CN102854515A - Method for calibrating combination zero value under constellation positioning mode - Google Patents
Method for calibrating combination zero value under constellation positioning mode Download PDFInfo
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- CN102854515A CN102854515A CN201210095989XA CN201210095989A CN102854515A CN 102854515 A CN102854515 A CN 102854515A CN 201210095989X A CN201210095989X A CN 201210095989XA CN 201210095989 A CN201210095989 A CN 201210095989A CN 102854515 A CN102854515 A CN 102854515A
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Abstract
The invention discloses a method for calibrating a combination zero value under a constellation positioning mode. On the basis of separately calibrating range aero values and time difference zero values traditionally, a novel calibrating method, namely the method for calibrating the combination zero value, is provided. According to the method for calibrating the combination zero value, any complicated ground auxiliary devices are not required, the method can be performed in wired and wireless states, the range and time difference zero values can be calibrated once by the method, the examination for calibration accuracy is facilitated, the calibration accuracy is high, by means of the simple calibrating method, the complexity of the calibration is greatly reduced, the efficiency is improved, the method is suitable for the zero value calibration of two satellites, the zero value calibration for a plurality of satellites is also simple and practical, the zero values of the plurality of satellites can be simultaneously calibrated, and thereby the method is practical and effective.
Description
Technical field
The present invention relates to demarcate under a kind of constellation station-keeping mode the method for combination null value, belong to formation flight device technical field.
Background technology
Flight formation constellation pattern is a kind of novel space networking model, adopt inter-satellite link to carry out intersatellite communication, not only be conducive to improve the constellation operation performance, enlarge constellation detection covering spatial domain scope, but also the scale that is conducive to dwindle ground support system, observing and controlling and the number of greatly having simplified ground system pass management.And the positional precision of Satellite Formation Flying and time difference precision will be the keys that guarantees the constellation bearing accuracy.
The constellation pattern is a kind of novel pattern, how to realize that in space industry the null value under the constellation pattern is demarcated, and data is less at home, also rarely reports abroad.Existing system zero-range set constant scaling method all is that traditional star ground observing and controlling answering machine and ground control station system are demarcated, and the method is not suitable for the constellation pattern, in order to guarantee time synchronized, requires to demarcate zero-range set constant and time difference null value under the constellation pattern.
Summary of the invention
Technology of the present invention is dealt with problems and is: overcome the deficiencies in the prior art, proposed to demarcate under a kind of constellation station-keeping mode the method for combination null value, the method is not limited to an inter-satellite link, many inter-satellite link also can be demarcated simultaneously, satellite to formation flight, greatly reduce engineering difficulty and complicacy, and stated accuracy is very high, reaches nanosecond.
Technical scheme of the present invention is:
Demarcate the method for combination null value under a kind of constellation station-keeping mode, rely on the first satellite, the realization of the second satellite sum counter, step is as follows:
Demarcate the method for combination null value under a kind of constellation station-keeping mode, rely on the first satellite, the second satellite, the realization of vector network analyzer sum counter, step is as follows:
(1) first satellite and the second satellite are set to constellation ray mode, namely on the ground the first satellite and the second passing of satelline cable are linked together, the path that forms between the receiver of the transmitter of the first satellite and the second satellite is forward link, and the path that forms between the receiver of the transmitter of the second satellite and the first satellite is reverse link;
(2) first satellites and the second satellite all are connected to counter by cable;
(3) by the time delay τ of vector network analyzer to described forward link cable
AbTime delay τ with the reverse link cable
BaDemarcate;
(4) time difference Δ t by counter measures the first satellite and the second satellite;
(5) by formula T
1=τ
a'+τ
Ba+ τ
b+ Δ t and T
2=τ
b'+τ
Ab+ τ
a-Δ t calculates respectively forward direction pseudorange T
1With reverse pseudorange T
2, wherein, T
1Be the forward direction pseudorange, i.e. the time difference of the local clock time signal of the first satellite and the time signal of the second satellite of receiving; T
2Be reverse pseudorange, i.e. the time difference of the local clock time signal of the second satellite and the time signal of the first satellite of receiving; τ
a, τ '
aBe respectively the time delay of the first satellite transmitter and receiver; τ
b, τ '
bBe respectively the time delay of the second satellite transmitter and receiver;
(6) by formula Z
1=T
1-τ
Ba-Δ t and Z
2=T
2-τ
Ab+ Δ t calculates respectively forward direction null value Z
1With reverse null value Z
2
(7) pass through formula
With
Calculate respectively chain-circuit time delay theoretical value R and time difference theoretical value Δ t ';
(8) judge τ
AbWhether=R and Δ t=Δ t ' all set up, if all set up, the demarcation of then making up null value is effective; Otherwise return step (3) from newly carrying out.
