Non-equally spaced federated filtering method for multi-source information based on filter variance matrix modification

Abstract

The invention discloses a multi-source information unequal interval federated filtering method based on filter variance matrix correction. The method comprises the particular steps that a fused federated filter without a reset mode of an aviation onboard inertial navigation system (INS) and other navigation systems is established, and then the filtering accuracy of a sub-filter is improved by the multi-source information unequal interval federated filtering method based on sub-filter variance matrix correction. An INS / CNS (Communications, Navigation and Surveillance) / SAR (Synthetic Aperture Radar) / TER integrated unequal interval federated filtering realization scheme suitable for a high-altitude long-endurance unmanned aerial vehicle is designed by taking the high-altitude long-endurance unmanned aerial vehicle as an application object and combining the actual sensor use characteristic. The method can improve the fusion accuracy of the filter by correcting a sub-filter filtering variance matrix under the condition that additional calculation burden is increased hardly; the adaptability of the reset-free federated filter applied to multi-source information unequal interval federated filtering is achieved while the characteristics of no reset structure and high fault tolerance are kept; the navigation accuracy of a system is improved further; and the robustness of the integrated navigation system is improved.

Description

technical field [0001] The invention discloses a multi-source information non-equally spaced federated filtering method based on filter variance matrix correction, and relates to the technical field of aircraft integrated navigation. Background technique [0002] UAV technology has become a research hotspot in the aviation field of various countries due to its unique advantages of not being limited by human physiological conditions, simple air crew support and zero casualty rate. With the development of high-altitude and long-haul UAV technology, higher requirements have been placed on the accuracy and reliability of navigation and positioning, and a single navigation system has been difficult to meet the requirements. Taking the typical high-altitude and long-haul UAVs of the United States and other military powers as an example, it mainly uses the combination of inertial navigation system and satellite navigation system, and additionally adds other navigation system electr...

AI Technical Summary

Problems solved by technology

[0004] Due to the introduction of multiple navigation devices in the multi-source integrated navigation, the problem of non-equal interval processing of the filter measurement information caused by the inconsistency of the data update frequency of each navigation sub-filter system will be introduced.

Scholars at home and abroad have proposed improvement measures including proving that its non-equal interval algorithm is equivalent to the centralized Kalman algorithm with a reset structure; the sub-filters sample at the same time and observe the target at the same sampling rate; extrapolation and interpolation There are various methods such as pushing the time of the sub-filter to the fusion time of the main filter, but too many restrictions limit the practical application

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