CN102650694B - Medium-long baseline ambiguity resolution method based on BeiDou four-frequency signal - Google Patents

Abstract

The invention discloses a medium-long baseline ambiguity resolution method based on a BeiDou four-frequency signal. The method comprises the following steps of: S1, working out two wide-lane ambiguities by utilizing a four-frequency combination pseudorange and a four-frequency combination carrier; S2, working out the pseudorange of a deionized layer and the delay of a double-difference ionized layer with a frequency point B1 by utilizing the double-difference observed quantities and the corresponding ambiguities of two wide-lane carrier phases; S3, working out two ambiguities related to a fourth frequency according to the pseudorange of the deionized layer and the delay of the double-difference ionized layer with the frequency point B1; and S4, working out the independent ambiguity of a BeiDou four-frequency carrier according to the four ambiguities worked out in the S1-S3. According to the medium-long baseline ambiguity resolution method based on the BeiDou four-frequency signal, under the condition of a medium-long baseline, the independent ambiguity of the four-frequency carrier is rapidly and reliably resolved by adopting the four-frequency combination pseudorange and the four-frequency combination carrier. Compared with a three-frequency method, the ambiguity resolution time is greatly shortened and the ambiguity fixed success rate is effectively increased by the medium-long baseline ambiguity resolution method based on the BeiDou four-frequency signal.

Description

Middle long baseline Ambiguity Solution Methods based on the Big Dipper four frequency signals

Technical field

The present invention relates to GLONASS (Global Navigation Satellite System) (Global Navigation SatelliteSystem, GNSS) Technology Precision field, particularly a kind of middle long baseline Ambiguity Solution Methods based on the Big Dipper four frequency signals.

Background technology

GNSS multifrequency solution of fuzzy degree is the important step of GNSS high-acruracy survey.Ambiguity resolution mainly contains two kinds of patterns: geometric mode and without geometric mode.

LAMBDA method (Least-squares AMBiguity DecorrelationAdjustment) belongs to geometric mode, first determine the search volume of containing alternative blur level combination, secondly Ambiguity Search Space is carried out to integer transform and sequential conditional search, finally the blur level optimum solution after integer conversion is carried out to inverse transformation, thereby obtain best blur level.LAMBDA method blur level search speed is very fast, and reliability is higher, but is only applicable to short base measurement.

Under middle long base line condition, due to the ambiguity resolution based on geometric mode, affected by satellite orbit, tropospheric delay, ionosphere delay equal error larger, and the success ratio of its ambiguity resolution is lower.Therefore in recent years, three frequency carrier waves mainly concentrated on without geometric mode in the applied research aspect middle long baseline.Three early stage frequency ambiguity resolution (Three Carrier AmbiguityResolution, TCAR) method and Ambiguity Solution Methods (the Cascading IntegerResolution that goes forward one by one, CIR) be all based on without geometric mode, adopt recurrence method, progressively calculate combinational fuzzy degree ，Ji Chaokuan Xiang,Kuan lane, the narrow lane ambiguity that wavelength successively decreases.Because CIR method adopts, round method directly fixedly Chao Kuan Xiang,Kuan lane, narrow lane ambiguity nearby, affected by two poor Ionosphere Residual Error, two poor observation noise larger, therefore, CIR method is only applicable to very-short-reach ambiguity resolution.Adopt TCAR method recursion to calculate Chao Kuan Xiang,Kuan lane, narrow lane ambiguity, be only subject to multiple measurement noise effect, can be used for middle long baseline ambiguity resolution, but the blur level set time is longer.

Visible said method has certain limitation during long baseline high-acruracy survey in being applied to GNSS.

Summary of the invention

(1) technical matters that will solve

The technical problem to be solved in the present invention is: under middle long base line condition, how to utilize the Big Dipper four frequency signals to resolve carrier phase ambiguity, to shorten solution of fuzzy degree evaluation time, effectively improve blur level and be fixed into power.

(2) technical scheme

For solving the problems of the technologies described above, the invention provides a kind of middle long baseline Ambiguity Solution Methods based on the Big Dipper four frequency signals, comprise the following steps:

S1: utilize four frequency combined pseudoranges and four frequency combined carriers to calculate two wide lane ambiguities;

S2: utilize double difference and the corresponding blur level of Liang Gekuan lane carrier phase, calculate the two poor ionosphere delay of deion layer pseudorange and B1 frequency;

S3: the two poor ionosphere delay according to deion layer pseudorange and B1 frequency, calculates two blur leveles with the 4th frequency dependence;

S4: four blur leveles that calculate according to S1～S3 are calculated the Big Dipper four independent blur level of carrier wave frequently.

