CN1924606A - Dipper double stars system based fast method for detecting carrier status - Google Patents

Abstract

This invention discloses one method based on Big double star system rapid measurement pose, which comprises the following steps: at initial time t0, putting antenna one and two along the measurement direction needed to get the vector r(t0) length L and t0 first set load wave phase observation values; changing the original moving base line length as k1 times along base line direction to get the new vector k1r(t0) to get second set of load wave phase valuesDeltphi<1</SUP>12(t1),Deltphi<2</SUP>12(t1); getting several groups of observations to get the direction angle phi and pitching angle thetato fulfill the measurement.

Description

Method based on the quick measurement attitude of carrier of double satellite receiver system

One, technical field

The present invention relates to a kind of method of measuring attitude of carrier, relate in particular to a kind of double satellite receiver system that utilizes and carry out the method that carrier is measured.

Two, background technology

Attitude measurement under the double satellite receiver system is the important applied field of triones navigation system, is that the receiver antenna baseline vector that solves under the navigation coordinate system of carrier phase information is tried to achieve attitude via satellite, and key problem is finding the solution of integer ambiguity.Because the number of satellite of triones navigation system is few at present, the method for finding the solution integer ambiguity commonly used in the GPS navigation system such as least square search realizes having any problem under the double satellite receiver system.The method of the domestic attitude measurement of having developed and related system have adopted rotation baseline (Lu bright clear, Hu Xiaoping, Wu Meiping at present, " utilizing rotation baseline method to carry out double star slewing ", Acta Astronautica, 2004,25 (2): .158-162), the many antenna configurations (Wu Jie in parallel channel, appoint tawny daylily, the little equality of Hu, " double star is decided the Modeling Research of appearance ", " space science journal ", 1999,19 (2): 154-159) etc. method is carried out asking for of attitude of carrier.But have certain deficiency in actual applications, for example rotate base-line method and require baseline and rotating shaft direct cross, the baseline anglec of rotation needs accurately to measure; Many antenna configurations length baseline is difficult for waiting in the same way, and rapidity and accuracy that these factors are all measured attitude of carrier easily impact.Therefore need a kind of easy and simple to handle, attitude measurement Big Dipper survey accurately appearance system.

Three, summary of the invention

1, goal of the invention: the purpose of this invention is to provide a kind of method that attitude of carrier is measured of in the double satellite receiver system, carrying out quickly and accurately.

2, technical scheme: in order to reach above-mentioned goal of the invention, method of the present invention comprises the following steps:

(1) at initial time t ₀, place antenna 1 and antenna 2 along the direction that needs are measured, make the antenna base direction parallel with direction of measurement or on same direction, record baseline vector then Length L, t ₀First group of carrier phase observation data Δ  constantly ₁₂ ¹(t ₀), Δ  ₁₂ ²(t ₀) (Δ  ₁₂ ¹(t ₀), Δ  ₁₂ ²(t ₀) be respectively the single poor observed reading of carrier phase of antenna 1,2 relative i (i=1,2) number big-dipper satellites), the unit vector of antenna 1 and big-dipper satellite 1,2 direction of visual lines With

(2) at t ₁Constantly, prolonging the described base length of step (1) along former baseline direction portable antenna 2 is original k ₁Doubly, obtain new baseline vector Record in new baseline vector

Under second group of carrier phase observation data Δ  ₁₂ ¹(t ₁), Δ  ₁₂ ²(t ₁);

(3) keep base direction constant, the described base length of portable antenna 2 prolongation steps (1) is original k again ₂Doubly, obtain new baseline vector

Record at t ₂The 3rd group of carrier phase observation data Δ  constantly ₁₂ ¹(t ₂), Δ  ₁₂ ²(t ₂);

(4) prolong base length and keep base direction constant by portable antenna 2 so successively, at t _nConstantly can get n+1 group observations (n ∈ N), corresponding baseline sequence is $\stackrel{r}{r}\left(t_0\right),k_1\stackrel{r}{r}\left(t_0\right),k_2\stackrel{r}{r}\left(t_0\right)\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;k_n\stackrel{r}{r}\left(t_0\right),$ K wherein _j＞1, j=1,2, L, n; Above-mentioned measuring process is expressed as follows:

