QZSS亚米级增强服务和MSAS增强定位性能评估

日本QZSS亚米级增强服务(SLAS)和多功能卫星增强系统(MSAS)均用于增强单点定位性能，但其服务范围和服务原理不尽相同。为了对这两种增强服务进行增强性能评估，以伪距单点定位结果为基础，比较在日本境内和中国及周边地区使用这两种增强服务增强后的定位结果，分析和评估不同地区两种增强服务的增强性能和适用性。结果表明：在日本境内，SLAS和MSAS均能显著实现定位增强效果，SLAS在水平和高程方向定位精度分别为0.55m和0.9m，提升约51.8%和73.8%；相应地，MSAS定位精度分别为0.69m和0.97m，提升约39.8%和71.8%；表明前者增强效果更好。在中国及周边地区，MSAS增强定位效果更好，但要求离中心服务区越近越好；SLAS也能增强定位效果，但提升效果较小，且当测站离中心服务区超过一定距离时，会出现定位精度负提升的情况。

Augmented Positioning Performance Evaluation of QZSS Sub-meter Level Augmentation Service and MSAS

Japan''s QZSS sub-meter level augmentation service(SLAS) and multi-functional satellite augmentation system(MSAS) are both used to enhance the performance of single point positioning, but their service area and principles are different. In order to evaluate the augmentation performance of SLAS and MSAS, based on the pseudorange single point positioning results, this paper compares the positioning results of the two augmentation services in Japan, China and the surrounding areas, and then analyzes and evaluates the augmentation performance and applicability of the two augmentation services in different areas. The results shows that both SLAS and MSAS can significantly achieve the positioning augmentation effect in Japan. The positioning accuracy of SLAS in the horizontal and vertical directions is 0.55m and 0.9m, with an increase of about 51.8% and 73.8%, respectively; correspondingly, the positioning accuracy of MSAS is 0.69m and 0.97m, which is improved by about 39.8% and 71.8%. The former has better augmentation effect. While in China and its surrounding areas, MSAS is more effective for augmented positioning. However, it is required to be as close as possible to the central service area. SLAS can also augment the positioning effect, but only with a little the improvement, and when the station exceeds a certain distance from the central service area, there will be a negative increase in positioning accuracy.