Wherein, described step S1 specifically comprises:

S1.1: construct four frequency combined pseudoranges and four combined carriers frequently;

The observation equation of Big Dipper pseudorange, carrier phase is respectively:

$P_i=\mathrm{\ρ}(t_s,t_r)+C({\mathrm{dt}}_r-{\mathrm{dt}}_s)+d_{\mathrm{orb}}+d_{\mathrm{trop}}+\frac{K}{f_i^2}+M_{\mathrm{Pi}}+{\mathrm{\ϵ}}_{\mathrm{Pi}}---\left(1\right)$

In formula, subscript i represents carrier wave B _iwith S relevant parameter, i=1,2,3; P _ifor carrier wave B _iwith the corresponding pseudo range observed quantity of S, unit is rice; Φ _i,

be respectively carrier wave B _ibe respectively rice, week with the phase observations Liang， unit of S; λ _ifor carrier wave B _iwith the wavelength of S, unit is rice; N _ifor carrier wave B _iwith the integer ambiguity of S, unit is week; Dt _s, dt _rbe respectively satellite clock correction, receiver clock correction, unit is second; C is the light velocity, and unit is meter per second;

for carrier wave B _iwith the corresponding ionosphere delay of S, unit is rice; f _ifor carrier wave B _iwith the frequency of S, unit is hertz; d _tropfor tropospheric retardation, unit is rice; M _pi, M _{Φ i}be respectively B _iwith the multipath effect of pseudorange, carrier phase on S frequency, unit is rice; ε _pi, ε _{Φ i}be respectively the observation noise of pseudorange, carrier phase, unit is rice; ρ be satellite to the geometric distance of receiver antenna, unit be rice;

Yi Zhouwei unit, the general type of four frequency combined carriers is:

Yi meter Wei unit, the general type of four frequency combined carriers is:

${\mathrm{\Φ}}_{i,j,k,m}=\frac{i\·f_1\·{\mathrm{\Φ}}_1+j\·f_2\·{\mathrm{\Φ}}_2+k\·f_3\·{\mathrm{\Φ}}_3+m\·f_4\·{\mathrm{\Φ}}_4}{i\·f_1+j\·f_2+k\·f_3+m\·f_4}---\left(4\right)$

The blur level of combined carriers, frequency and wavelength are respectively:

N _{i，j，k，m}＝iN ₁+jN ₂+kN ₃+mN ₄ (5)

f _{i，j，k，m}＝if ₁+jf ₂+kf ₃+mf ₄ (6)

${\mathrm{\λ}}_{i,j,k,m}=\frac{C}{f_{i,j,k}}=\frac{{\mathrm{\λ}}_1{\mathrm{\λ}}_2{\mathrm{\λ}}_3{\mathrm{\λ}}_4}{i\·{\mathrm{\λ}}_2{\mathrm{\λ}}_3{\mathrm{\λ}}_4+j\·{\mathrm{\λ}}_1{\mathrm{\λ}}_3{\mathrm{\λ}}_4+k{\mathrm{\λ}}_1{\mathrm{\λ}}_2{\mathrm{\λ}}_4+m{\mathrm{\λ}}_1{\mathrm{\λ}}_2{\mathrm{\λ}}_3}---\left(7\right)$

The general type of four frequency combined pseudoranges is:

$P_{a,b,c,d}=\frac{a\·f_1\·P_1+b\·f_2\·P_2+c\·f_3\·P_3+d\·f_4\·P_4}{a\·f_1+b\·f_2+c\·f_3+d\·f_4}$

Four frequency combined pseudoranges and the four frequently observation equation of combined carriers are expressed as:

$P_{a,b,c,d}=\mathrm{\ρ}+C({\mathrm{dt}}_r-{\mathrm{dt}}_s)+d_{\mathrm{orb}}+d_{\mathrm{trop}}+{\mathrm{\β}}_{a,b,c,d}\·\frac{K}{f_1^2}+{\mathrm{\ϵ}}_{P_{a,b,c,d}}---\left(9\right)$

In formula,

for B1 frequency ionosphere delay, β _{a, b, c, d}and β _{i, j, k, m}be respectively the ionosphere coefficient of combined pseudorange, combined carriers:

${\mathrm{\β}}_{a,b,c,d}=(\frac{a}{f_1}+\frac{b}{f_2}+\frac{c}{f_3}+\frac{d}{f_4})\·\frac{f_1^2}{f_{a,b,c,d}}---\left(11\right)$

${\mathrm{\β}}_{i,j,k,m}=(\frac{i}{f_1}+\frac{j}{f_2}+\frac{k}{f_3}+\frac{m}{f_4})\·\frac{f_1^2}{f_{i,j,k,m}}---\left(12\right)$

with

be respectively the observation noise of combined pseudorange, combined carriers;

According to pseudorange combination coefficient (a, b, c, d) and carrier combination coefficient (i, j, k, m), calculate four frequency combined pseudoranges and four combined carriers frequently;

S1.2: the double difference of tectonic association pseudorange and combined carriers, equation is as follows:

$\▿\mathrm{\Δ}{P}_{a,b,c,d}=\▿\mathrm{\Δ\ρ}(t_s,t_r)+\▿\mathrm{\Δ}{d}_{\mathrm{orb}}+\▿\mathrm{\Δ}{d}_{\mathrm{trop}}+{\mathrm{\β}}_{a,b,c,d}\·\frac{\▿\mathrm{\ΔK}}{f_1^2}+\▿\mathrm{\Δ}{M}_P+\▿\mathrm{\Δ}{\mathrm{\ϵ}}_{P_{a,b,c,d}}---\left(13\right)$

S1.3: utilize the double difference of combined pseudorange and combined carriers to calculate wide lane ambiguity, computing formula is:

$\▿\mathrm{\Δ}{N}_{i,j,k,m}=\mathrm{int}[\frac{{\▿\mathrm{\Δ\Φ}}_{i,j,k,m}-{\▿\mathrm{\ΔP}}_{a,b,c,d}}{{\mathrm{\λ}}_{i,j,k,m}}+\frac{{\mathrm{\β}}_{i,j,k,m}+{\mathrm{\β}}_{a,b,c,d}}{{\mathrm{\λ}}_{i,j,k,m}}\·\frac{\▿\mathrm{\ΔK}}{f_1^2}-\frac{{\▿\mathrm{\Δ\ϵ}}_{{\mathrm{\Φ}}_{i,j,k,m}-{\▿\mathrm{\Δ\ϵ}}_{P_{a,b,c,d}}}}{{\mathrm{\λ}}_{i,j,k,m}}]---\left(15\right)$

In formula,

represent two poor operators, int[] represent to round up.

