenting first pseudorange information, P, from the m-th pseudolite to a target pseudolitemnSecond pseudorange information representing the second pseudorange from the target pseudolite to the mth pseudolite; s2: the target pseudolite is based on the first pseudorange information PnmAnd said second pseudorange information PmnAnd calculating to obtain the current relative clock error information taunmWherein
S3: the target pseudolite selects a pseudolite P which is preferentially time-frequency synchronous with the target pseudolite according to a network topological structurex(ii) a S4: the target pseudolite judges whether the current clock error information is larger than a set time-frequency synchronization threshold value; s5: if the current relative clock error information is larger than the time-frequency synchronization threshold, the target pseudolite performs digital frequency modulation and phase modulation processing, and returns to repeat the steps S1-S4; and if the current relative clock difference information is less than or equal to the time-frequency synchronization threshold, directly returning to repeat the steps S1-S4. The method has the advantages of rapidness, stability and high precision, and meets the requirement of high-precision indoor navigation.
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In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic flow chart illustrating a method for time-frequency synchronization between GNSS pseudolites in a large scale according to an embodiment of the present invention;
FIG. 2 is a schematic block diagram of a time-frequency synchronization apparatus for use between GNSS pseudolites in a large scale according to an embodiment of the present invention.
Detailed Description
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, 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.
It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
It is also to be understood that the terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the specification of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.
It should be further understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.
Referring to fig. 1, fig. 1 is a schematic flow chart illustrating a time-frequency synchronization method between large-scale GNSS pseudolites according to an embodiment of the present invention;
as shown in FIG. 1, the method includes steps S1-S5.
S1: the target pseudolite receives the spread spectrum information of all adjacent pseudolites, sends the spread spectrum information to all adjacent pseudolites, and obtains first pseudo-range information P according to the received spread spectrum informationnmAnd obtaining second pseudo-range information P based on the transmitted spread spectrum informationmnWherein the spread information has a time stamp, PnmRepresenting first pseudorange information, P, from the m-th pseudolite to a target pseudolitemnSecond pseudorange information representing the second pseudorange from the target pseudolite to the mth pseudolite;
for example, the target pseudolite is designated X2, the neighboring pseudolites to the target pseudolite X2 are X1, X3, X5, etc., and the target pseudolite X2 receives the spread spectrum information of the pseudolite X1 and obtains corresponding first pseudorange information P21Similarly, the target pseudolite X2 may also receive spread spectrum information for the corresponding pseudolite X3, X5, etc., and obtain first pseudorange information P23、P25Etc.; meanwhile, the target pseudolite X2 also transmits spread spectrum information to the neighboring pseudolite X1, and the pseudolite X1 receives the spread spectrum information transmitted by the target pseudolite X2 and acquires corresponding second pseudo-range information P12Similarly, it can be obtained that the adjacent pseudolites such as the pseudolite X3 and the pseudolite X5 respectively receive the spread spectrum information sent by the target pseudolite X2, and correspondingly obtain the second pseudo-range information P32、P52And the like.
S2: the target pseudolite is based on the first pseudorange information PnmAnd said second pseudorange information PmnAnd calculating to obtain the current relative clock error information taunmWherein
Such as the above-described relative clock difference information between target pseudolite X2 and neighboring pseudolite X1
Similarly, relative clock error information τ between the target pseudolite and the neighboring pseudolite X3 or X5 can be obtained23、τ25。
In this embodiment, the step S2 further includes:
for the current clock error information taunmPerforming linear fitting processing to obtain relative frequency difference information; wherein the linear fitting function in the linear fitting process has a clock difference τ ═ τ0+fnmt，τ0The relative frequency difference information f can be obtained by the above formulanm。
S3: the target pseudolite selects a pseudolite P which is preferentially time-frequency synchronous with the target pseudolite according to a network topological structurex；
S4: the target pseudolite judges whether the current clock error information is larger than a set time-frequency synchronization threshold value;
S5：
if the current relative clock error information is larger than the time-frequency synchronization threshold, the target pseudolite performs digital frequency modulation and phase modulation processing, and returns to repeat the steps S1-S4;
and if the current relative clock difference information is less than or equal to the time-frequency synchronization threshold, directly returning to repeat the steps S1-S4.
