CN109870898B - GNSS time service receiver clock combination regulation and control method and system based on PPP - Google Patents
GNSS time service receiver clock combination regulation and control method and system based on PPP Download PDFInfo
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Abstract
The invention discloses a GNSS time service receiver clock combination regulation and control method and system based on PPP, which comprises a clock characteristic modeling stage and a clock regulation and control process, wherein the clock characteristic is modeled when a PPP module works normally, the clock regulation and control method comprises the steps of regulating and controlling a clock according to a clock difference estimated by the PPP module, and recording the clock difference estimated by each epoch PPP module and a corresponding output clock control quantity; when the time service receiver works for more than a preset first time period, starting to perform clock characteristic modeling, and fitting clock frequency drift based on clock control quantity; when the time service receiver works for more than a preset second time period, modeling the long-period error item by using clock control quantity; and when the PPP module cannot work normally, calculating the clock difference of the receiver through the clock characteristic modeling result, and continuously regulating and controlling the clock. The method can be realized in the GNSS time service receiver based on the PPP technology, additional equipment is not needed, and the time service continuity and stability of the GNSS time service receiver can be improved only through the combination of the PPP technology and the fitting process.
Description
Technical Field
The invention belongs to the technical field of Global Navigation Satellite System (GNSS), and particularly relates to a clock combination regulation and control technical scheme of a GNSS time service receiver based on a precision Point Positioning technology (PPP).
Background
The Global Navigation Satellite System (GNSS) is a satellite-based radio Positioning System, and mainly includes the united states Global Positioning System (GPS), the Beidou (BDS) in china, the GLONASS (GLONASS) in russia, and the Galileo (Galileo) in europe. Currently, GNSS plays a very critical role in mapping, navigation and timing. In the time service field, the GNSS receiver has the characteristics of high precision, low cost, stability and the like when used for time service, and the time service receiver is more and more widely applied in the time service field.
The traditional GNSS time service receiver mainly uses a pseudo-range single-point positioning technology to estimate clock error, the estimation precision of the clock error is about 20ns, and the time service precision is 20 ns-50 ns. In order to improve the accuracy of time service, a GNSS time service receiver based on the PPP technology has been developed, the estimation accuracy of the clock error is about 0.2ns, and the time service accuracy is less than 2ns, but the stable operation of the time service receiver depends on the satellite correction information (including the satellite orbit and the clock error correction) received from the service end, and when a problem occurs in the network or the service end, the GNSS time service receiver based on the PPP technology cannot provide stable clock error, which may seriously affect the time service accuracy. The clock in the general time service receiver has higher stability, and if some characteristics of the atomic clock can be modeled when the PPP module works normally, the clock can be regulated and controlled by using the parameters obtained by modeling in the time period when the PPP module cannot work, so that more stable time service is continuously provided.
Disclosure of Invention
Aiming at the situation that the time service receiver can not finish high-precision time service work when a PPP module can not work normally in the GNSS time service receiver based on the PPP technology, the invention provides a clock combination regulation and control method of the GNSS time service receiver based on the PPP technology, which makes full use of the characteristic of high precision of the PPP estimated clock difference to accurately model the clock characteristics, regulates and controls the clock by using a clock model when the PPP module can not work normally, and transfers the clock control right to the PPP module when the PPP module recovers to work normally.
In order to solve the technical problems, the invention adopts the following technical scheme:
a GNSS time service receiver clock combination regulation and control method based on PPP, the GNSS time service receiver includes PPP module, characterized by that: comprises a clock characteristic modeling stage and a clock regulation and control process,
a clock characteristic modeling process for modeling a clock characteristic when the PPP module is operating normally, comprising the steps of,
step SA1, regulating and controlling the clock according to the clock error estimated by the PPP module, and recording the clock error estimated by the PPP module of each epoch and the corresponding output clock control quantity;
step SA2, when the time service receiver works for more than a preset first time period, starting to perform clock characteristic modeling, and fitting clock frequency drift based on clock control quantity; when the time service receiver works for more than a preset second time period, modeling the long-period error item by using clock control quantity;
a clock regulation process for calculating a receiver clock difference through a clock characteristic modeling result when the PPP module cannot work normally, thereby continuing to regulate the clock, comprising the following steps,
step SB1, when the PPP module can not work normally, estimating the clock frequency deviation according to the fitted clock frequency drift and the long period error term, and estimating the clock error;
step SB2, calculating the clock control quantity according to the clock difference obtained in step SB 1;
at step SB3, the clock control amount calculated at step SB2 is rounded to an integer and sent to the clock as a final result.