Wherein, in step S1, adopt combined pseudorange

and combined carriers

calculate wide lane ambiguity

adopt combined pseudorange

and combined carriers

calculate wide lane ambiguity

Wherein, in described step S2, calculate the formula of two poor ionosphere delays of deion layer pseudorange and B1 frequency as follows:

$\▿\mathrm{\Δ\ρ}=\frac{f_2}{f_2-f_3}({\▿\mathrm{\Δ\Φ}}_{i1,j1,k1,m1}-{\▿\mathrm{\ΔN}}_{i1,j1,k1,m1}\·{\mathrm{\λ}}_{i1,j1,k1,m1})---\left(16\right)$

$-\frac{f_3}{f_2-f_3}({\▿\mathrm{\Δ\Φ}}_{i2,j2,k2,m2}-{\▿\mathrm{\ΔN}}_{i2,j2,k2,m2}\·{\mathrm{\λ}}_{i2,j2,k2,m2})$

$\frac{\▿\mathrm{\ΔK}}{f_1^2}=\frac{f_2{f}_3}{f_1(f_2-f_3)}[({\▿\mathrm{\Δ\Φ}}_{i1,j1,k1,m1}-{\▿\mathrm{\ΔN}}_{i1,j1,k1,m1}\·{\mathrm{\λ}}_{i1,j1,k1,m1})---\left(17\right)$

$-({\▿\mathrm{\Δ\Φ}}_{i2,j2,k2,m2}-{\▿\mathrm{\ΔN}}_{i2,j2,k2,m2}\·{\mathrm{\λ}}_{i2,j2,k2,m2})]$

In formula,

represent deion layer pseudorange,

the two poor ionosphere delay that represents B1 frequency, (i1, j1, k1, m1) and (i2, j2, k2, m2) is carrier combination coefficient.

Wherein, described step S3 specifically comprises:

S3.1: the combined carriers double difference of calculating and the 4th frequency dependence, equation is:

${\▿\mathrm{\Δ\Φ}}_{i,j,k,m}=\▿\mathrm{\Δ\ρ}-{\mathrm{\β}}_{i,j,k,m}\·\frac{\▿\mathrm{\ΔK}}{f_1^2}+{\▿\mathrm{\ΔN}}_{i,j,k,m}{\mathrm{\λ}}_{i,j,k,m}+{\▿\mathrm{\Δ\ϵ}}_{{\mathrm{\Φ}}_{i,j,k,m}}---\left(18\right)$

In formula, (i, j, k, m) is integer, and m ≠ 0;

S3.2: calculate the blur level with the 4th frequency dependence:

By deion layer pseudorange two poor ionosphere delay with B1 frequency

substitution formula (18), obtains blur level

${\▿\mathrm{\ΔN}}_{i,j,k,m}=\mathrm{int}[\frac{{\▿\mathrm{\Δ\Φ}}_{i,j,k,m}-\▿\mathrm{\Δ\ρ}}{{\mathrm{\λ}}_{i,j,k,m}}+\frac{{\mathrm{\β}}_{i,j,k,m}}{{\mathrm{\λ}}_{i,j,k,m}}\·\frac{\▿\mathrm{\ΔK}}{f_1^2}+{\mathrm{\ϵ}}_{{\▿\mathrm{\ΔN}}_{i,j,k,m}}]---\left(19\right)$

In formula, for blur level random noise;

S3.3: smoothing processing, by blur level

carry out the smoothing processing of 2～3 minutes, can obtain reliably

Wherein, in step S3, select carrier combination coefficient (0,0 ,-1,1) and (1,0 ,-6,6), calculate the blur level with the 4th frequency dependence

Wherein, the mode of the independent blur level of the described step S4 calculating Big Dipper four frequency carrier waves is:

Utilize four blur leveles that calculated

with

according to formula (20)～(23), calculate respectively the independent blur level of B1, B2, B3, each carrier wave of S

with

$\▿\mathrm{\Δ}{N}_1=6{\▿\mathrm{\ΔN}}_{\mathrm{0,0},-\mathrm{1,1}}-{\▿\mathrm{\ΔN}}_{-\mathrm{1,0},-\mathrm{6,6}}---\left(20\right)$

${\▿\mathrm{\ΔN}}_2={\▿\mathrm{\ΔN}}_1-{\▿\mathrm{\ΔN}}_{1,-\mathrm{1,0,0}}---\left(21\right)$

${\▿\mathrm{\ΔN}}_3={\▿\mathrm{\ΔN}}_1-{\▿\mathrm{\ΔN}}_{\mathrm{1,0},-\mathrm{1,0}}---\left(22\right)$

${\▿\mathrm{\ΔN}}_4=7\▿\mathrm{\Δ}{N}_{\mathrm{0,0},-\mathrm{1,1}}-({\▿\mathrm{\ΔN}}_{-\mathrm{1,0},-\mathrm{6,6}}+{\▿\mathrm{\ΔN}}_{\mathrm{1,0},-\mathrm{1,0}}).---\left(23\right)$

(3) beneficial effect

The present invention is under middle long base line condition, adopt four frequency combined pseudoranges and four combined carriers frequently, quickly and reliably calculated the independent blur level of four frequency carrier waves, with respect to three frequency methods, the method has shortened solution of fuzzy degree evaluation time greatly, has effectively improved blur level and has been fixed into power.

