CN105572702A - Sliding window loop tracking method and device - Google Patents

Abstract

The invention provides a sliding window loop tracking method and a device. According to the technical scheme of the invention, firstly, based on locally generated sine and cosine copied carriers, stripping the carrier of a satellite signal to obtain a first branch signal and a second branch signal; secondly, stripping the pseudo codes of the first and second branch signals according to local pseudo codes and conducting the low-pass filtering and the coherent integration to obtain the coherent integral values of a front branch, an immediate branch and a rear branch; thirdly, accumulating multiple adjacent integral values of the immediate branch in the non-coherent manner and conducting the phase demodulation of a carrier loop to obtain the phase difference between a local carrier and an input carrier; fourthly, adopting the non-coherent lead-lag magnitude method, estimating the integral values of the front and rear branches to obtain the phase difference between a local pseudo code and an input pseudo code; fifthly, filtering the phase difference between the local pseudo code and the input pseudo code, and adjusting the frequency of the local pseudo code according to the filtering result; sixthly, filtering the phase difference between the local carrier and the input carrier within a long non-coherent accumulation period of time in the sliding window manner, and adjusting the frequency of the sine copied carrier and the frequency of the cosine copied carrier according to the filtering result.

Description

A kind of moving window loop tracks method and device

Technical field

The present invention relates to satellite navigation application, be specifically related to a kind of moving window loop tracks method and apparatus based on noncoherent accumulation phase detector, can be used for high satellite-signal dynamically, under the environment of weak signal to follow the tracks of, the tracking accuracy of receiver to navigation satellite signal can be improved.

Background technology

Along with the growth requirement of national defense and military, dynamic (speed) of the advanced weaponry such as guided missile, opportunity of combat equipment is more and more higher, under high dynamic environment, owing to there being larger relative velocity, acceleration even acceleration between the receiver on guided missile, fighter plane etc. and satellite, this will cause larger Doppler shift and rate of change thereof.In addition, along with the development of the application of satellite navigation and the raising of up-to-dateness, the requirement for the tracking accuracy of receiver is also more and more higher.This makes conventional navigation receiver effectively can not process satellite-signal, thus cannot position and navigate, and need be improved it.Therefore, stable effective loop tracks method must be developed, make it adapt to high dynamic environment, have again higher tracking accuracy, effectively can realize the accurate location under high dynamic environment.

Summary of the invention

In view of this, the embodiment of the present invention provides a kind of moving window loop tracks method and apparatus, to realize the accurate location under high dynamic environment.

For achieving the above object, the embodiment of the present invention provides following technical scheme:

A kind of moving window loop tracks method, is applied in receiver, comprises:

Obtain satellite-signal;

Copy carrier signal and cosine according to the sine produced local in receiver to copy carrier signal and carry out carrier wave stripping to described satellite-signal, obtain the first tributary signal and the second tributary signal;

According to the pseudo-code that described receiver this locality is copied, peel off the pseudo-code on described first tributary signal and the second tributary signal;

Low-pass filtering and coherent integration are carried out to described first tributary signal after stripping pseudo-code and the second tributary signal, obtains and the coherent integration value in the coherent integration value on described first tributary signal and the corresponding front branch road of the second tributary signal, immediately branch road and the coherent integration value on rear branch road;

Adjacent multiple coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, and the result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier;

Adopt the incoherent integrated value subtracted in advance in dry integrated value and rear branch road that delayed amplitude method goes up mutually to described front branch road to estimate, obtain the phase differential between local pseudo-code and input pseudo-code;

Filtering is carried out to the phase differential between local pseudo-code and input pseudo-code;

Adopt the mode of moving window, within the long noncoherent accumulation time, filtering is carried out to the phase differential between described local carrier and incoming carrier;

Regulate local pseudo-code frequency according to through the phase differential between filtered described local pseudo-code and input pseudo-code, upgrade the local pseudo-code signal copied;

The frequency that carrier signal and cosine copy carrier signal is copied according to regulating sine through the phase differential between filtered described local carrier and incoming carrier.

Preferably, in above-mentioned moving window loop tracks method, described adjacent multiple coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier; Comprise:

Four times adjacent coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, and the result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier.

Preferably, in above-mentioned moving window loop tracks method, described adjacent multiple coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier; Comprise:

According to formula $\begin{array}{c}{D}_{PLL}=\frac{180}{\mathrm{\π}}\frac{-1}{\sqrt{{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|I_P\left(n\right)\right|\]}^2+{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\]}^2}}\·\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\\ \·\mathrm{sgn}\left\{\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\right|I_P\left(n\right)-Q_P\left(n\right)|-\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}|I_P\left(n\right)+Q_P\left(n\right)\left|\right\}\end{array}$ Calculate the phase differential between local carrier and incoming carrier, wherein, described I _pn () is the integrated value on instant branch road that the first tributary signal is corresponding, described in | Q _p(n) | be the integrated value on instant branch road that the second tributary signal is corresponding, described M is noncoherent accumulation number of times.