The step S5 includes:
identifying a target pseudolite as SmnAccording to the network topological structure, screening out pseudolites S meeting the following conditionsijWherein S ismnPseudolite representing the mth row and n columns of the layout, SijRepresenting the pseudolite in the ith row and j column, wherein m-i is more than or equal to 0 and less than or equal to 1, and n-j is more than or equal to 0 and less than or equal to 1;
if a plurality of pseudolites simultaneously satisfy the above conditions, a pseudolite with i < m is preferentially selected as a synchronous pseudolite, namely, a pseudolite with a large row number and a small row number is subjected to time-frequency synchronization.
For example, the target pseudolite X2 selects an adjacent pseudolite with priority for time-frequency synchronization according to the built-in time-frequency synchronization topology network structure, and after the synchronization pseudolite is selected, obtains the current relative clock error information according to step S2, and determines whether the current relative clock error information is greater than a set time-frequency synchronization threshold, where the time-frequency synchronization threshold may be adjusted in applicability according to the actual positioning accuracy requirement, for example, when the time-frequency synchronization threshold is set to 10ms, the contribution of the clock error between corresponding pseudolites to the positioning accuracy is 3 m.
In this embodiment, before the step S1, the method includes:
s01: calculating the initial time frequency of each pseudolite by adopting the GNSS standard time to obtain the initial time t of each pseudolite iiAnd an initial frequency fiAnd according to the initial time t of each pseudolite iiAnd an initial frequency fiCalculating the relative GNSS standard time tGNSSDeviation Δ t ofiAnd Δ fi(ii) a Wherein, Δ ti＝(ti-tGNSS)，Δfi＝(fi-fGNSS)。
S02: according to the deviation delta t of the initial time frequency of each pseudolite relative to the standard time frequency of the GNSSiAnd Δ fiAdjusting each of said pseudolite local time frequencies to compensate for said offset Δ tiAnd Δ fiTo initialize the corresponding pseudolite.
The GNSS standard time is obtained by generating local time by an atomic clock or a high-temperature crystal oscillator and then carrying out homologous transformation to an outdoor high-precision GNSS receiver to obtain the calculated standard time.
The step S01 includes:
calculating relative clock error information of the adjacent pseudolites when starting up by adopting a bidirectional pseudo-range measurement mode, and calculating the deviation delta t of the starting up time and the starting up time frequency of each pseudolite relative to the standard time of the GNSS according to the relative clock error information and the starting up time of each pseudolitei0And Δ fi0According to the deviation delta t of the starting time and the starting time frequency of each pseudolite relative to the standard time of the GNSSi0And Δ fi0Adjusting each of said pseudolite local time frequencies to compensate for said offset Δ ti0And Δ fi0So as to realize the startup time-frequency initialization of each pseudolite.
Before the step S1, the method further includes:
s01': and setting the power of each pseudolite based on the arrangement distance of the pseudolites and the dynamic sensitivity range of the GNSS receiver, so that each pseudolite can only receive the spread spectrum information of the adjacent pseudolite.
By the power control of each pseudolite, each pseudolite can only receive spread spectrum information of adjacent pseudolites, and the information transmitted by other pseudolites reaches the range that the power of the information of the target pseudolite is weak below the normal receiving sensitivity due to the long distance.
In the embodiment of the invention, under the scene that satellite signals cannot reach indoors, tunnels and the like, a time-frequency synchronization method among large-scale GNSS pseudolites is adopted, so that the pseudolite time-frequency synchronization precision is higher and can reach a sub-ns magnitude; meanwhile, the time-frequency synchronization method which can be realized by the method does not need to calibrate the position of the pseudo satellite; and the method can provide a plurality of autonomous time-frequency synchronization links, avoid the problem of network time-frequency synchronization interruption caused by individual pseudolite faults, and reduce the system maintenance cost.
The embodiment of the invention also provides a time-frequency synchronization device among the large-scale GNSS pseudolites, which is used for executing any embodiment of the time-frequency synchronization method among the large-scale GNSS pseudolites. Specifically, referring to fig. 2, fig. 2 is a schematic block diagram of a time-frequency synchronization apparatus between large-scale GNSS pseudolites according to an embodiment of the present invention.
