Combined navigation method based on INS (inertial navigation system)/GPS (global position system)/SAR (synthetic aperture radar)

Abstract

A combined navigation method based on an INS (inertial navigation system) / GPS (global position system) / SAR (synthetic aperture radar) comprises steps as follows: an INS receiver, a GPS receiver and an SAR sensor are mounted in appropriate positions of an unmanned aerial vehicle in parallel; image matching is performed, and position navigation deviation of the INS is obtained and taken as an observed quantity to be input into a filter, and the observed quantity and other observed quantities are jointly filtered; GPS measuring deviation is obtained and taken as an observed quantity to be input into the filter, and the observed quantity and other observed quantities are jointly filtered; the filter integrates the measuring deviation from the GPS and the position navigation deviation, obtained through image matching, from the INS, and a navigation error estimated value is calculated. Topographic features are automatically and reliably extracted from an SAR image, a map image is formed in a digital map, and the SAR topographic features are automatically predicted; topographic deviation is accurately estimated and integrated; capture and matching are automatically initialized; the fault tolerance capability, the autonomy and the reliability of navigation are high.

Description

technical field [0001] The invention belongs to the technical field of target recognition and navigation information, and in particular relates to a joint navigation method based on INS / GPS / SAR. Background technique [0002] At present, UAV-borne SAR (Synthetic Aperture Radar) data acquisition systems mostly use INS (Inertial Navigation) / GPS (Global Positioning System) navigation methods. When INS / GPS navigation is used, the redundant information provided by INS and GPS navigation systems is limited, resulting in a weak system fault tolerance. Moreover, because the GPS signal is easily interfered and my country does not have the ownership of GPS, the navigation system is unstable and the autonomy is weak. [0003] For the UAV-borne SAR data acquisition system, due to the small body of the UAV, the low flying height, and the great influence of the air flow, its motion stability is difficult to achieve the motion state required by SAR imaging. Therefore, during the data acqu...

AI Technical Summary

Problems solved by technology

When INS / GPS navigation is used, the redundant information provided by the INS and GPS navigation systems is limited, resulting in a weak system fault tolerance

Moreover, because the GPS signal is easily interfered and my country does not have the ownership of GPS, the navigation system is unstable and the autonomy is weak

[0003] For the UAV-borne SAR data acquisition system, due to the small body of the UAV, the low flying height, and the great influence of the air flow, its motion stability is difficult to achieve the motion state required by SAR imaging.

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