The cable length of the cable length of forward link and reverse link is identical in the described step (1), and to be connected to the cable length of counter identical with the cable length that the second satellite is connected to counter for the first satellite in the step (2).
Invention advantage compared with prior art is:
(1) the constellation pattern is different from the star ground mode, after in case constellation is determined, the unique characteristic of inter-satellite link combination null value will be arranged, and the present invention has avoided the combination null value of single satellite is demarcated, and has realized the combination null value of inter-satellite link is carried out disposable demarcation.
(2) by measuring forward direction null value and reverse null value, one-time calculation goes out to make up null value, need not the zero-range set constant between star and time difference null value are demarcated separately, this is so that the constellation pattern, especially more to satellite constellation pattern, simplify greatly the complicacy that null value is demarcated, reduced the difficulty of demarcating.
(3) after null value carries out upper notes to combination, the carrying out that only needs to measure the time difference between counter and star directly relatively can draw the accuracy of demarcation, equally, the distance of measuring between the distance of cable between star and star compared get final product to get the accuracy of zero-range set constant, do not need to carry out other any complex calculation, so also that dropping to of systematic error is minimum.
(4) can there be the ray mode subscript fixed, also can under wireless mode, demarcate, wireless mode is final state, can will there be ray mode to demarcate as the basis, then after delay testing being carried out in space and antenna etc., be fitted to wired the inside and go, compare with wireless direct test, eliminate the error of test, improved accuracy.
Description of drawings
Fig. 1 interstellar distance and the time difference get the measuring principle synoptic diagram;
The wireline equipment of the constellation pattern that two satellites of Fig. 2 form connects block diagram;
Wireline equipment null value under the constellation pattern that two satellites of Fig. 3 form is demarcated and is connected block diagram;
Fig. 4 is process flow diagram of the present invention.
Embodiment
We introduce the measuring principle of interstellar distance and the time difference first, such as Fig. 2, shown in Figure 3, the satellite of formate all has rubidium clock and time management unit, time management unit output pulse per second (PPS) (1pps), the output 10MHz of time management unit is the reference frequency of each equipment of system, and the time difference of the first satellite (A star) and the second satellite (B star) is defined as the time difference between the satellite time administrative unit output pulse per second (PPS) forward position of two stars.Signal adopts two-way pseudo-code ranging technology between star, utilizes the observing and controlling spreading code as ranging code, utilizes two dimensional method to resolve interstellar distance and clock correction.Pseudo-random code ranging not only has very high distance accuracy, because its continuity can be guaranteed the real-time of finding range and in real time smoothing processing calculating be carried out in the original observed quantity of finding range.
The ultimate principle of two dimensional method utilizes respectively equipment transmission separately fixed for A star and the B star of participating in comparison
The time signal, and receive timing signal from the other side.