As shown in fig. 2, theapparatus 500 for time-frequency synchronization between large-scale GNSS pseudolites comprises:
a pseudo-rangeinformation obtaining unit 501, configured to receive spreading information of all neighboring pseudolites and transmit the spreading information to all neighboring pseudolites by the target pseudolite, and obtain first pseudo-range information P according to the received spreading informationnmAnd obtaining second pseudo-range information P based on the transmitted spread spectrum informationmnWherein the spread information has a time stamp, PnmRepresenting first pseudorange information, P, from the m-th pseudolite to a target pseudolitemnSecond pseudorange information representing the second pseudorange from the target pseudolite to the mth pseudolite;
unit for calculating current clock error information502 for said target pseudolite based on said first pseudorange information PnmAnd said second pseudorange information PmnAnd calculating to obtain the current relative clock error information taunmWherein
A selectsync pseudolite unit 503 for the target pseudolite to select a pseudolite P preferentially time-frequency synchronized with the target pseudolite according to the network topologyx；
A determiningunit 504, configured to determine whether the current clock offset information is greater than a set time-frequency synchronization threshold by the target pseudolite;
anoperation unit 505, configured to perform digital frequency modulation and phase modulation on the target pseudolite if the current relative clock difference information is greater than the time-frequency synchronization threshold, and return to the unit 501-determiningunit 504 for repeatedly acquiring pseudo-range information;
and if the current relative clock difference information is less than or equal to the time-frequency synchronization threshold, directly returning to the unit for repeatedly acquiring pseudo-range information 501-thejudging unit 504.
The time-frequency synchronization device among the large-scale GNSS pseudolites enables the pseudolites to have higher time-frequency synchronization precision and can reach a sub-ns magnitude; the time frequency synchronization method can be realized without calibrating the position of the pseudo satellite; and a plurality of autonomous time-frequency synchronization links can be provided, the problem of network time-frequency synchronization interruption caused by individual pseudolite faults is avoided, and the system maintenance cost is reduced.
In one embodiment, the method further comprises:
a calculating deviation unit for calculating the initial time frequency of each pseudolite by adopting the GNSS standard time to obtain the initial time t of each pseudolite iiAnd an initial frequency fiAnd according to the initial time t of each pseudolite iiAnd an initial frequency fiCalculating the deviation delta t relative to the standard time of the GNSSiAnd Δ fi；
An adjusting unit: for correlating GNSS standards according to the initial time frequency of each of the pseudolitesDeviation of time frequency Δ tiAnd Δ fiAdjusting each of said pseudolite local time frequencies to compensate for said offset Δ tiAnd Δ fiTo initialize the corresponding pseudolite.
A power control unit: the method is used for setting the power of each pseudolite based on the arrangement distance of the pseudolites and the dynamic sensitivity range of the GNSS receiver, so that each pseudolite can only receive the spread spectrum information of the adjacent pseudolites.
A preference selection unit: for identifying a target pseudolite as SmnAccording to the network topological structure, screening out pseudolites S meeting the following conditionsijWherein S ismnPseudolite representing the mth row and n columns of the layout, SijRepresenting the pseudolite in the ith row and j column, wherein m-i is more than or equal to 0 and less than or equal to 1, and n-j is more than or equal to 0 and less than or equal to 1;
if a plurality of pseudolites simultaneously satisfy the above condition, a pseudolite with i < m is preferentially selected as the sync pseudolite.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
While the invention has been described with reference to specific embodiments, the invention is not limited thereto, and various equivalent modifications and substitutions can be easily made by those skilled in the art within the technical scope of the invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (10)
1. A time-frequency synchronization method among large-scale GNSS pseudolites is characterized by comprising the following steps:
s1: the target pseudolite receives the spread spectrum information of all adjacent pseudolites, sends the spread spectrum information to all adjacent pseudolites, and obtains first pseudo-range information P according to the received spread spectrum informationnmAnd acquiring from the transmitted spread spectrum informationSecond pseudorange information PmnWherein the spread information has a time stamp, PnmRepresenting first pseudorange information, P, from the m-th pseudolite to a target pseudolitemnSecond pseudorange information representing the second pseudorange from the target pseudolite to the mth pseudolite;
s2: the target pseudolite is based on the first pseudorange information PnmAnd said second pseudorange information PmnAnd calculating to obtain the current relative clock error information taunmWherein
S3: the target pseudolite selects a pseudolite P which is preferentially time-frequency synchronous with the target pseudolite according to a network topological structurex；
S4: the target pseudolite judges the current clock error information taunxWhether the time frequency synchronization threshold is larger than the set time frequency synchronization threshold or not;
S5：
if the current relative clock error information is larger than the time-frequency synchronization threshold, the target pseudolite performs digital frequency modulation and phase modulation processing, and returns to repeat the steps S1-S4;
and if the current relative clock difference information is less than or equal to the time-frequency synchronization threshold, directly returning to repeat the steps S1-S4.