In step SA2, the clock characteristic modeling is started when the timing receiver operates for a first time period, which is set to be longer than a predetermined first time period, and the clock characteristic modeling is performed,
step SA2.1, preprocessing the recorded clock control quantity, and shaving out gross error data and divergence data;
step SA2.2, modeling the clock characteristics by the preprocessed clock control quantity, fitting by a linear function as follows, wherein the parameter to be fitted is clock frequency Drift,
wherein the content of the first and second substances,
indicating the amount of clock control applied to the clock at time k, t indicating the corresponding time value,
indicating the initiation of a clock control quantityThe value is set as the clock control amount corresponding to the nominal frequency of the clock, and m represents the scale factor of the clock control amount.
And when the time service receiver works for a second time period exceeding the preset time period, the clock control quantity is used for modeling the long-period error term, and the long-period error term is realized by adopting a polynomial fitting mode.
Moreover, the implementation of step SB1 includes the steps of,
step SB1.1, it is assumed that the PPP module cannot normally work after the moment k, and the clock frequency offset f at the moment is consideredkTo 0, the clock frequency offset f at time k +1 is calculatedk+1As follows below, the following description will be given,
fk+1＝fk+Drift×T+wk+1
wherein Drift is the frequency Drift of the fitting, T is the sampling interval, and wk+1Is a long period error term;
in step SB1.2, the clock offset is estimated as follows,
Tk+1＝Tk+(fk+1+fk)/2×T
wherein, Tk+1Receiver clock error, T, representing the estimate of time k +1kRepresenting the receiver clock difference at time k. In step SB2, the clock control amount is calculated from the clock difference obtained in step SB1 and implemented by a second-order phase-locked loop.
The invention provides a GNSS time service receiver clock combination regulation and control system based on PPP, wherein the GNSS time service receiver comprises a PPP module, a clock characteristic modeling module and a clock regulation and control module,
a clock characteristic modeling module for modeling the clock characteristic when the PPP module is operating normally, including the following units,
a unit SA1, configured to regulate and control the clock according to the clock difference estimated by the PPP module, and record the clock difference estimated by the PPP module for each epoch and the corresponding output clock control amount;
a unit SA2, configured to start clock characteristic modeling after the time service receiver operates over a preset first time period, and fit a clock drift based on a clock control quantity; when the time service receiver works for more than a preset second time period, modeling the long-period error item by using clock control quantity;
the clock regulation and control module is used for calculating the clock difference of the receiver through the clock characteristic modeling result when the PPP module can not work normally so as to continuously regulate and control the clock and comprises the following units,
a unit SB1, configured to estimate, when the PPP module cannot normally operate, a clock frequency offset according to the fitted clock frequency drift and the long-period error term, and estimate a clock offset;
a unit SB2 for calculating the clock control quantity according to the clock difference obtained by the unit SB 1;
a unit SB3 for rounding the clock control amount calculated according to the unit SB2 to an integer and sending to the clock as a final result.
Furthermore, the unit SA2 includes the following sub-units,
the subunit SA2.1 is configured to perform preprocessing on the recorded clock control variable, and shave out gross error data and divergence data;
a subunit SA2.2 for modeling the clock characteristics with the preprocessed clocked quantities, comprising fitting with a linear function, the parameter to be fitted being the clock Drift,
wherein the content of the first and second substances,
indicating the amount of clock control applied to the clock at time k, t indicating the corresponding time value,
the initial value of the clock control quantity is represented as the clock control quantity corresponding to the nominal frequency of the clock, and m represents the scale factor of the clock control quantity.
And when the time service receiver works for a second time period exceeding the preset time period, the clock control quantity is used for modeling the long-period error term, and the long-period error term is realized by adopting a polynomial fitting mode.