As shown in Figure 4, the invention provides the method for demarcating the combination null value under a kind of constellation station-keeping mode, rely on the first satellite, the realization of the second satellite sum counter, step is as follows:
(1) first satellite and the second satellite are set to constellation ray mode, namely on the ground the first satellite and the second passing of satelline cable are linked together, the path that forms between the receiver of the transmitter of the first satellite and the second satellite is forward link, and the path that forms between the receiver of the transmitter of the second satellite and the first satellite is reverse link; The cable length of forward link is identical with the cable length of reverse link,
(2) first satellites and the second satellite all are connected to counter by cable; The cable length that the first satellite is connected to counter is identical with the cable length that the second satellite is connected to counter;
The time difference of as shown in Figure 1, establishing the B star timing signal of local clock timing signal that the A star measures and reception is T
1, the time difference of the local clock timing signal that the B star is measured and the A star timing signal of reception is T
2, T
1And T
2Be respectively forward direction pseudorange and reverse pseudorange, the time difference (clock correction) of A star and B star two places clock is Δ t, can draw:
T
1＝τ
a′+τ
ba+τ
b+Δt (1)
T
2＝τ
b′+τ
ab+τ
a-Δt (2)
In the formula, τ
a, τ '
a-----is respectively the time delay of A star transmitter (transmitter) and receiving equipment (receiver);
τ
b, τ '
b-----is respectively the time delay of B star transmitter (transmitter) and receiving equipment (receiver);
τ
Ab-----represents during wired connection to be represented during wireless connections by the propagation delay of A star emitting antenna to B star receiving antenna by A star transmitter and time delay to the wired connection of B star receiving equipment;
τ
Ba-----represents during wired connection to be represented during wireless connections by the propagation delay of B star emitting antenna to A star receiving antenna by B star transmitter and time delay to the wired connection of A star receiving equipment;
T
1The local clock time signal that-----A star is measured and the time difference that receives B star time signal;
T
2The local clock time signal that-----B star is measured and the time difference that receives A star time signal.Got by formula (1)-(2)
T
1-T
2＝2Δt+(τ
b-τ
a)+(τ
a′-τ
b′)+(τ
ba-τ
ab) (3)
Δt＝[(T
1-T
2)+(τ
a-τ
b)+(τ
b′-τ
a′)+(τ
ab-τ
ba)]/2 (4)
Completing steps (2) afterwards, next step is:
(3) by the time delay τ of vector network analyzer to described forward link cable
AbTime delay τ with the reverse link cable
BaDemarcate; Because the length of forward link cable is identical with the length of reverse link cable, therefore, τ
AbAlmost with τ
BaEquate that error can be ignored;
(4) time difference Δ t by counter measures the first satellite and the second satellite;
(5) by formula T
1=τ
a'+τ
Ba+ τ
b+ Δ T and T
2=τ
b'+τ
Ab+ τ
a-Δ t calculates respectively forward direction pseudorange T
1With reverse pseudorange T
2, wherein, t
1Be the forward direction pseudorange, i.e. the time difference of the local clock time signal of the first satellite and the time signal of the second satellite of receiving; t
2Be reverse pseudorange, i.e. the time difference of the local clock time signal of the second satellite and the time signal of the first satellite of receiving; τ
a, τ '
aBe respectively the time delay of the first satellite transmitter and receiver; τ
b, τ '
bBe respectively the time delay of the second satellite transmitter and receiver;
When A star and B star are launched timing signal at synchronization, because through identical wired apart from length or identical spatial path, because the travel-time approaches, signal frequency approaches, its difference is very little, can approximately equal, i.e. τ
Ab=τ
Ba, then have:
Δt′＝[(T
1-T
2)+(τ
a-τ
b)+(τ
b′-τ
a′)]/2 (5)
Δ t ' is time difference theoretical value, in fact when having relative radial motion between the satellite, and τ
Ab≈ τ
BaWhen the timing signal on two satellites can be adjusted to the degree that relatively approaches simultaneously, error can be ignored.After the two-way link between star is set up, carry out first time comparison, to carry out markers with the clock correction measured value of gained and adjust as initial presynchronization, the clock correction measuring accuracy of carrying out after the presynchronization can satisfy accuracy requirement.Chain-circuit time delay theoretical value R (interstellar distance) can draw:
By as can be known top, the distance that whole inter-satellite link will be demarcated and time difference null value are exactly to be the time delay combinations of on-board equipment (τ
a-τ
b)+(τ '
b-τ '
a), (τ
a+ τ
b+ τ
a'+τ
b') can be effectively and Accurate Measurement, namely can draw the exact value of interstellar distance and the time difference, but inter-satellite link equipment carries out each equipment segmentation demarcation sneaks into various errors easily, and some can't directly be measured, therefore this paper has provided a kind of combination null value scaling method, namely directly mark the combination null value of interstellar distance null value and time difference null value by computing, we claim to make up null value is forward direction null value and reverse null value, and the null value of not adjusting the distance respectively and time difference null value are carried out independent calibration.
