The selection of underwater gravity field adaptation zones plays a crucial role in gravity-matching navigation systems.Traditional methods for zone selection usually employ the statistical characteristics of the gravity field regions,but there is an issue of inaccurate description of directional adaptability features.Consequently,there is often a significant decrease in matching accuracy for certain trajectory directions within the adaptation zones.In this paper,a novel direction-based adaptation zone selection method is proposed based on Haar wavelet transform.By recombining the high-frequency information maps obtained from the wavelet transform,high-frequency gravity information maps tailored to any specified heading direction can be generated.Experimental validations are conducted on shipborne gravity data in a specific sea area.The proposed method is capable of selecting more targeted adaptation zones according to the current heading direction,resulting in higher matching accuracy with a 6.3％improvement in matching rate within the adaptation zones.The proposed method not only overcomes the limitations of existing zone selection methods in accurately describing directional adaptability,but also provides guidance for the selection of heading directions for underwater vehicles entering the adaptation zones.
gravity field directionality matching areaHaar wavelet transformweight functiongravity-matching navigation
万方数据
维普