Furthermore, the unit SB1 includes the following sub-units,
a subunit SB1.1, configured to set that the PPP module cannot normally operate after time k, and consider that the clock frequency offset f at that timekTo 0, the clock frequency offset f at time k +1 is calculatedk+1As follows below, the following description will be given,
fk+1＝fk+Drift×T+wk+1
wherein Drift is the frequency Drift of the fitting, T is the sampling interval, and wk+1Is a long period error term;
subunit SB1.2, for clock offset estimation,
Tk+1＝Tk+(fk+1+fk)/2×T
wherein, Tk+1Receiver clock error, T, representing the estimate of time k +1kRepresenting the receiver clock difference at time k.
Furthermore, the unit SB2 calculates the clock control amount according to the clock difference obtained by the unit SB1, and the clock control amount is realized by a second-order phase-locked loop.
Compared with the prior art, the invention has the following characteristics:
1. the GNSS time service receiver can continuously provide high-precision time service when a network is interrupted or a server broadcasting correction numbers collapses only by adding a clock model fitting module without additional equipment, and the stability of the GNSS time service receiver is improved.
2. When the calculation result of the PPP module has gross error or re-convergence, the clock error calculated by using the clock characteristic can be used for clock regulation and control, so that the high-precision time service continuity of the GNSS time service receiver is improved.
2. The method can be used in the time service field but not limited to the time service field, and can also be used in the crystal oscillator test field, and the test and the evaluation of the clock stability are completed through the high-precision clock error estimated by the PPP module.
Drawings
FIG. 1 is a schematic diagram of a system according to an embodiment of the invention.
Detailed Description
The technical scheme of the invention is explained in the following by combining the drawings and the embodiment.
According to the invention, the clock characteristic fitting module is added in the GNSS time service receiver based on PPP, when the PPP can not provide the clock difference of the high-precision receiver, the clock model obtained by fitting is used for calculating the clock difference of the receiver, and a mode that the PPP module and the clock characteristic fitting module are combined to regulate and control the clock is formed, so that the GNSS time service machine has the high-precision time service function under the conditions that the correction number is interrupted (network interruption or server side collapse), signals are interfered and the calculation result of the PPP module has gross error or heavy convergence.
The embodiment provides a clock combination regulation and control method of a GNSS time service receiver based on PPP, the GNSS time service receiver comprises a PPP module, a clock characteristic modeling stage and a clock regulation and control process,
the invention provides a clock fitting method of a GNSS time service receiver based on PPP technology in a clock characteristic modeling stage, which is used for modeling clock characteristics when a PPP module works normally and comprises the following steps:
SA1 regulates and controls the clock according to the clock difference estimated by the PPP module to keep the clock difference near 0, and records the clock difference estimated by the PPP module of each epoch and the corresponding output clock control quantity;
in specific implementation, the implementation of the PPP module to estimate the clock error is the prior art, and the present invention is not described in detail.
Further, step SA1 includes:
SA 1.1 when the time service receiver is just started, the clock difference of the receiver is large, and a large-step regulation clock is needed to ensure that the clock difference is rapidly converged to 0;
the clock error precision output by the SA 1.2PPP module also has a convergence process, so the clock control quantity recorded half an hour before starting the computer is unavailable;
SA2 begins to model the clock characteristic when the time service receiver works for more than a preset first time period, and fits the clock frequency drift based on the clock control quantity; and when the time service receiver works for more than a preset second time period, modeling the long-period error item by using the clock control quantity.
The second time period is greater than the first time period and is used for obtaining modeling data of the long-period error term.
In an embodiment, the first time period is taken to be one day and the second time period is taken to be three days.
When the time service receiver works for more than one day, the clock characteristic modeling is started;
further, step SA2 includes:
SA2.1 pre-processes the clocked quantities recorded in step SA1 to remove significant gross and diffuse data;
SA2.2 models the clock characteristics by using the preprocessed clock control quantity, and the value of the clock control quantity can be used for representing the rough frequency offset of each epoch. Therefore, a linear function can be used for fitting, the parameter to be fitted is clock frequency Drift Drift, and the fitting function is formula (1)
Wherein the content of the first and second substances,
a clock control amount (the value is an integer) indicating that the time k is applied to the clock, and the result recorded in step SA1 may be used; t represents the value of the corresponding time of day,
the initial value of the clock control amount is represented as the clock control amount corresponding to the nominal frequency of the clock, and m represents the scale factor of the clock control amount and represents the frequency deviation corresponding to the minimum step 1 of the control amount. In specific implementation, the calculated clock control quantity is applied to the clock and is usually realized by adopting a DA module (digital-analog conversion module), and the value m can be calculated by dividing the length of the electric regulation range of the selected clock by the number of DA bits.