In the formula (1): λ is a carrier wavelength, ε ⁱ(t) be observation noise, the measurement mechanism connection layout as shown in Figure 1, schematic diagram is as shown in Figure 2;

(5) because antenna 1 keeps motionless, and big-dipper satellite is the relative geostationary of geostationary satellite, so the unit vector of the contained antenna 1 of (1) formula and big-dipper satellite 1,2 direction of visual lines in the step (4), has following relation:

$\left.\begin{array}{c}\stackrel{V_1}{e}\left(t_0\right)=\stackrel{V_1}{e}\left(t_1\right)=L=\stackrel{V_1}{e}\left(t_n\right)\\ \stackrel{V_2}{e}\left(t_0\right)=\stackrel{V_2}{e}\left(t_1\right)=L=\stackrel{V_2}{e}\left(t_n\right)\end{array}\right\}---\left(2\right)$

With (2) formula substitution (1) formula, and ignore and measure noise ε, can obtain n and organize initial integer ambiguity, be shown below:

From (3) formula as can be seen, the most ideally just can be in the hope of initial integer ambiguity parameter N as long as prolong a baseline ₁(t ₀), N ₂(t ₀).But the cycle slip that occurs in the prolongation process can suitably increase the prolongation number of times, obtains a plurality of candidate values.If the many groups N that is tried to achieve ₁(t ₀), N ₂(t ₀) value identical, then showing does not have cycle slip; If different, then cycle slip has taken place in proof, need remeasure repeating step (1)～(5);

(6) obtaining N ₁(t ₀), N ₂(t ₀) after, bring following formula (4) into and ignore measurement noise ε, just can be in the hope of the baseline vector initial value

ε in the formula _LIt is the base length measuring error;

(7) obtaining of attitude: the baseline vector of trying to achieve in the step (6) is generally represented with direct coordinate system, is established $\stackrel{r}{r}\left(t_0\right)={\left[\begin{array}{ccc}x& y& z\end{array}\right]}^T$ (sky, northeast coordinate system), then the position angle ψ and the pitching angle theta of baseline are respectively:

$\left.\begin{array}{c}\mathrm{\&psi;}=\arctan (x/y)\\ \mathrm{\&theta;}=\arctan (z/\sqrt{x^2+y^2})\end{array}\right\}---\left(5\right)$

It should be noted that and work as

Exist when bilingual, can draw two groups of attitude angle, how correctly to choose attitude angle and can judge,, thereby reject wrong value, obtain the correct attitude of baseline as baseline summary level etc. whether with the priori conditions of baseline.

3, beneficial effect

Method of the present invention has following advantage: (1) this method simple operation, and only need portable antenna to get final product, it is fast that attitude is asked for speed; (2) required measurement mechanism is simple, only needs basic, the most common equipment such as antenna, linear measure longimetry device, satellite carrier signal receiver and data processor, does not need special utility appliance such as rotating mechanism, and the installation of antenna does not have specific (special) requirements yet; The experiment proved that (3) this method can provide the accurate position angle and the angle of pitch.

The above beneficial effect of the invention is described as follows:

(1) measurement mechanism is simple, does not have special accuracy requirement:

As shown in Figure 2, suppose α ⁱBe baseline and unit vector The angle of (i=1,2), base line extension precision are σ _L, the carrier phase measurement precision is σ _ψ, the base line extension multiple is k _m, can get σ by deriving by formula (3), (4) _L, σ _ψ, k _mBetween restriction relation:

${\mathrm{\&sigma;}}_L<\frac{\mathrm{\&lambda;}(k_m-1){\mathrm{\&sigma;}}_{\mathrm{\&psi;}}}{\cos {\mathrm{\&alpha;}}^i}---\left(6\right)$

As seen from the above equation at carrier phase measurement precision (σ _ψ) and baseline vector direction (α ⁱ) determine under the situation k _mBig more, desired base line extension precision is low more.