Preferably, in above-mentioned moving window loop tracks method, describedly copy carrier signal and cosine according to the sine produced local in receiver and copy carrier signal carrier wave stripping is carried out to described satellite-signal, obtain the first tributary signal and the second tributary signal, comprising:

Filtering and amplification are carried out to described satellite-signal;

The sinusoidal wave local oscillation signal that described satellite-signal after filtering and amplification and the local oscillator in receiver produce is carried out mixing, intermediate-freuqncy signal will be down-converted to through amplification and filtered satellite-signal;

Analog to digital conversion is carried out to described intermediate-freuqncy signal, obtains the digital intermediate frequency input signal of discrete time;

Described digital intermediate frequency input signal is copied carrier signal mixing with the sine produced local in receiver be multiplied, obtain the first tributary signal; By described digital intermediate frequency input signal and in receiver the local cosine produced copy carrier signal mixing and be multiplied and obtain the second tributary signal.

Preferably, in above-mentioned moving window loop tracks method, the described pseudo-code copied according to described receiver this locality, peel off the pseudo-code on described first tributary signal and the second tributary signal, comprising:

Respectively described first tributary signal is multiplied, to peel off the pseudo-code on described first tributary signal and the second tributary signal with the pseudo-code copied local in receiver with the second tributary signal.

A kind of moving window loop tracks device, comprising:

Signal receiver, for obtaining satellite-signal;

Processor, copies carrier signal and carries out carrier wave stripping for copying carrier signal and cosine according to the sine produced local in receiver to described satellite-signal, obtain the first tributary signal and the second tributary signal;

Code stripper, for the pseudo-code copied according to described receiver this locality, peels off the pseudo-code on described first tributary signal and the second tributary signal;

Integrator, for carrying out low-pass filtering and coherent integration to described first tributary signal after stripping pseudo-code and the second tributary signal, obtain and the coherent integration value in the coherent integration value on described first tributary signal and the corresponding front branch road of the second tributary signal, immediately branch road and the coherent integration value on rear branch road;

Carrier wave ring Discr., for the adjacent multiple coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier;

Code ring Discr., for adopting the incoherent integrated value subtracted in advance in dry integrated value and rear branch road that delayed amplitude method goes up mutually to described front branch road to estimate, obtains the phase differential between local pseudo-code and input pseudo-code;

Loop filter, for carrying out filtering to the phase differential between local pseudo-code and input pseudo-code;

Carrier wave ring wave filter, for adopting the mode of moving window, carries out filtering to the phase differential between described local carrier and incoming carrier within the long noncoherent accumulation time;

Yardage controlled oscillator, for according to the pseudo-code frequency regulating local pseudo-code generator to export through the phase differential between filtered described local pseudo-code and input pseudo-code, upgrades the local pseudo-code signal copied;

Carrier number controlled oscillator, for according to regulates sine to copy through the phase differential between filtered described local carrier and incoming carrier frequency that carrier signal and cosine copy carrier signal.

Preferably, in above-mentioned moving window loop tracks device, described carrier wave ring Discr., specifically for:

Four times adjacent coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, and the result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier.

Preferably, in above-mentioned moving window loop tracks device, described carrier wave ring Discr., specifically for:

According to formula $\begin{array}{c}{D}_{PLL}=\frac{180}{\mathrm{\π}}\frac{-1}{\sqrt{{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|I_P\left(n\right)\right|\]}^2+{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\]}^2}}\·\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\\ \·\mathrm{sgn}\left\{\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\right|I_P\left(n\right)-Q_P\left(n\right)|-\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}|I_P\left(n\right)+Q_P\left(n\right)\left|\right\}\end{array}$ Calculate the phase differential between local carrier and incoming carrier, wherein, described I _pn () is the integrated value on instant branch road that the first tributary signal is corresponding, described Q _pn () is the integrated value on instant branch road that the second tributary signal is corresponding, described M is noncoherent accumulation number of times.

Preferably, in above-mentioned moving window loop tracks device, described processor comprises:

Wave filter and amplifier, for carrying out filtering and amplification to satellite-signal;

Frequency mixer, carries out mixing for the sinusoidal wave local oscillation signal described satellite-signal after filtering and amplification and the local oscillator in receiver produced, will be down-converted to intermediate-freuqncy signal through amplification and filtered satellite-signal;

Analog to digital converter, for carrying out analog to digital conversion to described intermediate-freuqncy signal, obtains the digital intermediate frequency input signal of discrete time;

Carrier wave stripper, is multiplied for described digital intermediate frequency input signal is copied carrier signal mixing with the sine produced local in receiver, obtains the first tributary signal; By described digital intermediate frequency input signal and in receiver the local cosine produced copy carrier signal mixing and be multiplied and obtain the second tributary signal.