When the time service receiver works for more than 3 days, a clock control quantity can be used for modeling a long-period error item caused by environmental factors.
In particular, long-period error term modeling can be realized by adopting a polynomial fitting mode, such as a cubic polynomial.
In specific implementation, the clock fitting method can be realized in a software modularization mode, and a clock characteristic fitting module is provided.
The invention provides a clock regulation and control technology for estimating clock error by using a clock model, which can adopt a clock characteristic fitting module for further calculating the receiver clock error by using a clock model obtained by clock characteristic modeling when a PPP module can not work normally so as to continuously regulate and control a clock, and comprises the following steps:
SB1 when the PPP module can not work normally, the clock characteristic fitting module starts to estimate the clock error;
further, step SB1 includes:
SB1.1 presumes that PPP module can't work normally after a certain moment k, think clock frequency deviation f at this momentkThe frequency offset f at the moment of k +1 can be calculated according to the frequency drift of the clock estimated by the clock characteristic fitting module and information such as long period error items caused by environmental factorsk+1；
fk+1＝fk+Drift×T+wk+1 (2)
Wherein Drift is the frequency Drift fitted by the clock characteristic fitting module according to the formula (1), T is the sampling interval,
wk+1and if the time service receiver works for more than 3 days, the long period error item estimated according to SA2.3 modeling can be adopted, and otherwise, the value is 0.
SB1.2 after calculating the clock frequency deviation, since the integral of the frequency deviation is equal to the phase error, here the average frequency deviation (f) is usedk+1+fk)/2The integral of the frequency deviation is solved by multiplying by time, so the calculation formula of the clock difference at the time k +1 is as follows:
Tk+1＝Tk+(fk+1+fk)/2×T (3)
wherein, Tk+1Receiver clock error, T, representing the estimate of time k +1kRepresenting the receiver clock difference at time k. The first time step SB1 is performed, TkWith the clock characteristic fitting module of the first embodiment, the clock difference estimated by the PPP module recorded in step SA1 is used, and thenWhen iterating, TkThe result of the calculation using equation (3) at the previous time is used.
SB2 clock difference T estimated by the clock characteristic fitting Module according to step SB1k+1Calculating the clock control quantity at the time of k +1
This can be done using known techniques, for example by means of a second order Phase Locked Loop (PLL).
SB3 rounds the clock control amount at the time k +1 calculated at S2 to an integer, sends it to the clock as a final result, and updates the frequency deviation at this time, as follows:
if the PPP module has not recovered normal operation, let k be k +1, and iteratively execute steps SB1 to SB3 according to the updated frequency offset to calculate the clock control amount at the next time.
The step calculates the receiver clock difference according to the fitted frequency deviation of the clock and the long period error term, and has higher precision in a short time.
In specific implementation, the technical scheme can adopt a computer software technology to realize an automatic operation process, and can also adopt a modularized mode to provide a corresponding system. For example, a clock combination regulation and control system of a GNSS time service receiver based on PPP is provided, the GNSS time service receiver comprises a PPP module, a clock characteristic modeling module and a clock regulation and control module,
a clock characteristic modeling module for modeling the clock characteristic when the PPP module is operating normally, including the following units,
a unit SA1, configured to regulate and control the clock according to the clock difference estimated by the PPP module, and record the clock difference estimated by the PPP module for each epoch and the corresponding output clock control amount;
a unit SA2, configured to start clock characteristic modeling after the time service receiver operates over a preset first time period, and fit a clock drift based on a clock control quantity; when the time service receiver works for more than a preset second time period, modeling the long-period error item by using clock control quantity;
the clock regulation and control module is used for calculating the clock difference of the receiver through the clock characteristic modeling result when the PPP module can not work normally so as to continuously regulate and control the clock and comprises the following units,
a unit SB1, configured to estimate, when the PPP module cannot normally operate, a clock frequency offset according to the fitted clock frequency drift and the long-period error term, and estimate a clock offset;
a unit SB2 for calculating the clock control quantity according to the clock difference obtained by the unit SB 1;
a unit SB3 for rounding the clock control amount calculated according to the unit SB2 to an integer and sending to the clock as a final result.
