Circle slip detection and repairing method by combining doppler integral method and ionized layer residual error method

Abstract

The invention discloses a circle slip detection and repairing method by combining a doppler integral method and an ionized layer residual error method. The method comprises the following steps of a, acquiring carrier phase and doppler observation values of two frequency points in a navigation system by a receiver separately; b, calculating the detection amount by utilizing a doppler integral method to carry out preliminary cycle slip detection, and judging whether the cycle slip occurs or not; c, if the cycle slip occurs, enabling the original cycle slip detection amount to be corrected to bewithin + / -4 weeks; d, detecting the cycle slip by using the ionized layer residual error method, obtaining a cycle slip detection amount by using a linear combination of carrier phases, and comparingthe detection amount with a threshold value; if the absolute value of the detection amount of the ionized layer residual error method is larger than the threshold value, judging that the cycle slip occurs, and if not, performing step e; if the absolute value of the detection amount is smaller than the threshold value, judging that no cycle slip occurs; and e, repairing the cycle slip value. The method disclosed by the invention can effectively integrate the advantage of strong cycle slip detection capability of the ionized layer residual error method, and also can avoid the defect that the cycle slip combination of a special ratio cannot be detected.

Description

technical field [0001] The invention relates to the technical field of satellite navigation and positioning, in particular to a Doppler integration method combined with an ionospheric residual method to detect and repair cycle slips. Background technique [0002] With the development of precision positioning level, the precision required for positioning products is getting higher and higher. In the process of continuous carrier phase measurement by the receiver, the loss of lock will lead to an error in the whole cycle count, and the phase observation value will be compared with the previous one, and a jump will occur, which is called cycle slip. The observed value for precise positioning is the carrier phase, so to obtain the carrier phase value accurately, cycle slip detection and repair is a key step. The trajectory of the satellite in space is a smooth curve, so the change of the distance observation value from the satellite to the receiver is also smooth and regular. ...

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Problems solved by technology

[0003] (1) For the processing of dual-frequency cycle slips, the MW (Melborne-Wnbbena, MW) combination method of dual-frequency phase and pseudorange is often used. This combination eliminates the influence caused by the station-to-satellite geometric distance and the troposphere, and is suitable for dynamic situations Therefore, at a high sampling rate, it can effectively detect a cycle slip as small as one cycle. However, although the MW combination method can detect a cycle slip, it cannot tell which carrier the cycle slip occurs on, and When the carrier phases of the two frequency band signals have cycle slips of the same size, it will not be able to detect such a cycle slip combination, that is, the MW method cannot detect the same size cycle slips at two frequency points

[0004] (2) Geometric distance combination (GF) cannot detect when the cycle slip ratio on two frequency points is close to the reciprocal of the frequency ratio

[0005] (3) (TurboEdit) method is a method of combining MW combination and GF combination to make up for the shortcomings of their respective methods, but when the pseudo-range noise is large, the cycle slip of one cycle cannot be detected

However, the current Doppler integration detection cycle slip, because of the limitation of Doppler observation accuracy and data sampling rate, its detection accuracy is not high

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