CN106403960B - A kind of constellation navigation method suitable for self-organizing constellation - Google Patents
A kind of constellation navigation method suitable for self-organizing constellation Download PDFInfo
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- CN106403960B CN106403960B CN201610846329.9A CN201610846329A CN106403960B CN 106403960 B CN106403960 B CN 106403960B CN 201610846329 A CN201610846329 A CN 201610846329A CN 106403960 B CN106403960 B CN 106403960B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
- G01C21/24—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 specially adapted for cosmonautical navigation
Abstract
The invention discloses a kind of constellation navigation methods suitable for self-organizing constellation, belong to the technical field of constellation navigation.Aiming at the problem that communication between self-organizing constellation can not uninterruptedly implement star during satellite transit, utilize the Cross-Link measurement information fusion technology of single star independent navigation in constellation and discontinuity, independent navigation is carried out to self-organizing constellation, improve the navigation accuracy of constellation, reduce the calculation amount in navigation procedure, solves the limitation problem that navigates caused by self-organizing constellation is irregularly constrained by satellite orbit.
Description
Technical field
The invention discloses a kind of constellation navigation methods suitable for self-organizing constellation, belong to the technology neck of constellation navigation
Domain.
Background technique
The concept of self-organizing constellation is proposed relative to conventional satellite constellation.Conventional satellite constellation is usually by carrier rocket
Each satellite in constellation is sent to predetermined position.Therefore, transmitting conventional satellite constellation needs dedicated carrier rocket, and expense is high
It is expensive.The deployment of self-organizing constellation does not use dedicated carrier rocket, but uses and the modes such as carry and be sent to satellite and main task
The similar track of satellite, to constitute constellation.
The measuring device that the independent navigation research of satellite is only relied under conditions of not depending on earth station on satellite is true in real time
Determine position and speed, the in-orbit completion aerial mission of satellite.According to the difference of used sensor and metrical information, satellite is certainly
Main navigation means are also different, have at present using more autonomous navigation of satellite technology sensitive based on magnetometer, radar altimeter, star
The autonomous navigation technology of device, ultraviolet sensors, GPS etc..
Current constellation independent navigation research is to study star based on conventional constellation configuration on the basis of single star independent navigation
The technologies such as bidirectional ranging, data exchange and processing between the star of seat.Self-organizing constellation Satellite must adapt to the launching condition of primary
And running track, the track irregularity of constellation satellite, so that there are unstability for the configuration of self-organizing constellation, for regular tradition
The methods of the H_2O maser of constellation and data communication can not uninterruptedly be implemented during self-organizing constellation Satellite is run.
Research shows that it is not enough to maintain the performance requirement of self-organizing constellation merely with single star independent navigation, and self-organizing constellation
Track particularity do not allow to implement continual star to entire constellation again communication link.For this problem, the application purport
Iing is proposed a kind of navigation side that can adapt to self-organizing constellation navigation accuracy requirement and can be realized entire constellation uninterrupted communication
Method.
Summary of the invention
Goal of the invention of the invention is the deficiency for above-mentioned background technique, is provided a kind of suitable for self-organizing constellation
Constellation navigation method realizes self-organizing constellation navigation and improves navigation accuracy, solves self-organizing constellation by satellite orbit
The technical issues of irregular constraint.