Accompanying drawing explanation

Fig. 1 is a kind of middle long baseline Ambiguity Solution Methods process flow diagram based on the Big Dipper four frequency signals of the embodiment of the present invention;

Fig. 2 is the particular flow sheet of step S101 in Fig. 1;

Fig. 3 is the particular flow sheet of step S103 in Fig. 1.

Embodiment

Below in conjunction with drawings and Examples, the specific embodiment of the present invention is described in further detail.Following examples are used for illustrating the present invention, but are not used for limiting the scope of the invention.

As shown in Figure 1, the middle long baseline Ambiguity Solution Methods based on the Big Dipper four frequency signals of the present invention comprises:

Step S101, utilizes four frequency combined pseudoranges and four frequency combined carriers to calculate two wide lane ambiguities.As shown in Figure 2, detailed process is as follows:

1, construct four frequency combined pseudoranges and four combined carriers frequently.

The observation equation of Big Dipper pseudorange, carrier phase is respectively:

$P_i=\mathrm{\ρ}(t_s,t_r)+C({\mathrm{dt}}_r-{\mathrm{dt}}_s)+d_{\mathrm{orb}}+d_{\mathrm{trop}}+\frac{K}{f_i^2}+M_{\mathrm{Pi}}+{\mathrm{\ϵ}}_{\mathrm{Pi}}---\left(1\right)$

In formula, subscript i represents carrier wave B _iwith S relevant parameter, i=1,2,3; P _ifor carrier wave B _iwith the corresponding pseudo range observed quantity of S, unit is rice; Φ _i,

be respectively carrier wave B _ibe respectively rice, week with the phase observations Liang， unit of S; λ _ifor carrier wave B _iwith the wavelength of S, unit is rice; N _ifor carrier wave B _iwith the integer ambiguity of S, unit is week; Dt _s, dt _rbe respectively satellite clock correction, receiver clock correction, unit is second; C is the light velocity, and unit is meter per second;

for carrier wave B _iwith the corresponding ionosphere delay of S, unit is rice; f _ifor carrier wave B _iwith the frequency of S, unit is hertz; d _tropfor tropospheric retardation, unit is rice; M _pi, M _{Φ i}be respectively B _iwith the multipath effect of pseudorange, carrier phase on S frequency, unit is rice; ε _pi, ε _{Φ i}be respectively the observation noise of pseudorange, carrier phase, unit is rice; ρ be satellite to the geometric distance of receiver antenna, unit be rice.

Yi Zhouwei unit, the general type of four frequency combined carriers is:

Yi meter Wei unit, the general type of four frequency combined carriers is:

${\mathrm{\Φ}}_{i,j,k,m}=\frac{i\·f_1\·{\mathrm{\Φ}}_1+j\·f_2\·{\mathrm{\Φ}}_2+k\·f_3\·{\mathrm{\Φ}}_3+m\·f_4\·{\mathrm{\Φ}}_4}{i\·f_1+j\·f_2+k\·f_3+m\·f_4}---\left(4\right)$

The blur level of combined carriers, frequency and wavelength are respectively:

N _{i，j，k，m}＝iN ₁+jN ₂+kN ₃+mN ₄ (5)

f _{i，j，k，m}＝if ₁+jf ₂+kf ₃+mf ₄ (6)

${\mathrm{\λ}}_{i,j,k,m}=\frac{C}{f_{i,j,k}}=\frac{{\mathrm{\λ}}_1{\mathrm{\λ}}_2{\mathrm{\λ}}_3{\mathrm{\λ}}_4}{i\·{\mathrm{\λ}}_2{\mathrm{\λ}}_3{\mathrm{\λ}}_4+j\·{\mathrm{\λ}}_1{\mathrm{\λ}}_3{\mathrm{\λ}}_4+k{\mathrm{\λ}}_1{\mathrm{\λ}}_2{\mathrm{\λ}}_4+m{\mathrm{\λ}}_1{\mathrm{\λ}}_2{\mathrm{\λ}}_3}---\left(7\right)$

The general type of four frequency combined pseudoranges is:

$P_{a,b,c,d}=\frac{a\·f_1\·P_1+b\·f_2\·P_2+c\·f_3\·P_3+d\·f_4\·P_4}{a\·f_1+b\·f_2+c\·f_3+d\·f_4}---\left(8\right)$

Four frequency combined pseudoranges and the four frequently observation equation of combined carriers are expressed as:

$P_{a,b,c,d}=\mathrm{\ρ}+C({\mathrm{dt}}_r-{\mathrm{dt}}_s)+d_{\mathrm{orb}}+d_{\mathrm{trop}}+{\mathrm{\β}}_{a,b,c,d}\·\frac{K}{f_1^2}+{\mathrm{\ϵ}}_{P_{a,b,c,d}}---\left(9\right)$

In formula,

for B1 frequency ionosphere delay, β _{a, b, c, d}and β _{i, j, k, m}be respectively the ionosphere coefficient of combined pseudorange, combined carriers:

${\mathrm{\β}}_{a,b,c,d}=(\frac{a}{f_1}+\frac{b}{f_2}+\frac{c}{f_3}+\frac{d}{f_4})\·\frac{f_1^2}{f_{a,b,c,d}}---\left(11\right)$

${\mathrm{\β}}_{i,j,k,m}=(\frac{i}{f_1}+\frac{j}{f_2}+\frac{k}{f_3}+\frac{m}{f_4})\·\frac{f_1^2}{f_{i,j,k,m}}---\left(12\right)$

with

be respectively the observation noise of combined pseudorange, combined carriers;

According to pseudorange combination coefficient (a, b, c, d) and carrier combination coefficient (i, j, k, m), calculate four frequency combined pseudoranges and four combined carriers frequently.