Suppose α ¹=45 °, if the carrier phase precision got for 1%, 2%, 3% week respectively, base line extension multiple under the different carrier phase accuracy that can draw and base line extension accuracy relation curve, as shown in Figure 3.As can be seen from Figure 3, the base line extension multiple gets 4, is respectively 1%, 2% in the carrier phase precision, and 3% o'clock, the corresponding base line extension precision that requires only was better than 0.005m, 0.01m, and 0.015m can successfully determine initial integer ambiguity, thereby solves attitude angle.Consider that from the engineering practical standpoint base line extension precision such for 5 millimeters (0.005m) is easy to realize.Explanation prolongation base-line method is not high to the accuracy requirement of base line extension thus, is easy to realize.

(2) base line extension method single-point orientation accuracy

Suppose Big Dipper receiver location for (50m), base length is 1.5m at the beginning for 118.8139 ° of E, 32.0405 ° of N, and the base line extension multiple gets 4, carries out following two kinds of directed emulation testings:

(a) the fixed base elevation angle is 10 °, and the rotation baseline rotates 1 ° at every turn, records the position angle and the angle of pitch precision (1 σ) that record after each rotation, and the precision change curve as shown in Figure 4;

(b) the constant bearing angle is 70 °, in [90 °, 90 °] interval variation, tries to achieve the attitude accuracy (1 σ) under each angle of pitch by the angle of pitch, and the precision change curve as shown in Figure 5.

For the ease of expression, the y axle of Fig. 4, Fig. 5 has all adopted logarithmic coordinate.As can be seen from Figure 4, attitude accuracy is along with azimuthal variation forms cyclical variation, when the baseline deviation North and South direction in ± 50 °, the position angle and the angle of pitch can be realized 0.01 ° precision.

As can be seen from Figure 5, under the fixation case of position angle, attitude accuracy also can be along with the angle of pitch changes and different, and the angle of pitch is big more, and attitude accuracy is high more.Explanation thus when baseline slewing, also can further improve orientation accuracy as increasing the angle of pitch.

(3) base line extension method zone orientation accuracy:

What more than provide only is the attitude accuracy that obtains at the somewhere single-point, for the general adaptability that prolongs base-line method is described, east longitude is 70 °～145 ° between the service area of big-dipper satellite, 5 °～55 ° such one of north latitude covers two kinds of emulation doing in the national scope in (2), statistics is at the maximin of each position azimuthal and angle of pitch precision (1 σ), thereby obtains prolonging attitude measurement accuracy under the base-line method with the distribution situation of change in location.

The situation of change of the angular accuracy of simulating scheme (a) and (b) correspondence.Respectively as Fig. 6, shown in Figure 7, among the figure in the three dimensional space coordinate up and down the space between two curved surfaces be exactly the variation range of angle-measurement accuracy.

Fig. 6 (a) shows, have under the fixed angle of altitude situation at baseline and to prolong basal orientation, region-wide scope interior orientation angular accuracy is greatly between 0.001 °～1 °, it can also be seen that from Fig. 6 (a) error variance maximal value curved surface is tilted by north orientation south, illustrates that the orientation accuracy of low latitudes can also be higher in addition.The precision situation of the angle of pitch is identical with the position angle under the fixed angle of altitude that Fig. 6 (b) shows.

Fig. 7 (a) and (b) show that under the baseline fix fixation case, by adjusting the angle of pitch, position angle and angle of pitch accuracy rating are all between 0.001 °～0.1 °; And precision is evenly distributed in gamut substantially, the situation that does not have appearance to change with longitude and latitude.

Above-mentioned the analysis showed that prolongs the base-line method measurement position angle and the angle of pitch and is not subjected to the restriction of region, all can use in the big-dipper satellite service range.It is to be noted in addition, above conclusion is is 1.5m in base length, prolong multiple is to obtain under 4 the condition, further l-G simulation test shows, under the situation of base length or the increase of prolongation multiple, the attitude accuracy that above emulation obtains can also further improve, and can satisfy more high-precision demand.