The present invention adopts the following technical scheme that for achieving the above object
A kind of constellation navigation method suitable for self-organizing constellation, includes the following steps:
A, the constellation period of self-organizing constellation is calculated according to the running track of each satellite；
B, single star navigation is carried out to every satellite；
C, according to every satellite and its with visible star apart from it is nearest at the time of to the entire constellation period carry out node division simultaneously
Each node is marked, each satellite is arranged according to the number of the visible star of satellite, using the visible least satellite of star number mesh between first order star
Telecommunication satellite, the satellite minimum with telecommunication satellite visible frequencies between upper level star according to preferential selection are communicated as between next stage star
The principle of satellite is that the moment is communicated between communications satellite and star between every satellite and its visible satellite selection star, wherein
Use the Dynamic Programming Idea of operational research communications satellite and star between every satellite and its visible satellite selection star
Between communicate the moment, specifically: telecommunication satellite is each to construct communication loop between star between choosing stars at different levels since first order satellite
The communication moment of communications satellite communications satellite and upper level star between current level star between communications satellite and upper level star between grade star
Between communications satellite for the first time apart from it is nearest at the time of, when between junior's star between communications satellite and higher level's star communications satellite repeat or have more
Between a star when communication loop, chooses the satellite low with telecommunication satellite visible frequencies between upper level star time and communicated as between next stage star
Satellite；
D, in satellite transit, communications satellite transmits Cross-Link measurement information and Dan Xing between communicating moment Shi Yuqi star between star
Navigation information；
E, all Cross-Link measurement information and single star navigation information of the entire constellation of fusion treatment.
Scheme, basis described in step A are advanced optimized as the constellation navigation method suitable for self-organizing constellation
The running track of each satellite calculates the constellation period of self-organizing constellation, method particularly includes: observation satellite running track will have
The satellite of identical or very much like running track is divided into one group and each satellite in every group of satellite is marked, with each group
The least common multiple of period of satellite is the constellation period of self-organizing constellation.
Further, the constellation navigation method suitable for self-organizing constellation, step B uses the magnetic based on magnetometer
Air navigation aid carries out single star navigation to every satellite, and filtering mode is realized by adaptive extended kalman filtering algorithm, in real time
Estimate variance are as follows:Wherein, k indicates the measurement moment, and k is long by sliding data window
Spend W measurement, dkThe difference for the observation that be k moment filter actual observed value and k-1 moment predict the k moment, i=k-W+1, di
The difference for the observation that be i moment filter actual observed value and i-1 moment predict the i moment,Respectively slide number
According to length of window be k-1, k when estimate variance.
Scheme is advanced optimized as the constellation navigation method suitable for self-organizing constellation, described in step D
Cross-Link measurement information includes distance measure and clock deviation measured value.
As the scheme that advanced optimizes of the constellation navigation method suitable for self-organizing constellation, step E is using adaptive
Answer all Cross-Link measurement information and single star navigation information of the entire constellation of expanded Kalman filtration algorithm fusion treatment.
The present invention by adopting the above technical scheme, has the advantages that
(1) it is navigated using the magnetic navigation technology based on magnetometer to satellite, using adaptive extended kalman filtering
Mode improves the navigation accuracy of satellite；
(2) selection and survey at Cross-Link measurement moment are carried out to the satellite in constellation using the thoery of dynamic programming in operational research
Measure information satellite selection, have effect once and for all, while every satellite completes itself independent navigation, by phased manner into
DATA REASONING and information exchange between planet overcome the irregular obstacle of self-organizing constellation satellite orbit；
(3) present invention improves navigation accuracy, reduces overall navigation calculating while realizing self-organizing constellation navigation
Amount, provides good guarantee for self-organizing constellation runnability.
Detailed description of the invention
Fig. 1 is flow chart of the present invention.
Fig. 2 is the navigation mode of single star navigation.
Fig. 3 is the satellite sequence choosing method of H_2O maser.
Specific embodiment
The technical solution of invention is described in detail with reference to the accompanying drawing.
Since there are unstability, H_2O maser and data communication for traditional rule constellation etc. for self-organizing constellation configuration
Method can not uninterruptedly be implemented during self-organizing constellation Satellite is run.To solve the above-mentioned problems, the present invention proposes
The scheme of " single star independent navigation+discontinuity Cross-Link measurement information fusion technology " carries out independent navigation to self-organizing constellation.Using
Magnetic navigation method based on magnetometer carries out autonomous orbit determination to single star；Cross-Link measurement data are selected by way of Dynamic Programming
At the time of satellite and discontinuity metrical information；Navigation information and Cross-Link measurement letter are merged using expanded Kalman filtration algorithm
Breath realizes the long-term autonomous navigation of self-organizing constellation.