The specific implementation of each module can refer to corresponding steps, and the detailed description of the invention is omitted.
In specific implementation, the system module may be divided in other manners, referring to fig. 1, an embodiment provides a GNSS time service receiver clock combination regulation and control system based on a PPP technique, for controlling switching between two clock regulation and control manners in a running process of a time service receiver, including:
the first module is used for receiving the satellite observation value, estimating the clock error of the receiver by using a PPP technology and can be realized by using a PPP module of a GNSS time service receiver in the prior art;
the second module is used for calculating the clock error of the receiver according to the clock model obtained by modeling, namely a clock characteristic fitting module;
further, the second module further comprises sub-modules:
the first submodule is used for fitting the frequency drift of the clock and a long-period error term caused by environmental factors according to the recorded clock control quantity;
the second sub-module is used for calculating the clock offset according to the fitted information such as clock frequency drift and the like when the PPP module cannot work normally;
the third module, namely the PPP result quality control module, is used for monitoring the working condition of the PPP module in real time, when the PPP module can't work normally, notify the fourth module to change the second module as the input source, when the PPP module can work normally notify the fourth module to switch the input source to the first module;
the fourth module is used for generating clock control quantity according to the receiver clock difference output by the first module or the second module and sending the clock control quantity to a clock to finish the function of regulating and controlling the clock, and the specific strategy of the fourth module is controlled by the third module;
for reference, the working flow of the GNSS time service receiver based on the PPP technology with the clock characteristic fitting module added is as follows:
when the 1 GNSS time service receiver is started, the clock difference is estimated by using the first module, namely the PPP module, and the clock is controlled by using a larger regulation step, so that the clock difference of the receiver approaches to 0 quickly.
2, after the clock difference of the receiver reaches the vicinity of 0, the clock control quantity is generated by a second-order phase-locked loop by taking the clock difference of the receiver as input, so that the clock difference of the receiver is stabilized at the vicinity of 0.
And 3, recording the clock control amount generated by each epoch.
4 when the time service receiver works for more than one day, the recorded clock control quantity is preprocessed, and the following data need to be eliminated: the receiver just starts the data of the time period of clock error unconvergence, the data of the PPP module positioning result in the convergence process and the data of the PPP module positioning result in the gross error.
And 5, fitting the clock frequency drift by the preprocessed data according to the model established by the formula (1), wherein an adopted fitting method is a polynomial fitting method.
And 6, monitoring the working state of the PPP module, estimating the clock frequency drift based on the formula (3) when the PPP module cannot work normally, calculating the clock offset by using the estimated clock frequency drift, and generating the clock control quantity by using the clock offset. At this time, no long period error term is obtained, let wkThe value is 0.
And 7, when the PPP module returns to normal work, the PPP module continues to calculate the clock error so as to prevent the phenomenon that the fitting error causes the accumulation of the error of the receiver clock error.
The result of the clock fitting is updated every 6 hours by 8, and the clock control amount of the fitted clock model must be generated by the clock difference output from the PPP module.
And 9, when the time service receiver works for more than three days, on the basis of adopting the mode of the step 6, fitting a long-period error term caused by environmental factors through clock control quantity, and fitting the long-period error term in a polynomial mode in specific implementation.
In specific implementation, the automatic operation of the above processes can be realized by adopting a software technology.
The invention provides a clock combination disciplining method and a clock combination disciplining system of a GNSS time service receiver based on a PPP technology, which can also be used for testing and evaluating clock stability.
Claims (10)
1. A GNSS time service receiver clock combination regulation and control method based on PPP, the GNSS time service receiver includes PPP module, characterized by that: comprises a clock characteristic modeling stage and a clock regulation and control process,
a clock characteristic modeling process for modeling a clock characteristic when the PPP module is operating normally, comprising the steps of,
step SA1, regulating and controlling the clock according to the clock error estimated by the PPP module, and recording the clock error estimated by the PPP module of each epoch and the corresponding output clock control quantity;
step SA2, when the time service receiver works for more than a preset first time period, starting to perform clock characteristic modeling, and fitting clock frequency drift based on clock control quantity; when the time service receiver works for more than a preset second time period, modeling the long-period error item by using clock control quantity;
a clock regulation process for calculating a receiver clock difference through a clock characteristic modeling result when the PPP module cannot work normally, thereby continuing to regulate the clock, comprising the following steps,
step SB1, when the PPP module can not work normally, estimating the clock frequency deviation according to the fitted clock frequency drift and the long period error term, and estimating the clock error;
step SB2, calculating the clock control quantity according to the clock difference obtained in step SB 1;
at step SB3, the clock control amount calculated at step SB2 is rounded to an integer and sent to the clock as a final result.