2, the double difference of tectonic association pseudorange and combined carriers, equation is as follows:

$\▿\mathrm{\Δ}{P}_{a,b,c,d}=\▿\mathrm{\Δ\ρ}(t_s,t_r)+\▿\mathrm{\Δ}{d}_{\mathrm{orb}}+\▿\mathrm{\Δ}{d}_{\mathrm{trop}}+{\mathrm{\β}}_{a,b,c,d}\·\frac{\▿\mathrm{\ΔK}}{f_1^2}+\▿\mathrm{\Δ}{M}_P+\▿\mathrm{\Δ}{\mathrm{\ϵ}}_{P_{a,b,c,d}}---\left(13\right)$

3, utilize combined pseudorange and combined carriers to calculate wide lane ambiguity, computing formula is:

$\▿\mathrm{\Δ}{N}_{i,j,k,m}=\mathrm{int}[\frac{{\▿\mathrm{\Δ\Φ}}_{i,j,k,m}-{\▿\mathrm{\ΔP}}_{a,b,c,d}}{{\mathrm{\λ}}_{i,j,k,m}}+\frac{{\mathrm{\β}}_{i,j,k,m}+{\mathrm{\β}}_{a,b,c,d}}{{\mathrm{\λ}}_{i,j,k,m}}\·\frac{\▿\mathrm{\ΔK}}{f_1^2}-\frac{{\▿\mathrm{\Δ\ϵ}}_{{\mathrm{\Φ}}_{i,j,k,m}-{\▿\mathrm{\Δ\ϵ}}_{P_{a,b,c,d}}}}{{\mathrm{\λ}}_{i,j,k,m}}]---\left(15\right)$

In formula,

represent two poor operators, int[] represent to round up.

For the reliable blur level of calculating, require in above formula the impact in ionosphere and noise as far as possible little.The success ratio that blur level rounds nearby depends primarily on carrier noise, pseudorange noise and three factors of carrier wavelength.

In the present embodiment, adopt combined pseudorange

and combined carriers

calculate wide lane ambiguity

adopt combined pseudorange

and combined carriers

calculate wide lane ambiguity

Step S102, utilizes double difference and the corresponding blur level of Liang Gekuan lane carrier phase, calculates the two poor ionosphere delays of deion layer pseudorange and B1 frequency.Computing formula is as follows:

$\▿\mathrm{\Δ\ρ}=\frac{f_2}{f_2-f_3}({\▿\mathrm{\Δ\Φ}}_{i1,j1,k1,m1}-{\▿\mathrm{\ΔN}}_{i1,j1,k1,m1}\·{\mathrm{\λ}}_{i1,j1,k1,m1})---\left(16\right)$

$-\frac{f_3}{f_2-f_3}({\▿\mathrm{\Δ\Φ}}_{i2,j2,k2,m2}-{\▿\mathrm{\ΔN}}_{i2,j2,k2,m2}\·{\mathrm{\λ}}_{i2,j2,k2,m2})$

$\frac{\▿\mathrm{\ΔK}}{f_1^2}=\frac{f_2{f}_3}{f_1(f_2-f_3)}[({\▿\mathrm{\Δ\Φ}}_{i1,j1,k1,m1}-{\▿\mathrm{\ΔN}}_{i1,j1,k1,m1}\·{\mathrm{\λ}}_{i1,j1,k1,m1})---\left(17\right)$

$-({\▿\mathrm{\Δ\Φ}}_{i2,j2,k2,m2}-{\▿\mathrm{\ΔN}}_{i2,j2,k2,m2}\·{\mathrm{\λ}}_{i2,j2,k2,m2})]$

In formula,

represent deion layer pseudorange,

the two poor ionosphere delay that represents B1 frequency, (i1, j1, k1, m1) and (i2, j2, k2, m2) is carrier combination coefficient.

Step S103, the two poor ionosphere delay according to deion layer pseudorange and B1 frequency, calculates two blur leveles with the 4th frequency dependence.As shown in Figure 3, detailed process is as follows:

1, the combined carriers double difference of calculating and the 4th frequency dependence, equation is:

${\▿\mathrm{\Δ\Φ}}_{i,j,k,m}=\▿\mathrm{\Δ\ρ}-{\mathrm{\β}}_{i,j,k,m}\·\frac{\▿\mathrm{\ΔK}}{f_1^2}+{\▿\mathrm{\ΔN}}_{i,j,k,m}{\mathrm{\λ}}_{i,j,k,m}+{\▿\mathrm{\Δ\ϵ}}_{{\mathrm{\Φ}}_{i,j,k,m}}---\left(18\right)$

In formula, (i, j, k, m) is integer, and m ≠ 0;

2, the blur level of calculating and the 4th frequency dependence:

By deion layer pseudorange

two poor ionosphere delay with B1 frequency

substitution formula (18), obtains blur level

${\▿\mathrm{\ΔN}}_{i,j,k,m}=\mathrm{int}[\frac{{\▿\mathrm{\Δ\Φ}}_{i,j,k,m}-\▿\mathrm{\Δ\ρ}}{{\mathrm{\λ}}_{i,j,k,m}}+\frac{{\mathrm{\β}}_{i,j,k,m}}{{\mathrm{\λ}}_{i,j,k,m}}\·\frac{\▿\mathrm{\ΔK}}{f_1^2}+{\mathrm{\ϵ}}_{{\▿\mathrm{\ΔN}}_{i,j,k,m}}]---\left(19\right)$

In formula,

for blur level random noise;

3, smoothing processing, is about to blur level

carry out the smoothing processing of 2～3 minutes, can obtain reliably

In this method, select carrier combination coefficient (0,0 ,-1,1) and (1,0 ,-6,6), calculate the blur level with the 4th frequency dependence

Step S104, four blur leveles that calculate according to above-mentioned steps are calculated the Big Dipper four independent blur level of carrier wave frequently.Utilize four blur leveles that calculated with

according to formula (20)～(23), calculate respectively the independent blur level of B1, B2, B3, each carrier wave of S

with

$\▿\mathrm{\Δ}{N}_1=6{\▿\mathrm{\ΔN}}_{\mathrm{0,0},-\mathrm{1,1}}-{\▿\mathrm{\ΔN}}_{-\mathrm{1,0},-\mathrm{6,6}}---\left(20\right)$

${\▿\mathrm{\ΔN}}_2={\▿\mathrm{\ΔN}}_1-{\▿\mathrm{\ΔN}}_{1,-\mathrm{1,0,0}}---\left(21\right)$

${\▿\mathrm{\ΔN}}_3={\▿\mathrm{\ΔN}}_1-{\▿\mathrm{\ΔN}}_{\mathrm{1,0},-\mathrm{1,0}}---\left(22\right)$

${\▿\mathrm{\ΔN}}_4=7\▿\mathrm{\Δ}{N}_{\mathrm{0,0},-\mathrm{1,1}}-({\▿\mathrm{\ΔN}}_{-\mathrm{1,0},-\mathrm{6,6}}+{\▿\mathrm{\ΔN}}_{\mathrm{1,0},-\mathrm{1,0}}).---\left(23\right)$

Four frequency solution of fuzzy degree evaluation times depend primarily on the blur level of the 4th frequency dependence fixes time really.And in three frequency situations, solution of fuzzy degree evaluation time depends primarily on the resolving time of the 3rd independent blur level.Carrier phase measurement noise is got 2% week, and in four frequency situations, the mean square deviation of the blur level of the 4th frequency dependence is 2.17 weeks; In three frequency situations, the mean square deviation of the 3rd independent blur level is 12.683 weeks.Therefore, four frequency solution of fuzzy degree evaluation times will only have 1/36 of three frequency solution of fuzzy degree evaluation times.

By above technical scheme, can obtain drawing a conclusion: under middle long base line condition, use the method for describing in the present invention to carry out ambiguity resolution, utilize the Big Dipper four observed quantities frequently just can be successfully in several minutes fixing blur level, greatly shorten the resolving time of blur level, improved the power that is fixed into of blur level.

Above embodiment is only for illustrating the present invention; and be not limitation of the present invention; the those of ordinary skill in relevant technologies field; without departing from the spirit and scope of the present invention; can also make a variety of changes and modification; therefore all technical schemes that are equal to also belong to category of the present invention, and scope of patent protection of the present invention should be defined by the claims.

Claims (2)

1. the middle long baseline Ambiguity Solution Methods based on the Big Dipper four frequency signals, is characterized in that, comprises the following steps:

S1: utilize four frequency combined pseudoranges and four frequency combined carriers to calculate two wide lane ambiguities;

S2: utilize double difference and the corresponding blur level of Liang Gekuan lane carrier phase, calculate the two poor ionosphere delay of deion layer pseudorange and B1 frequency;

S3: the two poor ionosphere delay according to deion layer pseudorange and B1 frequency, calculates two blur leveles with the 4th frequency dependence;

S4: four blur leveles that calculate according to S1～S3 are calculated the Big Dipper four independent blur level of carrier wave frequently;

Described step S1 specifically comprises:

S1.1: construct four frequency combined pseudoranges and four combined carriers frequently;

The observation equation of Big Dipper pseudorange, carrier phase is respectively:

$P_i=\mathrm{\ρ}(t_s,t_r)+C({\mathrm{dt}}_r-{\mathrm{dt}}_s)+d_{\mathrm{orb}}+d_{\mathrm{trop}}+\frac{K}{{f_i}^2}+M_{\mathrm{Pi}}+{\mathrm{\ϵ}}_{\mathrm{Pi}}---\left(1\right)$

In formula, subscript i represents carrier wave B _iwith S relevant parameter, i=1,2,3; P _ifor carrier wave B _iwith the corresponding pseudo range observed quantity of S, unit is rice;

be respectively carrier wave B _ibe respectively rice, week with the phase observations Liang， unit of S; λ _ifor carrier wave B _iwith the wavelength of S, unit is rice; N _ifor carrier wave B _iwith the integer ambiguity of S, unit is week; Dt _s, dt _rbe respectively satellite clock correction, receiver clock correction, unit is second; C is the light velocity, and unit is meter per second;

for carrier wave B _iwith the corresponding ionosphere delay of S, unit is rice; f _ifor carrier wave B _iwith the frequency of S, unit is hertz; d _tropfor tropospheric retardation, unit is rice; M _pi, M _{Φ i}be respectively B _iwith the multipath effect of pseudorange, carrier phase on S frequency, unit is rice; ε _pi, ε _{Φ i}be respectively the observation noise of pseudorange, carrier phase, unit is rice; ρ be satellite to the geometric distance of receiver antenna, unit be rice;