Preferably, in above-mentioned moving window loop tracks device, described code stripper, specifically for:

Respectively described first tributary signal is multiplied, to peel off the pseudo-code on described first tributary signal and the second tributary signal with the pseudo-code copied local in receiver with the second tributary signal.

Based on technique scheme, device disclosed in the above embodiments of the present application, proposes a kind of PLL loop phase detector based on noncoherent accumulation, can effectively improve loop tracks precision, improves Position location accuracy; Adopt, based on moving window carrier wave ring wave filter, filtering is carried out to the phase differential between local carrier and incoming carrier, shorten the loop update cycle, improve the performance of dynamic tracking of loop, enhance the dynamic tracking capabilities of receiver; Have higher dynamic adaptable, tracking accuracy is higher; Further, do not need the structure changing existing receiver, directly can utilize software simulating, cost is low, and reliability is high, and engineering applicability is strong, effectively can realize the accurate location under high dynamic environment.

Accompanying drawing explanation

In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, accompanying drawing in the following describes is only embodiments of the invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to the accompanying drawing provided.

The structural representation of Fig. 1 a kind of moving window loop tracks device disclosed in the embodiment of the present application;

Fig. 2 is moving window loop tracks device fundamental diagram disclosed in the embodiment of the present application;

Fig. 3 is the phase demodulation curve map of the PLL phase detector based on noncoherent accumulation;

Fig. 4 is the processing procedure schematic diagram of the carrier wave circle filtering processor based on moving window;

Fig. 5 is the concrete structure schematic diagram of described moving window loop tracks de-vice processor;

The schematic flow sheet of Fig. 6 a kind of moving window loop tracks disclosed in the embodiment of the present application.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, be clearly and completely described the technical scheme in the embodiment of the present invention, obviously, described embodiment is only the present invention's part embodiment, instead of whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtained under creative work prerequisite, belong to the scope of protection of the invention.

In conventional loop, in order to boostfiltering effect, reduce noise and improve tracking accuracy, coherent integration time should be extended as far as possible, but the length of coherent integration time is by the impact of navigation data bits saltus step.The D2 navigation message speed that such as B3I broadcasts is 500bps, and therefore the most long coherent integration times of loop can only be 2ms, therefore can not improve tracking accuracy further by increase coherent integration time.

According to the problems referred to above, in order to overcome the deficiencies in the prior art, the application provides a kind of moving window loop tracks method and apparatus based on noncoherent accumulation phase detector, the tenacious tracking of satellite-signal under high dynamic environment can be realized, tracking accuracy under effective raising high dynamic environment, provides effective pricise position service of high dynamic motion carrier.This technology can be generalized to field of satellite navigation, and utilize software to realize, cost is low, and improves the positioning precision of receiver, strengthens the navigator fix ability of receiver.

The structural representation of Fig. 1 a kind of moving window loop tracks device disclosed in the embodiment of the present application, Fig. 2 is the schematic diagram of moving window loop tracks device, and see Fig. 1 and Fig. 2, disclosed in the embodiment of the present application, method comprises:

Signal receiver 10, for obtaining satellite-signal;

The processor 20 be connected with described signal receiver 10, copy carrier signal for copying carrier signal and cosine according to the sine produced local in receiver carrier wave stripping is carried out to described satellite-signal, obtain the first tributary signal i (n) and the second tributary signal q (n);

The code stripper 30 be connected with described processor 20, for the pseudo-code copied according to described receiver this locality, peels off the pseudo-code q (n) on described first tributary signal i (n) and the second tributary signal;

The integrator 40 be connected with described code stripper 30, for carrying out low-pass filtering and coherent integration to described first tributary signal i (n) after stripping pseudo-code and the second tributary signal q (n), obtain the coherent integration value I on the front branch road corresponding with described first tributary signal i (n) and the second tributary signal q (n) _eand Q _e, the coherent integration value I on instant branch road _pand Q _p, and the coherent integration value I on rear branch road _land Q _l;

The carrier wave ring Discr. 50 be connected with described integrator 40, for the adjacent multiple coherent integration values on the instant branch road of described first tributary signal i (n) and the second tributary signal q (n) correspondence are carried out noncoherent accumulation, result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase difference between local carrier and incoming carrier _ewherein, the PLL loop phase detector based on noncoherent accumulation selected by described carrier wave ring Discr. 50, based on the PLL loop phase detector of described noncoherent accumulation, by carrying out noncoherent accumulation to adjacent coherent integration values multiple on instant branch road, then the result after noncoherent accumulation is carried out carrier wave ring phase demodulation, the phase difference between local carrier and incoming carrier can be obtained _e;