A kind of constellation navigation method suitable for self-organizing constellation proposed in this paper, as shown in Figure 1, steps are as follows:
(1) running track of observation satellite, according to the orbital period of satellite and running track to the satellite in constellation into
Line flag marks the satellite in self-organizing constellation to be respectively as follows:
A1,A2,…An；B1,B2,…；C1...,
Wherein, satellite x1,x2,…xnThere is an identical or very much like running track, x A, B, C ...,
The period size of self-organizing constellation Satellite is calculated, using the least common multiple period of all period of satellite as
In the constellation period of self-organizing constellation, it is denoted as T.
(2) single star navigation, filtering mode are carried out using the magnetic navigation method based on magnetometer to every satellite in constellation
For adaptive extended kalman filtering (adaptive EKF algorithm), the process of entire single star navigation as shown in Fig. 2,
The track equation of motion of satellite are as follows:
In formula: LeiFor state vector, Lei=[x, y, z, vx,vy,vz]T, x, y, z, vx,vy,vzRespectively satellite is in x, y, z
The position and speed in three directions, μ are Gravitational coefficient of the Earth, μ=3.986 × 1014m3/s2；J2For the humorous item of terrestrial gravitation second order band
Coefficient, J2=1.08263 × 10-3, r is the earth's core away from ReIt is the earth with reference to equatorial radius, w is equivalent random white noise,
The measurement equation of magnetometer orbit determination are as follows:
In formula: V be earth's magnetic field potential function, r be the earth's core away from, φ is geographic logitude, and θ is geocentric colatitude,For
Reduced latitude, ZBFor absolute force Vector Mode, Bx、By、BzFor the magnetic intensity vector in three directions of x, y, z, vBFor earth magnetism reference
Noise is measured caused by remanent magnetism interference etc. in field model error and magnetometer survey error, celestial body.
In adaptive filter algorithm, real-time estimation varianceIt is calculated by following formula:
In formula, k indicates measurement moment, dkIt is k moment filter actual observed value ZkThe sight that the k moment is predicted with the k-1 moment
Measured valueDifference, i=k-W+1, diThe observation that be i moment filter actual observed value and i-1 moment predict the i moment it
Difference,Estimate variance when respectively sliding data window length is k-1, k, k pass through sliding data window W length degree
It measures, W is selected in actual dynamic range according to system sensitivity and accuracy in experiment.In addition, in adaptive algorithm,
The residual variance at k momentEstimated valueAre as follows:RkFor the observation noise variance matrix at k moment, the k+1 moment
Observation noise variance matrix Rk+1Estimated valueAre as follows:The system noise variance matrix Q at k momentk's
Estimated valueAre as follows:Wherein, Pk+1|kFor optimum prediction valuation error covariance matrix, Pk|kFor optimal filter error covariance matrix,
Φk+1|kFor state vector X (the state vector L as in the track equation of motion of satelliteei) from the k moment it is transferred to the k+1 moment
State-transition matrix, Rk+1For the observation noise variance matrix at k+1 moment, QkFor the system noise variance matrix at k moment, Hk+1For k+1
Moment measurement vector Zk+1With state vector Xk+1Between observed differential matrix.
(3) communicated the selection and star of communications satellite carrying out star to each satellite and its visible satellite when
Dynamic Programming Idea of the selection mode at quarter by operational research, specific steps are as follows:
1) according to every satellite and its with visible star apart from it is nearest at the time of to the entire constellation period carry out node division, and
Carry out node time instance mark；
2) select the satellite of visible star minimal number in the process of running for first satellite, according to the visible star number of satellite
The how many pair satellites of purpose arrange；
3) from first satellite, choosing the minimum satellite of visible frequencies therewith is second satellite, the of same period
One distance most in short-term carve be information measurement exchange the moment, and so on, rear stage choose satellite can not with it is preceding what choose
Satellite repeats；
4) if the satellite that back rank is chosen is contradicted with the satellite that front rank is chosen, the upper level from contradiction is other
Start to be adjusted, the rudimentary satellite of its visible frequencies time is not chosen to the upper level at contradiction, and repeat step 3), until institute
The satellite of the afterbody of choosing and first satellite can carry out H_2O maser and data exchange, constitute a loop；
5) in each constellation cycle T, have and only once communication loop, it is such as contradictory, it repeats step 4) and is adjusted；
It is as shown in Figure 3 to choose process, it is assumed that the satellite of first selection is A, and the visible star in operational process is B, C,
And the visible frequencies of A star and B star then select B star and A star to carry out information lower than the visible frequencies with C star in a constellation period
Measurement, and so on.
