High-dynamic BOC (binary offset carrier) spread spectrum signal carrier tracking method based on expanded-dimension SRUKF (square root unscented Kalman filter)

Abstract

The invention relates to a high-dynamic BOC (binary offset carrier) spread spectrum signal carrier tracking method based on an expanded-dimension SRUKF (square root unscented Kalman filter), and belongs to the technical field of navigation. According to the method, firstly, captured BOC signals are subjected to phase rotation and integration zero clearing, two paths of signals of an in-phase branch and an orthogonal branch are obtained, next, the two paths of signals are subjected to cross product and dot product frequency discrimination operation, then, an expanded-dimension SRUKF model is built according to obtained operation results, in addition, the expanded-dimension SRUKF model is used for estimating the signal carrier frequency and the derivative of the signal carrier frequency, and a local NCO (numberically controlled oscillator) is regulated according to the estimated result. Observation noise and process noise variances need to be separately estimated in the existing carrier tracking method, and according to the high-dynamic BOC spread spectrum signal carrier tracking method, the observation noise and process noise variances can be estimated through dimension expansion, so the complexity of a tracking loop is greatly reduced, the tracking speed of a loop is further accelerated, and the accuracy of the loop is further improved.

Description

technical field [0001] The invention belongs to the technical field of navigation signal tracking, and relates to a high dynamic BOC spread spectrum signal carrier tracking method based on extended dimension SRUKF. Background technique [0002] Binary Offset Carrier (BOC) modulation is a new type of spread spectrum signal modulation in the field of satellite navigation. It has been adopted by L1C of GPS, E2+L1A+E1 of Galileo, and my country's Beidou navigation and positioning system. Navigation and positioning receivers generally work in a high dynamic environment, and there will inevitably be a large relative velocity and acceleration, or even jerk, between the carrier and the receiver, causing the received signal to cause a large Doppler frequency on the carrier frequency. Frequency shift and its higher order derivatives. This greatly reduces the carrier tracking accuracy of the navigation and positioning receiver for the BOC modulated signal, and even causes the tracking...

AI Technical Summary

Problems solved by technology

Tian Tian et al. proposed a carrier tracking loop based on extended Kalman filtering, but this method has the disadvantages of large linearization error and difficulty in calculating the Jacobian matrix.

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