The code ring Discr. 60 be connected with described integrator 40, for adopting the incoherent integrated value subtracted in advance in dry integrated value and rear branch road that delayed amplitude method goes up mutually to described front branch road to estimate, obtains the phase differential δ between local pseudo-code and input pseudo-code _cp;

The Loop filter 70 be connected with described code ring Discr. 60, for local pseudo-code and input pseudo-code between phase differential δ _cpcarry out filtering;

The carrier wave ring wave filter 80 be connected with described carrier wave ring Discr. 50, described carrier wave ring wave filter 80 is the carrier wave ring wave filter based on moving window, for adopting the mode of moving window, to the phase difference between described local carrier and incoming carrier within the long noncoherent accumulation time _ecarry out filtering, by utilizing based on the carrier wave ring wave filter of moving window described phase difference _ecarry out filtering, solve the problem of Doppler's change in during cannot meeting tracking when filtering renewal rate declines, by the mode of moving window, within the long noncoherent accumulation time, do repeatedly PLL loop filtering, shorten the loop update cycle, improve the performance of dynamic tracking of loop;

The yardage controlled oscillator 90 be connected with described Loop filter 70, for the pseudo-code frequency that foundation regulates local pseudo-code generator to export through the phase differential between filtered described local pseudo-code and input pseudo-code, upgrade the local pseudo-code signal copied, input to described code stripper 30, this device forms closed-loop, thus ensures that the local pseudo-code signal copied is consistent with Received signal strength;

The carrier number controlled oscillator 100 be connected with described carrier wave ring wave filter 80, for according to regulates sine to copy through the phase differential between filtered described local carrier and incoming carrier frequency that carrier signal and cosine copy carrier signal, input to described processor 20, make this device form closed-loop, thus ensure that local replica carrier signal is consistent with Received signal strength.

In conventional solution, add long coherent integration times, be equivalent to noise bandwidth narrow, thus effectively improve processing gain, but the length of coherent integration time is by the impact of navigation data bits saltus step, under navigation message speed is 500bps situation, loop coherent integration time is the longest can only be 2ms, single correlated results signal to noise ratio (S/N ratio) is too low, and convention carrier phase demodulation algorithm operation irregularity, coherent integration time shorter in addition limits the raising of tracking accuracy.

Be directed to this, the present invention proposes the PLL loop phase detector by adopting based on non-coherent accumulation, after coherent accumulation, improving processing gain further by carrying out noncoherent accumulation to the result of coherent accumulation, having broken away from the saltus step of navigation message data bit to the restriction of accumulated time length.

Wherein, the PLL loop phase detector based on non-coherent accumulation is insensitive to 180 ° of carrier wave phase transformations caused by data bit saltus step, and it leads into scope is [-90 °, 90 °].

And the described PLL loop phase detector form based on non-coherent accumulation is simple, does not need to change existing receiver structure, only need to revise the carrier wave phase detector form in conventional loop, engineering applicability is high.

Be directed in traditional scheme, under high dynamic environment, the speed that carrier is higher, acceleration and acceleration cause reception carrier to produce larger Doppler frequency and frequency displacement rate of change.When utilizing conventional loop to follow the tracks of, receiver dynamic tracking capabilities and tracking accuracy contradiction each other.In order to solve this contradiction, the present invention proposes on the basis of the PLL loop phase detector based on non-coherent accumulation, adopts the carrier wave ring wave filter based on moving window.By on the basis of coherent accumulation, increase the noncoherent accumulation time, utilize the carrier wave ring wave filter based on moving window to solve the problem of Doppler's change in during conventional loop cannot meet tracking when filtering renewal rate declines simultaneously.

Therefore, above-mentioned moving window loop tracks device, by the mode of moving window, does repeatedly PLL loop phase demodulation, filtering within the long noncoherent accumulation time, shortens the loop update cycle, improves the performance of dynamic tracking of loop.Both remain noncoherent accumulation to the useful effect reducing noise and raising tracking accuracy, overcome again the impact of long-time loop renewal on track loop dynamic adaptable.Under high dynamic environment, there are higher tracking accuracy and loop tracks stability.

To sum up, device disclosed in the above embodiments of the present application, for under high navigation message rate behavior, coherent integration duration is limited, thus cause that tracking accuracy is poor, positioning result is inaccurate, propose a kind of PLL loop phase detector based on noncoherent accumulation, can imitate and improve loop tracks precision, improve Position location accuracy; Adopt based on moving window carrier wave ring wave filter the phase difference between local carrier and incoming carrier _ecarry out filtering, shorten the loop update cycle, improve the performance of dynamic tracking of loop, enhance the dynamic tracking capabilities of receiver; Have higher dynamic adaptable, tracking accuracy is higher; Further, do not need the structure changing existing receiver, directly can utilize software simulating, cost is low, and reliability is high, and engineering applicability is strong.