Yi Zhouwei unit, the general type of four frequency combined carriers is:

Yi meter Wei unit, the general type of four frequency combined carriers is:

${\mathrm{\Φ}}_{i,j,k,m}=\frac{i\·f_1\·{\mathrm{\Φ}}_1+j\·f_2\·{\mathrm{\Φ}}_2+k\·f_3\·{\mathrm{\Φ}}_3+m\·f_4\·{\mathrm{\Φ}}_4}{i\·f_1+j\·f_2+k\·f_3+m\·f_4}---\left(4\right)$

The blur level of combined carriers, frequency and wavelength are respectively:

N _i,j,k,m=iN ₁+jN ₂+kN ₃+mN ₄ （5）

f _i,j,k,m=if ₁+jf ₂+kf ₃+mf ₄ （6）

${\mathrm{\λ}}_{i,j,k,m}=\frac{C}{f_{i,j,k}}=\frac{{\mathrm{\λ}}_1{\mathrm{\λ}}_2{\mathrm{\λ}}_3{\mathrm{\λ}}_4}{i\·{\mathrm{\λ}}_2{\mathrm{\λ}}_3{\mathrm{\λ}}_4+j\·{\mathrm{\λ}}_1{\mathrm{\λ}}_3{\mathrm{\λ}}_4+k{\mathrm{\λ}}_1{\mathrm{\λ}}_2{\mathrm{\λ}}_4+m{\mathrm{\λ}}_1{\mathrm{\λ}}_2{\mathrm{\λ}}_3}---\left(7\right)$

The general type of four frequency combined pseudoranges is:

$P_{a,b,c,d}=\frac{a\·f_1\·P_1+b\·f_2\·P_2+c\·f_3\·P_3+d\·f_4\·P_4}{a\·f_1+b\·f_2+c\·f_3+d\·f_4}---\left(8\right)$

Four frequency combined pseudoranges and the four frequently observation equation of combined carriers are expressed as:

$P_{a,b,c,d}=\mathrm{\ρ}+C({\mathrm{dt}}_r-{\mathrm{dt}}_s)+d_{\mathrm{orb}}+d_{\mathrm{trop}}+{\mathrm{\β}}_{a,b,c,d}\·\frac{K}{{f_1}^2}+{\mathrm{\ϵ}}_{P_{a,b,c,d}}---\left(9\right)$

（10）

In formula,

for B1 frequency ionosphere delay, β _{a, b, c, d}and β _{i, j, k, m}be respectively the ionosphere coefficient of combined pseudorange, combined carriers:

${\mathrm{\β}}_{a,b,c,d}=(\frac{a}{f_1}+\frac{b}{f_2}+\frac{c}{f_3}+\frac{d}{f_4})\·\frac{{f_1}^2}{f_{a,b,c,d}}---\left(11\right)$

${\mathrm{\β}}_{i,j,k,m}=(\frac{i}{f_1}+\frac{j}{f_2}+\frac{k}{f_3}+\frac{m}{f_4})\·\frac{{f_1}^2}{f_{i,j,k,m}}---\left(12\right)$

with

be respectively the observation noise of combined pseudorange, combined carriers;

According to pseudorange combination coefficient (a, b, c, d) and carrier combination coefficient (i, j, k, m), calculate four frequency combined pseudoranges and four combined carriers frequently;

S1.2: the double difference of tectonic association pseudorange and combined carriers, equation is as follows:

$\▿\mathrm{\Δ}{P}_{a,b,c,d}=\▿\mathrm{\Δ\ρ}(t_s,t_r)+\▿\mathrm{\Δ}{d}_{\mathrm{orb}}+\▿\mathrm{\Δ}{d}_{\mathrm{trop}}+{\mathrm{\β}}_{a,b,c,d}\·\frac{\▿\mathrm{\ΔK}}{{f_1}^2}+\▿\mathrm{\Δ}{M}_P+\▿\mathrm{\Δ}{\mathrm{\ϵ}}_{P_{a,b,c,d}}$

（13）

S1.3: utilize the double difference of combined pseudorange and combined carriers to calculate wide lane ambiguity, computing formula is:

$\▿\mathrm{\Δ}{N}_{i,j,k,m}=\mathrm{int}[\frac{\▿\mathrm{\Δ}{\mathrm{\Φ}}_{i,j,k,m}-\▿\mathrm{\Δ}{P}_{a,b,c,d}}{{\mathrm{\λ}}_{i,j,k,m}}+\frac{{\mathrm{\β}}_{i,j,k,m}+{\mathrm{\β}}_{a,b,c,d}}{{\mathrm{\λ}}_{i,j,k,m}}\·\frac{\▿\mathrm{\ΔK}}{{f_1}^2}-\frac{\▿\mathrm{\Δ}{\mathrm{\ϵ}}_{{\mathrm{\Φ}}_{i,j,k,m}}-\▿\mathrm{\Δ}{\mathrm{\ϵ}}_{P_{a,b,c,d}}}{{\mathrm{\λ}}_{i,j,k,m}}]$