2. The method for time-frequency synchronization between GNSS pseudolites in large scale according to claim 1, wherein step S1 is preceded by:
s01: calculating the initial time frequency of each pseudolite by adopting the GNSS standard time to obtain the initial time t of each pseudolite iiAnd an initial frequency fiAnd according to the initial time t of each pseudolite iiAnd an initial frequency fiCalculating the deviation delta t relative to the standard time of the GNSSiAnd Δ fi；
S02: according to the deviation delta t of the initial time frequency of each pseudolite relative to the standard time frequency of the GNSSiAnd Δ fiAdjusting each of said pseudolitesLocal time frequency, compensating for said deviation Δ tiAnd Δ fiTo initialize the corresponding pseudolite.
3. The method of claim 2, wherein the GNSS standard time is generated by an atomic clock or a high-temperature crystal oscillator, and then is homologous to an outdoor high-precision GNSS receiver to obtain the calculated standard time.
4. The method for time-frequency synchronization between GNSS pseudolites in large scale according to claim 1, wherein step S1 is preceded by:
s01': and setting the power of each pseudolite based on the arrangement distance of the pseudolites and the dynamic sensitivity range of the GNSS receiver, so that each pseudolite can only receive the spread spectrum information of the adjacent pseudolite.
5. The method according to claim 1, wherein the step S2 further comprises:
for the current clock error information taunmAnd performing linear fitting processing to obtain relative frequency difference information.
6. The method according to claim 1, wherein the step S5 comprises:
identifying a target pseudolite as SmnAccording to the network topological structure, screening out pseudolites S meeting the following conditionsijWherein S ismnPseudolite representing the mth row and n columns of the layout, SijRepresenting the pseudolite in the ith row and j column, wherein m-i is more than or equal to 0 and less than or equal to 1, and n-j is more than or equal to 0 and less than or equal to 1;
if a plurality of pseudolites simultaneously satisfy the above condition, a pseudolite with i < m is preferably selected as the sync pseudolite.
7. A time-frequency synchronization device between large-scale GNSS pseudolites is characterized by comprising:
a pseudo-range information acquisition unit for receiving the spread spectrum information of all the adjacent pseudolites and transmitting the spread spectrum information to all the adjacent pseudolites by the target pseudolite, and acquiring first pseudo-range information P according to the received spread spectrum informationnmAnd obtaining second pseudo-range information P based on the transmitted spread spectrum informationmnWherein the spread information has a time stamp, PnmRepresenting first pseudorange information, P, from the m-th pseudolite to a target pseudolitemnSecond pseudorange information representing the second pseudorange from the target pseudolite to the mth pseudolite;
a unit for calculating current clock error information for said target pseudolite based on said first pseudorange information PnmAnd said second pseudorange information PmnAnd calculating to obtain the current relative clock error information taunmWherein
A selection synchronization pseudolite unit used for selecting the pseudolite P which is preferentially time-frequency synchronized with the target pseudolite according to the network topology structurex；
The judging unit is used for judging whether the current clock error information is larger than a set time-frequency synchronization threshold value or not by the target pseudolite;
the operation unit is used for performing digital frequency modulation and phase modulation on the target pseudolite if the current relative clock error information is greater than the time-frequency synchronization threshold value, and returning to the unit for repeatedly acquiring pseudo-range information, namely the judgment unit;
and if the current relative clock difference information is less than or equal to the time-frequency synchronization threshold, directly returning to a unit for repeatedly acquiring pseudo-range information, namely a judgment unit.
8. The inter-GNSS pseudolite time-frequency synchronization device of claim 7, comprising:
a calculating deviation unit for calculating the initial time frequency of each pseudolite by adopting the GNSS standard time to obtain the initial time frequency of each pseudolite iInitial time tiAnd an initial frequency fiAnd according to the initial time t of each pseudolite iiAnd an initial frequency fiCalculating the deviation delta t relative to the standard time of the GNSSiAnd Δ fi；
An adjusting unit: for determining the deviation Δ t of the initial time frequency of each of the pseudolites from the standard time frequency of GNSSiAnd Δ fiAdjusting each of said pseudolite local time frequencies to compensate for said offset Δ tiAnd Δ fiTo initialize the corresponding pseudolite.