When disclosed in above-described embodiment, moving window loop tracks application of installation is in receiver, the PLL phase detector based on noncoherent accumulation is utilized to further increase signal to noise ratio (S/N ratio) and tracking accuracy on the one hand, utilize the carrier wave ring wave filter based on moving window to overcome the impact of longer update time on loop dynamic tracking performance on the other hand, improve the adaptability of loop under high dynamic environment.

In conventional loop, in order to boostfiltering effect, reduce noise and improve tracking accuracy, coherent integration time should be extended as far as possible, but the length of coherent integration time is by the impact of navigation data bits saltus step.The D2 navigation message speed that such as B3I broadcasts is 500bps, and therefore the most long coherent integration times of loop can only be 2ms, can not improve tracking accuracy further by increase coherent integration time.And above-mentioned moving window loop tracks device proposes a kind of PLL loop phase detector based on noncoherent accumulation, when 2ms coherent integration, add noncoherent accumulation, solve single correlated results signal to noise ratio (S/N ratio) too low, the problem of convention carrier phase demodulation algorithm operation irregularity.

Under high dynamic environment, usually comprise very large Doppler shift and rate of change thereof in the signal that receiver receives, along with the increase of noncoherent accumulation time, filtering renewal rate declines thereupon, thus during cannot tracking being met in the change of Doppler, and then cause loop tracks failure.Above-mentioned moving window loop tracks device introduces sliding-window filtering device on the basis of the PLL loop phase detector based on noncoherent accumulation, within the noncoherent accumulation time, overlap does repeatedly PLL loop phase demodulation, filtering, shorten the loop update cycle, improve the performance of dynamic tracking of loop under high dynamic environment.

Above-mentioned moving window loop tracks device, has more superior loop tracks performance in the applied environment of dynamic at height, low carrier-to-noise ratio.Both under having solved the shorter situation of coherent integration time, single correlated results signal to noise ratio (S/N ratio) was too low, the problem of tracking accuracy deficiency, which in turn improved the dynamic adaptable of loop under high dynamic environment.

Described carrier wave ring Discr. 50 can be specifically for: by described first tributary signal I _p(n) and the second tributary signal Q _pon n instant branch road that () is corresponding, four times adjacent coherent integration values carry out noncoherent accumulation, and the result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier.

Be understandable that, in described moving window loop tracks device disclosed in the above embodiments of the present application, when described carrier wave ring Discr. 50 is the PLL loop phase detector based on described noncoherent accumulation, specifically for foundation formula $\begin{array}{c}{D}_{PLL}=\frac{180}{\mathrm{\π}}\frac{-1}{\sqrt{{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|I_P\left(n\right)\right|\]}^2+{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\]}^2}}\·\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\\ \·\mathrm{sgn}\left\{\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\right|I_P\left(n\right)-Q_P\left(n\right)|-\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}|I_P\left(n\right)+Q_P\left(n\right)\left|\right\}\end{array}$ (formula 1) calculates the phase differential between local carrier and incoming carrier, wherein, and described I _pn () is the integrated value on instant branch road that the first tributary signal is corresponding, described Q _pn () is the integrated value on instant branch road that the second tributary signal is corresponding, described M is noncoherent accumulation number of times.

Wherein, the described PLL loop phase detector brief analysis based on described noncoherent accumulation is as follows:

Integrated value I on the instant branch road that one tributary signal is corresponding _p(n) ≈ A (n) R (ε) cos (θ ₀) (formula 2);

Integrated value Q on the instant branch road that second tributary signal is corresponding _p(n) ≈ A (n) R (ε) sin (θ ₀) (formula 3);

Bring formula 2 and 3 into described formula 1 can obtain:

$D_{PLL}\≈-\frac{180}{\mathrm{\π}}\left|\sin \left({\mathrm{\θ}}_0\right)\right|\·\mathrm{sgn}\left\{\right|cos\left({\mathrm{\θ}}_0\right)-\sin \left({\mathrm{\θ}}_0\right)|-|cos({\mathrm{\θ}}_0+\sin ({\mathrm{\θ}}_0)\left|\right\}$ (formula 4).

Based on the PLL phase detector of noncoherent accumulation phase demodulation curve as shown in Figure 3.

Be understandable that, under overcoming high dynamic environment, the larger Doppler that receiver high-speed motion brings and frequency displacement thereof, on the basis of the PLL phase detector based on described noncoherent accumulation, introduce the carrier wave ring wave filter based on moving window.The concrete processing procedure of the described carrier wave ring wave filter based on moving window as shown in Figure 4, Figure 4 shows that 4ms noncoherent accumulation, 2ms filtering upgrades, and noncoherent accumulation number of times concrete in engineering practice and filtering all can carry out suitable selection according to actual conditions update time.