2. The method of claim 1, wherein the method further comprises the steps of: step SA2, when the time service receiver works for more than a preset first time period, the clock characteristic modeling is started, and the implementation manner is as follows,
step SA2.1, preprocessing the recorded clock control quantity, and shaving out gross error data and divergence data;
step SA2.2, modeling the clock characteristics by the preprocessed clock control quantity, fitting by a linear function as follows, wherein the parameter to be fitted is clock frequency Drift,
wherein the content of the first and second substances,
indicating the amount of clock control applied to the clock at time k, t indicating the corresponding time value,
the initial value of the clock control amount is represented as the clock control amount corresponding to the nominal frequency of the clock, and m represents the scale factor of the clock control amount and is the frequency deviation corresponding to the minimum step of the control amount.
3. The method of claim 1, wherein the method further comprises the steps of: and when the time service receiver works for a second preset time period, modeling the long-period error term by using the clock control quantity, and realizing the modeling by adopting a polynomial fitting mode.
4. The method of claim 2, wherein the method further comprises the step of: the implementation of step SB1 includes the following steps,
step SB1.1, it is assumed that the PPP module cannot normally work after the moment k, and the clock frequency offset f at the moment is consideredkTo 0, the clock frequency offset f at time k +1 is calculatedk+1As follows below, the following description will be given,
fk+1＝fk+Drift×T+wk+1
wherein Drift is the frequency Drift of the fitting, T is the sampling interval, and wk+1Is a long period error term;
in step SB1.2, the clock offset is estimated as follows,
Tk+1＝Tk+(fk+1+fk)/2×T
wherein, Tk+1Receiver clock error, T, representing the estimate of time k +1kRepresenting the receiver clock difference at time k.
5. The method for GNSS time service receiver clock combination regulation and control based on PPP as claimed in claim 1, 2, 3 or 4, wherein: and step SB2, calculating the clock control quantity according to the clock difference obtained in the step SB1, and realizing the clock control quantity through a second-order phase-locked loop.
6. A GNSS time service receiver clock combination regulation and control system based on PPP, the GNSS time service receiver includes PPP module, its characterized in that: a clock characteristic modeling module and a clock regulation and control module are arranged,
a clock characteristic modeling module for modeling the clock characteristic when the PPP module is operating normally, including the following units,
a unit SA1, configured to regulate and control the clock according to the clock difference estimated by the PPP module, and record the clock difference estimated by the PPP module for each epoch and the corresponding output clock control amount;
a unit SA2, configured to start clock characteristic modeling after the time service receiver operates over a preset first time period, and fit a clock drift based on a clock control quantity; when the time service receiver works for more than a preset second time period, modeling the long-period error item by using clock control quantity;
the clock regulation and control module is used for calculating the clock difference of the receiver through the clock characteristic modeling result when the PPP module can not work normally so as to continuously regulate and control the clock and comprises the following units,
a unit SB1, configured to estimate, when the PPP module cannot normally operate, a clock frequency offset according to the fitted clock frequency drift and the long-period error term, and estimate a clock offset;
a unit SB2 for calculating the clock control quantity according to the clock difference obtained by the unit SB 1;
a unit SB3 for rounding the clock control amount calculated according to the unit SB2 to an integer and sending to the clock as a final result.
7. The system of claim 6, wherein the GNSS time service receiver clock combination regulation and control based on PPP comprises: the unit SA2 comprises the following sub-units,
the subunit SA2.1 is configured to perform preprocessing on the recorded clock control variable, and shave out gross error data and divergence data;
a subunit SA2.2 for modeling the clock characteristics with the preprocessed clocked quantities, comprising fitting with a linear function, the parameter to be fitted being the clock Drift,
wherein the content of the first and second substances,
indicating the amount of clock control applied to the clock at time k, t indicating the corresponding time value,
the initial value of the clock control quantity is represented as the clock control quantity corresponding to the nominal frequency of the clock, and m represents the scale factor of the clock control quantity.