Result above analyzing can find out, we with the A star to the combination null value of B star forward direction null value Z
1, the B star to the combination null value of A star reverse null value Z
2, we can derive from top formula:
Z
1＝τ
b+τ
a′＝T
1-τ
ba-Δt (7)
Z
2＝τ
a+τ
b′＝T
2-τ
ab+Δt (8)
In the formula, Z
1-----A star to the combination null value of B star the forward direction null value;
Z
2-----B star to the combination null value of A star reverse null value;
τ
Ab-----is by the propagation delay of A star to the B star, with τ
BaEquate, known;
τ
Ba-----is by the propagation delay of B star to the A star, with τ
AbEquate; Known
Δ t-----is the real-time time difference between star, and instrument can directly record, and is known;
T
1-----is identical with the front definition, is known parameters here;
T
2-----is identical with the front definition, is known parameters here.
Can be found out forward direction combination null value Z1 and reverse combination null value Z by top result
2Can be by the pseudorange T of two stars measurements
1And T
2, calculate acquisition by remote measurement or floor treatment instrument; Interstellar distance τ
Ab, τ
BaCan shift to an earlier date the passage vector network analyzer and demarcate propagation delay time, and both equate; Real-time clock correction Δ t between the A that the high precision technology device can directly be measured, the B, then utilize formula (7), (8) directly to obtain its combination null value, need not demarcate respectively time difference null value and zero-range set constant respectively, the complicacy of the calibration of greatly simplifying, this scaling method are a kind of new method that null value is demarcated.
The below is that the step (5) that sums up calculates pseudorange step afterwards:
(6) pseudorange that calculates according to preceding step, the time difference and cable time delay are passed through formula
Z
1=τ
b+ τ
a'=T
1-τ
Ba-Δ t and Z
2=τ
a+ τ
b'=T
2-τ
Ab+ Δ t calculates respectively forward direction null value Z
1With reverse null value Z
2
(7) T in formula
1=τ
a'+τ
Ba+ τ
b+ Δ t and R
2=τ
b'+τ
Ab+ τ
aDeduct combination null value Z among the-Δ t
1And Z
2, forward direction and reverse combination null value have obtained counteracting like this, obtain T
1'=T
1-Z
1=τ
Ba+ Δ t and T
2'=T
2-Z
2=τ
Ab-Δ t is like this through top two formula additions and subtract each other and can derive
Therefore, this step is and passes through formula
With
Calculate respectively chain-circuit time delay theoretical value R and time difference theoretical value Δ t ';
(8) with the calibrated inter-satellite link null value Z of system
1And Z
2After carrying out upper notes, judge the relatively τ of vector network analyzer demarcation
AbWhether (obtaining in the step (3)) equates with chain-circuit time delay theoretical value R, judges simultaneously whether the Δ t (obtaining in the step (4)) of counter measures equates with time difference theoretical value Δ t ', if equate that all the demarcation of then making up null value is effective; Otherwise return step (3) from newly carrying out.
Can demarcate other inter-satellite link states with the inventive method, the method for demarcation is the same; For the multi-satellite inter-satellite link, also can utilize top mode to demarcate.Therefore said method is actual is a kind of general null value combination standardization, can effectively verify the null value validity of inter-satellite link.
Other contents that are not described in detail belong to this area professional and technical personnel's known technology in the instructions of the present invention.