As shown in Figure 4, noncoherent accumulation is carried out to the related data of adjacent 4ms, the PLL phase demodulation based on noncoherent accumulation is carried out to the result after cumulative, finally carries out filtering again., then carry out noncoherent accumulation next time, phase demodulation and filtering then.Related data between adjacent twice noncoherent accumulation has the overlap of 2ms, and actual filtering update time is 2ms thus, shortens the loop update cycle, improves loop dynamic tracking performance.

Therefore, the disclosed dynamic window loop tracks device of the above embodiments of the present application, had both remained the effective raising of noncoherent accumulation to tracking accuracy, overcame again long-time update time interval to the impact of loop dynamic tracking performance.

See Fig. 5, described processor 20 specifically can comprise:

Wave filter 21 and amplifier 22, for carrying out filtering and amplification to satellite-signal;

Frequency mixer 23, carries out mixing for the sinusoidal wave local oscillation signal described satellite-signal after filtering and amplification and the local oscillator in receiver produced, will be down-converted to intermediate-freuqncy signal through amplification and filtered satellite-signal;

Analog to digital converter 24, for carrying out analog to digital conversion to described intermediate-freuqncy signal, obtains the digital intermediate frequency input signal of discrete time;

Carrier wave stripper 25, is multiplied for described digital intermediate frequency input signal is copied carrier signal mixing with the sine produced local in receiver, obtains the first tributary signal; By described digital intermediate frequency input signal and in receiver the local cosine produced copy carrier signal mixing and be multiplied and obtain the second tributary signal.

Described code stripper 30, specifically for:

Respectively described first tributary signal i (n) is multiplied with the pseudo-code copied local in receiver with the second tributary signal q (n), to peel off the pseudo-code on described first tributary signal i (n) and the second tributary signal q (n).

The schematic flow sheet of Fig. 1 a kind of moving window loop tracks method in receiver disclosed in the embodiment of the present application, see Fig. 1, disclosed in the embodiment of the present application, method comprises:

Step S101: after getting satellite-signal, performs step S102;

Step S102: copy carrier signal and cosine according to the sine produced local in receiver and copy carrier signal carrier wave stripping is carried out to described satellite-signal, obtain the first tributary signal and the second tributary signal, perform step S103;

Step S103: the pseudo-code copied according to described receiver this locality, peels off the pseudo-code q (n) on described first tributary signal i (n) and the second tributary signal, performs step S104;

Step S104: with the second tributary signal q (n), low-pass filtering and coherent integration are carried out to described first tributary signal i (n) after peeling off pseudo-code, obtains the coherent integration value I on the front branch road corresponding with described first tributary signal i (n) and the second tributary signal q (n) _eand Q _e, the coherent integration value I on instant branch road _pand Q _p, and the coherent integration value I on rear branch road _land Q _l, perform step S105 and step S108;

Step S105: the adjacent multiple coherent integration value I on the instant branch road corresponding with the second tributary signal q (n) by described first tributary signal i (n) _pand Q _pcarry out noncoherent accumulation, the result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase difference between local carrier and incoming carrier _e, perform step S106;

Step S106: the mode adopting moving window, carries out filtering to the phase differential between described local carrier and incoming carrier within the long noncoherent accumulation time, performs step S107;

Step S107: copy the frequency that carrier signal and cosine copy carrier signal according to regulating sine through the phase differential between filtered described local carrier and incoming carrier;

Step S108: adopt the incoherent integrated value subtracted in advance in dry integrated value and rear branch road that delayed amplitude method goes up mutually to described front branch road to estimate, obtain the phase differential δ between local pseudo-code and input pseudo-code _cp, perform step S109;

Step S109: filtering is carried out to the phase differential between local pseudo-code and input pseudo-code, performs step S110;

Step S110: regulate local pseudo-code frequency according to through the phase differential between filtered described local pseudo-code and input pseudo-code, upgrades the local pseudo-code signal copied.

Corresponding with said apparatus, described step S105 specifically can comprise:

Four times adjacent coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, and the result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier.

Corresponding with said apparatus, described step S105 specifically can comprise:

According to formula $\begin{array}{c}{D}_{PLL}=\frac{180}{\mathrm{\π}}\frac{-1}{\sqrt{{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|I_P\left(n\right)\right|\]}^2+{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\]}^2}}\·\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\\ \·\mathrm{sgn}\left\{\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\right|I_P\left(n\right)-Q_P\left(n\right)|-\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}|I_P\left(n\right)+Q_P\left(n\right)\left|\right\}\end{array}$ Calculate the phase differential between local carrier and incoming carrier, wherein, described I _pn () is the integrated value on instant branch road that the first tributary signal is corresponding, described in | Q _p(n) | be the integrated value on instant branch road that the second tributary signal is corresponding, described M is noncoherent accumulation number of times.