Four, description of drawings

The device synoptic diagram of Fig. 1 this method;

Fig. 2 asks for single poor integer ambiguity synoptic diagram for prolonging baseline;

Fig. 3 is base line extension multiple and base line extension accuracy relation curve;

Fig. 4 is for prolonging the attitude accuracy curve under the directed different orientations of base-line method single-point;

Fig. 5 is for prolonging the attitude accuracy curve under the directed different angles of pitch of base-line method single-point;

Fig. 6 (a) is the measurement of azimuth precision interval graph under the fixation case of the region-wide interior elevation angle;

Fig. 6 (b) is the angle of pitch measuring accuracy interval graph under the fixation case of the region-wide interior elevation angle;

Fig. 7 (a) is the measurement of azimuth precision interval graph under the fixation case of angle, region-wide interior orientation;

Fig. 7 (b) is the angle of pitch measuring accuracy interval graph under the fixation case of angle, region-wide interior orientation.

Five, embodiment

Embodiment 1: as shown in Figure 1 and Figure 2, the method based on the quick measurement attitude of carrier of double satellite receiver system of present embodiment comprises the following steps:

(1) at initial time t ₀, place antenna 1 and antenna 2 along the direction that needs are measured, make the antenna base direction parallel with direction of measurement or on same direction, record baseline vector then Length L=4m, t ₀First group of carrier phase observation data Δ  constantly ₁₂ ¹(t ₀), Δ  ₁₂ ²(t ₀) (Δ  ₁₂ ¹(t ₀), Δ  ₁₂ ²(t ₀) be respectively the single poor observed reading of carrier phase of antenna 1,2 relative i (i=1,2) number satellites), the unit vector of antenna 1 and big-dipper satellite 1,2 direction of visual lines

(2) at t ₁Constantly, prolonging the described base length of step (1) along former baseline direction portable antenna 2 is original k ₁=1.5 times, obtain new baseline vector Record in new baseline vector

Under second group of carrier phase observation data Δ  ₁₂ ¹(t ₁), Δ  ₁₂ ²(t ₁);

(3) keep base direction constant, the described base length of portable antenna 2 prolongation steps (1) is original k again ₂=2 times, obtain new baseline vector

Record at t ₂The 3rd group of carrier phase observation data Δ  constantly ₁₂ ¹(t ₂), Δ  ₁₂ ²(t ₂);

(4) like this at t ₂Constantly can get the 2+1 group observations, corresponding baseline sequence is $\stackrel{r}{r}\left(t_0\right),k_1\stackrel{r}{r}\left(t_0\right),k_2\stackrel{r}{r}\left(t_0\right),$ Above-mentioned measuring process is expressed as follows:

In the formula (1): λ is a carrier wavelength, ε ⁱ(t) be observation noise, the measurement mechanism connection layout as shown in Figure 1, schematic diagram is as shown in Figure 2;

(5) because antenna 1 keeps motionless, and big-dipper satellite is the relative geostationary of geostationary satellite, so the unit vector of the contained antenna 1 of (1) formula and big-dipper satellite 1,2 direction of visual lines in the step (4), has following relation:

$\left.\begin{array}{c}\stackrel{V_1}{e}\left(t_0\right)=\stackrel{V_1}{e}\left(t_1\right)=\stackrel{V_1}{e}\left(t_2\right)\\ \stackrel{V_2}{e}\left(t_0\right)=\stackrel{V_2}{e}\left(t_1\right)=\stackrel{V_2}{e}\left(t_2\right)\end{array}\right\}---\left(2\right)$

With (2) formula substitution (1) formula, and ignore and measure noise ε, can obtain 2 groups of initial integer ambiguities, be shown below:

If two groups of N that tried to achieve ₁(t ₀), N ₂(t ₀) value identical, showing does not have cycle slip; If different, then cycle slip has taken place in proof, need remeasure repeating step (1)～(5).