9. The inter-GNSS pseudolite time-frequency synchronization device of claim 8, comprising:
a power control unit: the method is used for setting the power of each pseudolite based on the arrangement distance of the pseudolites and the dynamic sensitivity range of the GNSS receiver, so that each pseudolite can only receive the spread spectrum information of the adjacent pseudolites.
10. The inter-GNSS pseudolite time-frequency synchronization device of claim 9, comprising:
a preference selection unit: for identifying a target pseudolite as SmnAccording to the network topological structure, screening out pseudolites S meeting the following conditionsijWherein S ismnPseudolite representing the mth row and n columns of the layout, SijRepresenting the pseudolite in the ith row and j column, wherein m-i is more than or equal to 0 and less than or equal to 1, and n-j is more than or equal to 0 and less than or equal to 1;
if a plurality of pseudolites simultaneously satisfy the above condition, a pseudolite with i < m is preferably selected as the sync pseudolite.
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Citations (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050015198A1 (en)* | 2001-11-06 | 2005-01-20 | Chang-Don Kee | Pseudolite-based precise positioning system with synchronised pseudolites |
| US20070257831A1 (en)* | 2006-04-28 | 2007-11-08 | Loctronix Corporation | System and method for positioning in configured environments |
| CN101158719A (en)* | 2007-11-16 | 2008-04-09 | 上海伽利略导航有限公司 | False satellite sub-decimeter level indoor position location system and carrier phase positioning method thereof |
| US20110037648A1 (en)* | 2009-08-17 | 2011-02-17 | Electronics And Telecommunications Research Institute | Apparatus for transmitting pseudollite signal based on single clock and positioning system using the same |
| CN103630915A (en)* | 2012-08-24 | 2014-03-12 | 陈曦 | Method for navigation positioning by use of digital frequency modulation broadcasting |
| CN104062895A (en)* | 2014-06-26 | 2014-09-24 | 桂林电子科技大学 | Pseudolite time synchronization method and positioning method thereof |
| CN204287484U (en)* | 2014-06-26 | 2015-04-22 | 桂林电子科技大学 | A kind of anti-deception pseudolite systems |
| CN105182382A (en)* | 2015-08-05 | 2015-12-23 | 中国电子科技集团公司第五十四研究所 | Centimeter-level positioning method of pseudo satellite |
| WO2015196723A1 (en)* | 2014-06-27 | 2015-12-30 | 中兴通讯股份有限公司 | Indoor base station synchronisation method, apparatus, and system |
| CN105680976A (en)* | 2016-03-29 | 2016-06-15 | 中国电子科技集团公司第二十九研究所 | A Distributed Network Time Synchronization Method |
| CN106452645A (en)* | 2016-10-26 | 2017-02-22 | 西安空间无线电技术研究所 | Satellite group network time synchronization method based on cross-layer design |
| CN106533529A (en)* | 2016-09-27 | 2017-03-22 | 北京无线电计量测试研究所 | Modulation and demodulation system and method for two-way time comparison of satellite |
| CN106595667A (en)* | 2016-12-07 | 2017-04-26 | 中国电子科技集团公司第五十四研究所 | Mutual synchronization-based indoor pseudolite double-point positioning system and method |
| CN106597474A (en)* | 2016-12-28 | 2017-04-26 | 格星微电子科技成都有限公司 | Indoor GNSS pseudo-satellite networking method |
| CN109061696A (en)* | 2018-09-28 | 2018-12-21 | 中国人民解放军61540部队 | A kind of method of determining navigation satellite track and clock deviation |
| CN109655846A (en)* | 2019-01-30 | 2019-04-19 | 清华大学 | A kind of multistation difference post-processing high-precision time synchronization method and system |
| CN110658498A (en)* | 2019-09-02 | 2020-01-07 | 中国航天系统科学与工程研究院 | Time-frequency synchronization method for networked radar system |
| CN110784277A (en)* | 2019-10-29 | 2020-02-11 | 北京无线电计量测试研究所 | Motion platform synchronous compensation method based on satellite two-way time comparison |
| CN110912636A (en)* | 2019-11-20 | 2020-03-24 | 北京无线电计量测试研究所 | Multi-station real-time bidirectional time comparison method |
| CN111275757A (en)* | 2020-01-08 | 2020-06-12 | 中国电子科技集团公司第五十四研究所 | A pseudolite site simulation layout method based on DEM data processing |