Corresponding with said apparatus, described step S102 specifically can comprise:

Filtering and amplification are carried out to described satellite-signal;

The sinusoidal wave local oscillation signal that described satellite-signal after filtering and amplification and the local oscillator in receiver produce is carried out mixing, intermediate-freuqncy signal will be down-converted to through amplification and filtered satellite-signal;

Analog to digital conversion is carried out to described intermediate-freuqncy signal, obtains the digital intermediate frequency input signal of discrete time;

Described digital intermediate frequency input signal is copied carrier signal mixing with the sine produced local in receiver be multiplied, obtain the first tributary signal; By described digital intermediate frequency input signal and in receiver the local cosine produced copy carrier signal mixing and be multiplied and obtain the second tributary signal.

Corresponding with said apparatus, described step S103 specifically can comprise:

Respectively described first tributary signal is multiplied, to peel off the pseudo-code on described first tributary signal and the second tributary signal with the pseudo-code copied local in receiver with the second tributary signal.

In this instructions, each embodiment adopts the mode of going forward one by one to describe, and what each embodiment stressed is the difference with other embodiments, between each embodiment identical similar portion mutually see.For method disclosed in embodiment, because it is corresponding with device disclosed in embodiment, so description is fairly simple, relevant part illustrates see device section.

To the above-mentioned explanation of the disclosed embodiments, professional and technical personnel in the field are realized or uses the present invention.To be apparent for those skilled in the art to the multiple amendment of these embodiments, General Principle as defined herein can without departing from the spirit or scope of the present invention, realize in other embodiments.Therefore, the present invention can not be restricted to these embodiments shown in this article, but will meet the widest scope consistent with principle disclosed herein and features of novelty.

Claims (10)

1. a moving window loop tracks method, is applied in receiver, it is characterized in that, comprising:

Obtain satellite-signal;

Copy carrier signal and cosine according to the sine produced local in receiver to copy carrier signal and carry out carrier wave stripping to described satellite-signal, obtain the first tributary signal and the second tributary signal;

According to the pseudo-code that described receiver this locality is copied, peel off the pseudo-code on described first tributary signal and the second tributary signal;

Low-pass filtering and coherent integration are carried out to described first tributary signal after stripping pseudo-code and the second tributary signal, obtains and the coherent integration value in the coherent integration value on described first tributary signal and the corresponding front branch road of the second tributary signal, immediately branch road and the coherent integration value on rear branch road;

Adjacent multiple coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, and the result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier;

Adopt the incoherent integrated value subtracted in advance in dry integrated value and rear branch road that delayed amplitude method goes up mutually to described front branch road to estimate, obtain the phase differential between local pseudo-code and input pseudo-code;

Filtering is carried out to the phase differential between local pseudo-code and input pseudo-code;

Adopt the mode of moving window, within the long noncoherent accumulation time, filtering is carried out to the phase differential between described local carrier and incoming carrier;

Regulate local pseudo-code frequency according to through the phase differential between filtered described local pseudo-code and input pseudo-code, upgrade the local pseudo-code signal copied;

The frequency that carrier signal and cosine copy carrier signal is copied according to regulating sine through the phase differential between filtered described local carrier and incoming carrier.

2. moving window loop tracks method according to claim 1, it is characterized in that, described adjacent multiple coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier; Comprise:

Four times adjacent coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, and the result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier.

3. moving window loop tracks method according to claim 1, it is characterized in that, described adjacent multiple coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier; Comprise:

According to formula $\begin{array}{c}{D}_{PLL}=\frac{180}{\mathrm{\π}}\frac{-1}{\sqrt{{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|I_P\left(n\right)\right|\]}^2+{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\]}^2}}\·\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\\ \·\mathrm{sgn}\left\{\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}|I_P\left(n\right)-Q_P\left(n\right)|-\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}|I_P\left(n\right)+Q_P\left(n\right)|\right\}\end{array}$ Calculate the phase differential between local carrier and incoming carrier, wherein, described I _pn () is the integrated value on instant branch road that the first tributary signal is corresponding, described in | Q _p(n) | be the integrated value on instant branch road that the second tributary signal is corresponding, described M is noncoherent accumulation number of times.

4. moving window loop tracks method according to claim 1, it is characterized in that, describedly copy carrier signal and cosine according to the sine produced local in receiver and copy carrier signal carrier wave stripping is carried out to described satellite-signal, obtain the first tributary signal and the second tributary signal, comprising:

Filtering and amplification are carried out to described satellite-signal;

The sinusoidal wave local oscillation signal that described satellite-signal after filtering and amplification and the local oscillator in receiver produce is carried out mixing, intermediate-freuqncy signal will be down-converted to through amplification and filtered satellite-signal;

Analog to digital conversion is carried out to described intermediate-freuqncy signal, obtains the digital intermediate frequency input signal of discrete time;

Described digital intermediate frequency input signal is copied carrier signal mixing with the sine produced local in receiver be multiplied, obtain the first tributary signal; By described digital intermediate frequency input signal and in receiver the local cosine produced copy carrier signal mixing and be multiplied and obtain the second tributary signal.