8. The system of claim 6, wherein the GNSS time service receiver clock combination regulation and control based on PPP comprises: and when the time service receiver works for a second preset time period, modeling the long-period error term by using the clock control quantity, and realizing the modeling by adopting a polynomial fitting mode.
9. The system of claim 7, wherein the GNSS receiver clock combination regulation and control based on PPP is: the unit SB1 comprises the following sub-units,
a subunit SB1.1, configured to set that the PPP module cannot normally operate after time k, and consider that the clock frequency offset f at that timekTo 0, the clock frequency offset f at time k +1 is calculatedk+1As follows below, the following description will be given,
fk+1＝fk+Drift×T+wk+1
wherein Drift is the frequency Drift of the fitting, T is the sampling interval, and wk+1Is a long period error term;
subunit SB1.2, for clock offset estimation,
Tk+1＝Tk+(fk+1+fk)/2×T
wherein, Tk+1Receiver clock error, T, representing the estimate of time k +1kRepresenting the receiver clock difference at time k.
10. A GNSS time service receiver clock combination regulation and control system based on PPP as claimed in claim 6, 7, 8 or 9, characterized in that: the unit SB2 calculates the clock control quantity according to the clock difference obtained by the unit SB1, and the clock control quantity is realized through a second-order phase-locked loop.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101403790A (en) * | 2008-11-13 | 2009-04-08 | 浙江师范大学 | Accurate one-point positioning method for single-frequency GPS receiver |
| WO2009140768A1 (en) * | 2008-05-22 | 2009-11-26 | Novatel Inc. | Gnss receiver using signals of opportunity and assistance information to reduce the time to first fix |
| CN104102822A (en) * | 2014-07-01 | 2014-10-15 | 同济大学 | Method for modeling random characteristics of multi-frequency GNSS (global navigation satellite system) observed values |
| JP5730064B2 (en) * | 2011-02-22 | 2015-06-03 | 日本無線株式会社 | Frequency tracking device |
| CN107678048A (en) * | 2017-10-10 | 2018-02-09 | 唐山学院 | Method is pre-selected in the ultrafast clock correction forecasting model of satellite clock |
| CN108490463A (en) * | 2018-02-09 | 2018-09-04 | 东南大学 | Clock correction estimation of deviation and modeling method between a kind of big-dipper satellite frequency |
| CN108732597A (en) * | 2018-06-04 | 2018-11-02 | 北京未来导航科技有限公司 | A kind of the time reference method for building up and system of multi-satellite navigation system |
-
2019
- 2019-02-27 CN CN201910146620.9A patent/CN109870898B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009140768A1 (en) * | 2008-05-22 | 2009-11-26 | Novatel Inc. | Gnss receiver using signals of opportunity and assistance information to reduce the time to first fix |
| CN101403790A (en) * | 2008-11-13 | 2009-04-08 | 浙江师范大学 | Accurate one-point positioning method for single-frequency GPS receiver |
| JP5730064B2 (en) * | 2011-02-22 | 2015-06-03 | 日本無線株式会社 | Frequency tracking device |
| CN104102822A (en) * | 2014-07-01 | 2014-10-15 | 同济大学 | Method for modeling random characteristics of multi-frequency GNSS (global navigation satellite system) observed values |
| CN107678048A (en) * | 2017-10-10 | 2018-02-09 | 唐山学院 | Method is pre-selected in the ultrafast clock correction forecasting model of satellite clock |
| CN108490463A (en) * | 2018-02-09 | 2018-09-04 | 东南大学 | Clock correction estimation of deviation and modeling method between a kind of big-dipper satellite frequency |
| CN108732597A (en) * | 2018-06-04 | 2018-11-02 | 北京未来导航科技有限公司 | A kind of the time reference method for building up and system of multi-satellite navigation system |
Non-Patent Citations (2)
| Title |
|---|
| Maintaining real-time precise point positioning during outages of orbit and clock corrections;Ahmed El-Mowafy.et.al;《GPS Solutions》;20171231;全文 * |
| 北斗卫星导航系统的精密定轨与定位研究;施闯等;《中国科学》;20120531;全文 * |
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