(4) in self-organizing constellation, the relative positional relationship between satellite is usually with time change, in the constellation period
Interior distribution timing node come carry out between star information measurement with communicate, i.e., in satellite transit to the particular moment pair in each constellation period
Its visible satellite chosen carries out the transmission of the Cross-Link measurement information and information of discontinuity.Distribute to every satellite 1.5s when
Between interval be used for H_2O maser or communication, using the shortest preceding 0.5s of the satellite distance-measuring satellite linear distance selected with it as satellite
The initial time of ranging communication.It is irregular based on self-organizing constellation satellite orbit, lateral link is used when every two satellite communications
Communication.The Cross-Link measurement information carried out between satellite includes distance measure and clock deviation measured value, the transmission of information include away from
From information, the orbit information of clock deviation information and single star navigation, while distance and clock deviation parameter are realized using bidirectional ranging between star
Decoupling, with this in constellation navigation satellite realize time synchronization.
(5) measurement data is handled, single star is carried out from the Cross-Link measurement information for organizing navigation information and discontinuity to entire constellation
Fusion handles fuse information, completes constellation navigation.Every satellite only handles measurement data relevant to oneself, updates oneself
Track, clock deviation and navigational parameter.Cross-Link measurement information amalgamation mode is the adaptive EKF algorithm merged based on information, design
Overall situation estimation and subfilter estimation carry out information distribution,
Global best estimates:
By the filtering processing of decentralized concurrent operation, obtained n partial estimation value χ1(t),χ2(t)…χn(t) and estimate
Counting error is respectively P1(t),P2(t)…Pn(t), it is merged as the following formula in senior filter, obtains global estimated value:
Global estimated result is fed back into subfilter, as k moment subfilter estimated value:
In formula, i=1,2 ..., n, β1(k)+β2(k)+…βi(k)…+βn(k)=1,0≤βi(k)≤1, QgFor system
The variance matrix of state-noise, the factor of i-th of subfilter of k moment are as follows:
In formula, | | | |FFor Frobenius norm, i.e., have to Arbitrary Matrix A:
Information fusion observation updates:
EKF algorithm is carried out to subfilter according to new observation information, steps are as follows for specific algorithm:
K (k)=P (k, k-1) HT(k)×[H(k)P(k,k-1)HT(k)+R(k)]-1,
P (k)=[I-K (k) H (k)] P (k, k-1) [I-K (k) H (k)]T+K(k)R(k)KT(k),
Wherein,PgIt (k) is the global estimated value at k moment, global evaluated error, P1(k),P2(k)…Pn(k) it is
The evaluated error of the 1st to the n-th subfilter of k moment, χ1(k),χ2(k)…χnIt (k) is the 1st to n-th subfilter of k moment
Partial estimation value,For the partial estimation value of i-th of subfilter, Pi(k)、QiIt (k) is respectively i-th of subfilter of k moment
Evaluated error, to the estimated value of system mode noise variance matrix, Pg(k)、Qg(k) it is respectively the global evaluated error at k moment, is
The variance matrix of system state-noise, βiIt (k) is the factor of i-th of subfilter of current time, PiIt (k-1) is i-th of son of k-1 moment
The evaluated error of filter,The respectively state vector estimated value at k-1 moment, k moment,
For the k moment state vector that the k-1 moment is estimated, f () is state vector estimation function, and t is continuous time, and T is self-organizing
The constellation period of constellation, K (k) are the calculating formula that filter observes the moment, and z (k) is the observation of k moment filter, h
() is the expression formula for calculating prediction observation, and P (k, k-1) is optimum prediction valuation error covariance matrix, when H (k) is k
Carve measurement vector ZkWith state vector XkBetween observed differential matrix, R (k) be the k moment observation noise variance matrix, P (k) be k when
Carve evaluated error.