5. moving window loop tracks method according to claim 1, is characterized in that, the described pseudo-code copied according to described receiver this locality, peels off the pseudo-code on described first tributary signal and the second tributary signal, comprising:

Respectively described first tributary signal is multiplied, to peel off the pseudo-code on described first tributary signal and the second tributary signal with the pseudo-code copied local in receiver with the second tributary signal.

6. a moving window loop tracks device, is characterized in that, comprising:

Signal receiver, for obtaining satellite-signal;

Processor, copies carrier signal and carries out carrier wave stripping for copying carrier signal and cosine according to the sine produced local in receiver to described satellite-signal, obtain the first tributary signal and the second tributary signal;

Code stripper, for the pseudo-code copied according to described receiver this locality, peels off the pseudo-code on described first tributary signal and the second tributary signal;

Integrator, for carrying out low-pass filtering and coherent integration to described first tributary signal after stripping pseudo-code and the second tributary signal, obtain and the coherent integration value in the coherent integration value on described first tributary signal and the corresponding front branch road of the second tributary signal, immediately branch road and the coherent integration value on rear branch road;

Carrier wave ring Discr., for the adjacent multiple coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier;

Code ring Discr., for adopting the incoherent integrated value subtracted in advance in dry integrated value and rear branch road that delayed amplitude method goes up mutually to described front branch road to estimate, obtains the phase differential between local pseudo-code and input pseudo-code;

Loop filter, for carrying out filtering to the phase differential between local pseudo-code and input pseudo-code;

Carrier wave ring wave filter, for adopting the mode of moving window, carries out filtering to the phase differential between described local carrier and incoming carrier within the long noncoherent accumulation time;

Yardage controlled oscillator, for according to the pseudo-code frequency regulating local pseudo-code generator to export through the phase differential between filtered described local pseudo-code and input pseudo-code, upgrades the local pseudo-code signal copied;

Carrier number controlled oscillator, for according to regulates sine to copy through the phase differential between filtered described local carrier and incoming carrier frequency that carrier signal and cosine copy carrier signal.

7. moving window loop tracks device according to claim 6, is characterized in that, described carrier wave ring Discr., specifically for:

Four times adjacent coherent integration values on described first tributary signal and instant branch road corresponding to the second tributary signal are carried out noncoherent accumulation, and the result according to noncoherent accumulation carries out carrier wave ring phase demodulation, obtains the phase differential between local carrier and incoming carrier.

8. moving window loop tracks device according to claim 6, is characterized in that, described carrier wave ring Discr., specifically for:

According to formula $\begin{array}{c}{D}_{PLL}=\frac{180}{\mathrm{\π}}\frac{-1}{\sqrt{{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|I_P\left(n\right)\right|\]}^2+{\[\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\]}^2}}\·\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}\left|Q_P\left(n\right)\right|\\ \·\mathrm{sgn}\left\{\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}|I_P\left(n\right)-Q_P\left(n\right)|-\frac{1}{M}\underset{n=0}{\overset{M-1}{\Σ}}|I_P\left(n\right)+Q_P\left(n\right)|\right\}\end{array}$ Calculate the phase differential between local carrier and incoming carrier, wherein, described I _pn () is the integrated value on instant branch road that the first tributary signal is corresponding, described Q _pn () is the integrated value on instant branch road that the second tributary signal is corresponding, described M is noncoherent accumulation number of times.

9. moving window loop tracks device according to claim 6, it is characterized in that, described processor comprises:

Wave filter and amplifier, for carrying out filtering and amplification to satellite-signal;

Frequency mixer, carries out mixing for the sinusoidal wave local oscillation signal described satellite-signal after filtering and amplification and the local oscillator in receiver produced, will be down-converted to intermediate-freuqncy signal through amplification and filtered satellite-signal;

Analog to digital converter, for carrying out analog to digital conversion to described intermediate-freuqncy signal, obtains the digital intermediate frequency input signal of discrete time;

Carrier wave stripper, is multiplied for described digital intermediate frequency input signal is copied carrier signal mixing with the sine produced local in receiver, obtains the first tributary signal; By described digital intermediate frequency input signal and in receiver the local cosine produced copy carrier signal mixing and be multiplied and obtain the second tributary signal.

10. moving window loop tracks device according to claim 6, is characterized in that, described code stripper, specifically for:

Respectively described first tributary signal is multiplied, to peel off the pseudo-code on described first tributary signal and the second tributary signal with the pseudo-code copied local in receiver with the second tributary signal.