Claims (3)
1. demarcate the method that makes up null value under a constellation station-keeping mode, rely on the first satellite, the second satellite, the realization of vector network analyzer sum counter, it is characterized in that step is as follows:
(1) first satellite and the second satellite are set to constellation ray mode, namely on the ground the first satellite and the second passing of satelline cable are linked together, the path that forms between the receiver of the transmitter of the first satellite and the second satellite is forward link, and the path that forms between the receiver of the transmitter of the second satellite and the first satellite is reverse link;
(2) first satellites and the second satellite all are connected to counter by cable;
(3) by the time delay τ of vector network analyzer to described forward link cable
AbTime delay τ with the reverse link cable
BaDemarcate;
(4) time difference Δ t by counter measures the first satellite and the second satellite;
(5) by formula T
1=τ
a'+τ
Ba+ τ
b+ Δ t and T
2=τ
b'+τ
Ab+ τ
a-Δ t calculates respectively forward direction pseudorange T
1With reverse pseudorange T
2, wherein, T
1Be the forward direction pseudorange, i.e. the time difference of the local clock time signal of the first satellite and the time signal of the second satellite of receiving; T
2Be reverse pseudorange, i.e. the time difference of the local clock time signal of the second satellite and the time signal of the first satellite of receiving; τ
a, τ '
aBe respectively the time delay of the first satellite transmitter and receiver; τ
b, τ '
bBe respectively the time delay of the second satellite transmitter and receiver;
(6) by formula Z
1=T
1-τ
Ba-Δ t and Z
2=T
2-τ
Ab+ Δ t calculates respectively forward direction null value Z
1With reverse null value Z
2
(7) pass through formula
With
Calculate respectively chain-circuit time delay theoretical value R and time difference theoretical value Δ t ';
(8) judge τ
AbWhether=R and Δ t=Δ t ' all set up, if all set up, the demarcation of then making up null value is effective; Otherwise return step (3) from newly carrying out.
2. demarcate the method for combination null value under a kind of constellation station-keeping mode according to claim 1, it is characterized in that: the cable length of the cable length of forward link and reverse link is identical in the described step (1).
3. demarcate the method for combination null value under a kind of constellation station-keeping mode according to claim 1, it is characterized in that: to be connected to the cable length of counter identical with the cable length that the second satellite is connected to counter for the first satellite in the step (2).
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| CN103217689A (en) * | 2013-03-29 | 2013-07-24 | 航天东方红卫星有限公司 | PPS (pulse per second) synchronizing method under constellation mode |
| CN104333408A (en) * | 2014-09-26 | 2015-02-04 | 航天东方红卫星有限公司 | Inter-satellite communication system used for realizing high-dynamic and low-delay space teleoperation |
| CN104618088A (en) * | 2014-10-16 | 2015-05-13 | 烟台三航雷达服务技术研究所有限公司 | ADS-B (Automatic Dependent Surveillance-Broadcast) signal based wide-area multi-station time synchronizing method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103217689A (en) * | 2013-03-29 | 2013-07-24 | 航天东方红卫星有限公司 | PPS (pulse per second) synchronizing method under constellation mode |
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| CN104333408A (en) * | 2014-09-26 | 2015-02-04 | 航天东方红卫星有限公司 | Inter-satellite communication system used for realizing high-dynamic and low-delay space teleoperation |
| CN104333408B (en) * | 2014-09-26 | 2017-09-29 | 航天东方红卫星有限公司 | A kind of Inter-satellite Communication System for being used to realize high dynamic and low time delay Space teleoperation |
| CN104618088A (en) * | 2014-10-16 | 2015-05-13 | 烟台三航雷达服务技术研究所有限公司 | ADS-B (Automatic Dependent Surveillance-Broadcast) signal based wide-area multi-station time synchronizing method |
| CN104618088B (en) * | 2014-10-16 | 2018-05-08 | 烟台三航雷达服务技术研究所有限公司 | Wide area multistation method for synchronizing time based on ADS-B signals |
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Application publication date: 20130102 |