（15）

In formula,

represent two poor operators, int[] represent to round up;

In step S1, adopt combined pseudorange and combined carriers

calculate wide lane ambiguity , adopt combined pseudorange

and combined carriers

calculate wide lane ambiguity

The formula of two poor ionosphere delays that calculates deion layer pseudorange and B1 frequency in described step S2 is as follows:

$\▿\mathrm{\Δ\ρ}=\frac{f_2}{f_2-f_3}(\▿\mathrm{\Δ}{\mathrm{\Φ}}_{i1,j1,k1,m1}-\▿\mathrm{\Δ}{N}_{i1,j1,k1,m1}\·{\mathrm{\λ}}_{i1,j1,k1,m1})---\left(16\right)$ $-\frac{f_3}{f_2-f_3}(\▿\mathrm{\Δ}{\mathrm{\Φ}}_{i2,j2,k2,m2}-\▿\mathrm{\Δ}{N}_{i2,j2,k2,m2}\·{\mathrm{\λ}}_{i2,j2,k2,m2})$

$\frac{\▿\mathrm{\ΔK}}{{f_1}^2}=\frac{f_2{f}_3}{f_1(f_2-f_3)}[(\▿\mathrm{\Δ}{\mathrm{\Φ}}_{i1,j1,k1,m1}-\▿\mathrm{\Δ}{N}_{i1,j1,k1,m1}\·{\mathrm{\λ}}_{i1,j1,k1,m1})---\left(17\right)$

$-(\▿\mathrm{\Δ}{\mathrm{\Φ}}_{i2,j2,k2,m2}-\▿\mathrm{\Δ}{N}_{i2,j2,k2,m2}\·{\mathrm{\λ}}_{i2,j2,k2,m2})]$

In formula,

represent deion layer pseudorange,

the two poor ionosphere delay that represents B1 frequency, (i1, j1, k1, m1) and (i2, j2, k2, m2) is carrier combination coefficient;

Described step S3 specifically comprises:

S3.1: the combined carriers double difference of calculating and the 4th frequency dependence, equation is:

$\▿\mathrm{\Δ}{\mathrm{\Φ}}_{i,j,k,m}=\▿\mathrm{\Δ\ρ}-{\mathrm{\β}}_{i,j,k,m}\·\frac{\▿\mathrm{\ΔK}}{{f_1}^2}+\▿\mathrm{\Δ}{N}_{i,j,k,m}{\mathrm{\λ}}_{i,j,k,m}\▿\mathrm{\Δ}{\mathrm{\ϵ}}_{{\mathrm{\Φ}}_{i,j,k,m}}---\left(18\right)$

In formula, (i, j, k, m) is integer, and m ≠ 0;

S3.2: calculate the blur level with the 4th frequency dependence:

By deion layer pseudorange

two poor ionosphere delay with B1 frequency

substitution formula (18), obtains blur level

$\▿\mathrm{\Δ}{N}_{i,j,k,m}=\mathrm{int}[\frac{\▿\mathrm{\Δ}{\mathrm{\Φ}}_{i,j,k,m}-\▿\mathrm{\Δ\ρ}}{{\mathrm{\λ}}_{i,j,k,m}}+\frac{{\mathrm{\β}}_{i,j,k,m}}{{\mathrm{\λ}}_{i,j,k,m}}\·\frac{\▿\mathrm{\ΔK}}{{f_1}^2}+{\mathrm{\ϵ}}_{{\▿\mathrm{\ΔN}}_{i,j,k,m}}]---\left(19\right)$

In formula,

for blur level random noise;

S3.3: smoothing processing, by blur level

carry out the smoothing processing of 2～3 minutes, can obtain reliably

In step S3, select carrier combination coefficient (0,0 ,-1,1) and (1,0 ,-6,6), calculate the blur level with the 4th frequency dependence

,

2. the middle long baseline Ambiguity Solution Methods based on the Big Dipper four frequency signals as claimed in claim 1, is characterized in that, the mode that described step S4 calculates the independent blur level of the Big Dipper four frequency carrier waves is:

Utilize four blur leveles that calculated

,

,

with

, according to formula (20)～(23), calculate respectively the independent blur level of B1, B2, B3, each carrier wave of S

with

$\▿\mathrm{\Δ}{N}_1=6\▿\mathrm{\Δ}{N}_{\mathrm{0,0},-\mathrm{1,1}}-\▿\mathrm{\Δ}{N}_{-\mathrm{1,0},-\mathrm{6,6}}---\left(20\right)$

$\▿\mathrm{\Δ}{N}_2=\▿\mathrm{\Δ}{N}_1-\▿\mathrm{\Δ}{N}_{1,-\mathrm{1,0,0}}---\left(21\right)$

$\▿\mathrm{\Δ}{N}_3=\▿\mathrm{\Δ}{N}_1-\▿\mathrm{\Δ}{N}_{\mathrm{1,0},-\mathrm{1,0}}---\left(22\right)$

$\▿\mathrm{\Δ}{N}_4=7\▿\mathrm{\Δ}{N}_{\mathrm{0,0},-\mathrm{1,1}}-(\▿\mathrm{\Δ}{N}_{-\mathrm{1,0},-\mathrm{6,6}}+\▿\mathrm{\Δ}{N}_{\mathrm{1,0},-\mathrm{1,0}}).---\left(23\right)$

Images