Loop tracking method and system.

A loop tracking and branching technology, applied in the field of satellite navigation applications, can solve the problem that the GPS receiver cannot track the satellite signal loop and cannot achieve positioning and navigation.

CN105629268AInactive Publication Date: 2016-06-01SPACE STAR TECH CO LTD
4 Cites 14 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2016-06-01
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention provides a loop tracking method and system. The method includes the following steps that: received satellite signals are converted to digital intermediate-frequency signals; the coherent integral values of an instant branch, a lead branch and a lag branch are calculated according to the digital intermediate-frequency signals; the coherent integral values of the instant branch is inputted into a carrier loop phase discriminator, the coherent integral values of the lead branch and the lag branch are inputted into a code loop phase discriminator; a linear state equation is established, and results outputted by the carrier loop phase discriminator and the code loop phase discriminator are adopted as observation vectors, and Kalman filtering is performed on the observation vectors. According to the loop tracking method and system of the invention, the Kalman filtering and the traditional tracking loops are coupled; the output of the code loop phase discriminator and the carrier loop phase discriminator is adopted as an integrated body so as to be subjected to adaptive processing; dynamic adjustment of loop noise bandwidth can be realized, and the loop noise bandwidth can be adjusted in real time adaptively with the change of an environment; the advantages of the Kalman filtering in dynamic data processing can be given to full play; higher-accuracy of positioning and navigation can be achieved in a high-dynamic environment.
Need to check novelty before this filing date? Find Prior Art

Description

Technical field

[0001] The invention belongs to the field of satellite navigation applications, and particularly relates to a satellite signal loop tracking method and system that can be used in a high dynamic environment. Background technique

[0002] With the development of national defense and military, the dynamics of advanced weapons and equipment such as missiles and fighters are getting higher and higher, which makes it impossible for traditional GPS receivers to navigate and locate them. The existing loop tracking scheme must be improved. In a high dynamic environment, the receiver and the satellite have relatively large relative speeds, accelerations and even jerk. For example, the overload capacity of close-range combat bombs can reach 40g, that of medium-range bombs is about 20g, and cruise missiles are about a few g.

[0003] In the above-mentioned high dynamic environment, the GPS signal received by the GPS receiver contains a large Doppler frequency shift and its rate...

Examples

Embodiment 2

[0065] On the basis of the method provided in the first implementation, this embodiment combines specific application scenarios and engineering implementation cases to provide a better technical specific implementation and simulation verification results:

[0066] The selection of the Kalman filter state vector:

[0067] X k =[τ k θ k f k f k '] T

[0068] The 4th-order linear state equation:

[0069] X k+1 = F k+1,k X k +G k f k +W k

[0070] τ θ f f ′ k + 1 = 1 0 Δt λ Δt 2 2 λ 0 1 2 πΔt πΔ t 2 0 0 1 Δt 0 0 0 1 τ θ f f ′ k + - Δt 0 0 - Δt 0 0 0 0 ω code f carr + W k

[0071] In the above equation of state, τ k It is the difference between the real code phase and the local reproduced code phase, the unit is the number of C / A ...

Embodiment 3

[0088] Corresponding to the methods provided in the first and second embodiments, this embodiment also provides a loop tracking system, such as image 3 The shown system composition architecture diagram, the system includes:

[0089] The signal conversion module 301 is used to convert the received satellite signal into a digital intermediate frequency signal;

[0090] The coherent integral value calculation module 302 is configured to calculate the coherent integral value of the instant branch, the leading branch and the lagging branch according to the digital intermediate frequency signal;

[0091] The carrier loop phase detector 303 is used to process the coherent integral value input on the instant branch;

[0092] The code loop phase detector 304 is used to process the coherent integral input from the leading branch and the lagging branch;

[0093] The Kalman filter 305 is used to establish a linear state equation, and perform Kalman filtering with the output results of the carrier ...