(6) obtaining N ₁(t ₀), N ₂(t ₀) after, bring following formula (4) into and ignore measurement noise ε, just can be in the hope of the baseline vector initial value

ε in the formula _LIt is the base length measuring error;

(7) obtaining of attitude: the baseline vector of trying to achieve is generally represented with direct coordinate system, is established $\stackrel{r}{r}\left(t_0\right)={\left[\begin{array}{ccc}x& y& z\end{array}\right]}^T$ (sky, northeast coordinate system), then the position angle ψ and the pitching angle theta of baseline are respectively:

$\left.\begin{array}{c}\mathrm{\&psi;}=\arctan (x/y)\\ \mathrm{\&theta;}=\arctan (z/\sqrt{x^2+y^2})\end{array}\right\}---\left(5\right)$

It should be noted that and work as Exist when bilingual, can obtain two groups of attitude angle, how correctly to choose attitude angle and can judge with the priori conditions of baseline.As baseline summary level etc. whether, thereby pick out wrong value, obtain the correct attitude of baseline.

In the present embodiment, prolonged baseline twice, the number of times that can also determine to prolong baseline according to the requirement of actual measurement precision can record attitude of carrier as 3 times, 4 inferior equally by above-mentioned step.

Claims (1)

1, a kind of method of the quick measurement attitude of carrier based on the double satellite receiver system is characterized in that this method comprises the following steps:

(1) at initial time t ₀, place antenna (1) and antenna (2) along the direction that needs are measured, make the antenna base direction parallel with direction of measurement or on same direction, record baseline vector then

Length L, t ₀First group of carrier phase observation data Δ  constantly ₁₂ ¹(t ₀), Δ  ₁₂ ²(t ₀), Δ  ₁₂ ¹(t ₀), Δ  ₁₂ ²(t ₀) be respectively antenna (1), antenna (2) with respect to the single poor observed reading of the carrier phase of i (i=1,2) number satellite, and the unit vector of antenna (1) and big-dipper satellite (1,2) direction of visual lines

(2) at t ₁Constantly, prolonging the described base length of step (1) along former baseline direction portable antenna 2 is original k ₁Doubly, obtain new baseline vector

Record in new baseline vector

Under second group of carrier phase observation data Δ  ₁₂ ¹(t ₁), Δ  ₁₂ ²(t ₁);

(3) keep base direction constant, the described base length of portable antenna 2 prolongation steps (1) is original k again ₂Doubly, obtain new baseline vector

Record at t ₂The 3rd group of carrier phase observation data Δ  constantly ₁₂ ¹(t ₂), Δ  ₁₂ ²(t ₂);

(4) prolong base length and keep base direction constant by portable antenna 2 so successively, at t _nConstantly can get n+1 group observations (n ∈ N), corresponding baseline sequence is

K wherein _j＞1, j=1,2, L, n; Above-mentioned measuring process is expressed as follows:

λ is a carrier wavelength in the formula (1), ε ⁱ(t) be observation noise;

The contained antenna (1) of formula (1) closes with the unit vector of big-dipper satellite (1,2) direction of visual lines and is:

$\left.\begin{array}{c}\stackrel{V_1}{e}\left(t_0\right)=\stackrel{V_1}{e}\left(t_1\right)=L=\stackrel{V_1}{e}\left(t_n\right)\\ \stackrel{V_2}{e}\left(t_0\right)=\stackrel{V_2}{e}\left(t_1\right)=L=\stackrel{V_2}{e}\left(t_n\right)\end{array}\right\}---\left(2\right)$

With (2) formula substitution (1) formula, and ignore and measure noise ε, can obtain n and organize initial integer ambiguity, be shown below:

(6) obtaining N ₁(t ₀), N ₂(t ₀) after, bring following formula (4) into and ignore measurement noise ε, just can be in the hope of the baseline vector initial value

ε in the formula _LIt is the base length measuring error;

(7) obtaining of attitude: the baseline vector of trying to achieve is represented with direct coordinate system, is established $\stackrel{r}{r}\left(t_0\right)={\left[\begin{array}{ccc}x& y& z\end{array}\right]}^T$ (sky, northeast coordinate system), then the position angle ψ and the pitching angle theta of baseline are respectively:

$\left.\begin{array}{c}\mathrm{\&psi;}=\arctan (x/y)\\ \mathrm{\&theta;}=\arctan (z/\sqrt{x^2+y^2})\end{array}\right\}---\left(5\right)$

So far finished the measurement of attitude of carrier.

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