| CN111948674A (en)* | 2020-07-02 | 2020-11-17 | 中国人民解放军61081部队 | Pseudo satellite and Beidou satellite signal compatibility method based on user experience |
- 2021
- 2021-07-06CNCN202110761688.5Apatent/CN113489509B/enactiveActive
Patent Citations (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050015198A1 (en)* | 2001-11-06 | 2005-01-20 | Chang-Don Kee | Pseudolite-based precise positioning system with synchronised pseudolites |
| US20070257831A1 (en)* | 2006-04-28 | 2007-11-08 | Loctronix Corporation | System and method for positioning in configured environments |
| CN101158719A (en)* | 2007-11-16 | 2008-04-09 | 上海伽利略导航有限公司 | False satellite sub-decimeter level indoor position location system and carrier phase positioning method thereof |
| US20110037648A1 (en)* | 2009-08-17 | 2011-02-17 | Electronics And Telecommunications Research Institute | Apparatus for transmitting pseudollite signal based on single clock and positioning system using the same |
| CN103630915A (en)* | 2012-08-24 | 2014-03-12 | 陈曦 | Method for navigation positioning by use of digital frequency modulation broadcasting |
| CN104062895A (en)* | 2014-06-26 | 2014-09-24 | 桂林电子科技大学 | Pseudolite time synchronization method and positioning method thereof |
| CN204287484U (en)* | 2014-06-26 | 2015-04-22 | 桂林电子科技大学 | A kind of anti-deception pseudolite systems |
| WO2015196723A1 (en)* | 2014-06-27 | 2015-12-30 | 中兴通讯股份有限公司 | Indoor base station synchronisation method, apparatus, and system |
| CN105182382A (en)* | 2015-08-05 | 2015-12-23 | 中国电子科技集团公司第五十四研究所 | Centimeter-level positioning method of pseudo satellite |
| CN105680976A (en)* | 2016-03-29 | 2016-06-15 | 中国电子科技集团公司第二十九研究所 | A Distributed Network Time Synchronization Method |
| CN106533529A (en)* | 2016-09-27 | 2017-03-22 | 北京无线电计量测试研究所 | Modulation and demodulation system and method for two-way time comparison of satellite |
| CN106452645A (en)* | 2016-10-26 | 2017-02-22 | 西安空间无线电技术研究所 | Satellite group network time synchronization method based on cross-layer design |
| CN106595667A (en)* | 2016-12-07 | 2017-04-26 | 中国电子科技集团公司第五十四研究所 | Mutual synchronization-based indoor pseudolite double-point positioning system and method |
| CN106597474A (en)* | 2016-12-28 | 2017-04-26 | 格星微电子科技成都有限公司 | Indoor GNSS pseudo-satellite networking method |
| CN109061696A (en)* | 2018-09-28 | 2018-12-21 | 中国人民解放军61540部队 | A kind of method of determining navigation satellite track and clock deviation |
| CN109655846A (en)* | 2019-01-30 | 2019-04-19 | 清华大学 | A kind of multistation difference post-processing high-precision time synchronization method and system |
| CN110658498A (en)* | 2019-09-02 | 2020-01-07 | 中国航天系统科学与工程研究院 | Time-frequency synchronization method for networked radar system |
| CN110784277A (en)* | 2019-10-29 | 2020-02-11 | 北京无线电计量测试研究所 | Motion platform synchronous compensation method based on satellite two-way time comparison |
| CN110912636A (en)* | 2019-11-20 | 2020-03-24 | 北京无线电计量测试研究所 | Multi-station real-time bidirectional time comparison method |
| CN111275757A (en)* | 2020-01-08 | 2020-06-12 | 中国电子科技集团公司第五十四研究所 | A pseudolite site simulation layout method based on DEM data processing |
| CN111948674A (en)* | 2020-07-02 | 2020-11-17 | 中国人民解放军61081部队 | Pseudo satellite and Beidou satellite signal compatibility method based on user experience |
Non-Patent Citations (2)
| Title |
|---|
| YOUMING LI.ETC: "《Research on Near-far Effect and anti-impact noise interference pseudo-code sequence blind estimation algorithm in Pseudo Satellite System》", 《2020 IEEE 3RD INTERNATIONAL CONFERENCE ON INFORMATION COMMUNICATION AND SIGNAL PROCESSING (ICICSP)》* |
| 袁江红: "GNSS接收机伪距测量对定位的影响探讨", 《四川建材》* |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114236584A (en)* | 2021-11-30 | 2022-03-25 | 上海闻泰信息技术有限公司 | Positioning method, system, electronic device, storage medium and program product |
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