In conclusion the present invention navigates to satellite using the magnetic navigation technology based on magnetometer, satellite is improved
Navigation accuracy carries out the selection and measurement at Cross-Link measurement moment using the thoery of dynamic programming in operational research to the satellite in constellation
The selection of information satellite has effect once and for all, while every satellite completes itself independent navigation, carries out by phased manner
DATA REASONING and information exchange between star overcome the irregular obstacle of self-organizing constellation satellite orbit, realize self-organizing constellation
Navigation, and improve navigation accuracy, reduce overall navigation calculation amount, good guarantor is provided for self-organizing constellation runnability
Barrier.
Claims (5)
1. a kind of constellation navigation method suitable for self-organizing constellation, which comprises the steps of:
A, the constellation period of self-organizing constellation is calculated according to the running track of each satellite；
B, single star navigation is carried out to every satellite；
C, according to every satellite and its with visible star apart from it is nearest at the time of the entire constellation period node division and mark
Each node is arranged each satellite according to the number of the visible star of satellite, is communicated between first order star using the visible least satellite of star number mesh
Satellite, the satellite minimum telecommunication satellite visible frequencies between upper level star according to preferential selection is as telecommunication satellite between next stage star
Principle be that the moment is communicated between communications satellite and star between every satellite and its visible satellite choose star, wherein
The Dynamic Programming Idea of operational research is used to lead between communications satellite and star between every satellite and its visible satellite selection star
The moment is interrogated, specifically: telecommunication satellite is between choosing stars at different levels since first order satellite to construct communication loop between star, every level-one star
Between between communications satellite and upper level star communications satellite the communication moment between current level star between communications satellite and upper level star lead to
Interrogate satellite for the first time apart from it is nearest at the time of, when communications satellite repeats or has multiple stars between communications satellite and higher level's star between junior's star
Between communication loop when, choose the satellite time low with telecommunication satellite visible frequencies between upper level star as communicating between next stage star and defend
Star；
D, in satellite transit, communications satellite transmits Cross-Link measurement information and single star navigation between communicating moment Shi Yuqi star between star
Information；
E, all Cross-Link measurement information and single star navigation information of the entire constellation of fusion treatment.
2. a kind of constellation navigation method suitable for self-organizing constellation according to claim 1, which is characterized in that step A institute
The constellation period that self-organizing constellation is calculated according to the running track of each satellite is stated, method particularly includes: observation satellite running track,
Satellite with identical or very much like running track is divided into one group and each satellite in every group of satellite is marked,
Using the least common multiple of each group period of satellite as the constellation period of self-organizing constellation.
3. a kind of constellation navigation method suitable for self-organizing constellation according to claim 1 or claim 2, which is characterized in that step B
Single star navigation is carried out to every satellite using the magnetic navigation method based on magnetometer, filtering mode passes through adaptive spreading kalman
Filtering algorithm realization, real-time estimation variance are as follows:Wherein, k indicates measurement moment, k
Pass through sliding data window length W measurement, dkIt is k moment filter actual observed value and the observation that the k-1 moment predicts the k moment
The difference of value, i=k-W+1, diThe difference for the observation that be i moment filter actual observed value and i-1 moment predict the i moment,Estimate variance when respectively sliding data window length is k-1, k.
4. a kind of constellation navigation method suitable for self-organizing constellation according to claim 1, which is characterized in that in step D
The Cross-Link measurement information includes distance measure and clock deviation measured value.
5. a kind of constellation navigation method suitable for self-organizing constellation according to claim 1, which is characterized in that step E is adopted
All Cross-Link measurement information and single star navigation information of entire constellation are handled with adaptive extended kalman filtering algorithm fusion.
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| CN103033188A (en) * | 2012-12-24 | 2013-04-10 | 中国科学院国家授时中心 | Navigation satellite autonomous time synchronization method based on synthetic aperture observation |
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