【正文】 Mapping Technology INC, Dalian Urban Surveying Design Institute, Siwei Aviation Remote Sensing Co. Ltd., Xi’an National surveying amp。181。 stereo model reconstitution。 ground control points (GCPs)。181。 Mapping Aviation Remote Sensing Co. Ltd and so on. These supports are gratefully acknowledged. The author would like to express his hearty gratitude to Fu Jianhong, Xie Chou, Ji Shunping and Yang Ming for participating in partial experiments. The author would like to thank Yang Ming and professor Zhang Jingxiong for their polishing in English. References [1] Li Deren, Shan Jie (1989) Quality analysis of bundle block adjustment with navigation data [J]. Photogrammetric Engineering and Remote Sensing, 55(12):1 743 1 746 [2] Ackermann F (1994) Practical experience with GPS supported aerial triangulation [J]. Photogrammetric Record, 16(84):861874 [3] Yuan Xiuxiao (2020) The principle and application of GPSsupported aerial triangulation [M]. Beijing: Publishing House of Surveying and Mapping (in Chinese) [4] Cannon M E, Sun H (1996) Experimental assessment of a nondedicate GPS receiver system for airborne attitude determination [J]. ISPRS Journal of Photogrammetry amp。 POS photogrammetry can be used for the production Geospatial Information Science 11(4): 235242 242 of orthophotos and update of 4D products in small regions. However, POS has a promising prospect in the field of largescale urban mapping, LIDAR, and digital aerial photogrammetry. We should promote the integration technology of POS system and other sensors by undertaking large scale experiments, thus providing technical support for economical and rapid gathering of geospatial information. Acknowledgement The experiment data acquisition are supported by Institute of Remote Sensing Applications Chinese Academy of Sciences, Zhong Fei General Aviation Company, Liaoning Jingwei Surveying amp。22, X YXY181。 POS (position and orientation system)。 accuracy CLC number Introduction Aerial photogrammetry is the science and technology for obtaining 3dimensional spatial information about the Earth’s surface from aerial images. Photogrammetric point determination, which locates ground objects by using images, is the basis for object recognition in remote sensing. And the key point of this issue is the rapid and accurate determination of an image’s position and behavior at the instant of imaging. This goal was met by aerial triangulation based on well distributed GCPs. With the development of spatial positioning technology, remote sensing technology, and puter science, aerial triangulation evolved and progressed towards digital mapping without GCPs. In the early 1950’s, photogrammetric scientists began studying how to utilize various auxiliary data to reduce the number of GCPs required. However, the methods haven’t bee practical due to technological limitations[1]. Until 1970’s, with the emergence of American Global Positioning System (GPS), people got to adopt carrier phase differential GPS (DGPS) technology to determine an exposure station’s positions (that is three linear elements of aerial photos) during aerial photographic process, which was used to perform aerial triangulation (called GPSsupported AT for short) that can decrease photogrammetric reliance on GCPs, shorten the mapping cycle, and reduce Received on July 14, 2020. Supported by the National Natural Science Foundation of China (No. 40771176, 40721001), the Program for New Century Excellent Talents in University (No. NCET040662). YUAN Xiuxiao, School of Remote Sensing and Information Engineering, Wuhan University, 129 Luoyu Road,Wuhan 430079, China。=+. 4) Theoretical accuracy of EO is obtained from the unknown covariance matrix calculated according to the law of error propagation,0(,)iiissmQXYZσ ? ωκ== . 1) For test 1, densified points’ horizontal accuracy and vertical accuracy are better than meter, totally meeting the accuracy requirement: meter in planimetry and meter in height[11] of 1:500 Topographic Maps Specifications for Aerophotogrammetric Office Operation for flat land. 2) For test 2, densified points’ horizontal accuracy is better than meter and vertical accuracy better than meter, totally meeting the accuracy requirement: meter in planimetry and meter in height[11] of 1:500 Topographic Maps Specifications for Aerophotogrammetric Office Operation for mountain land. 3) For test 3, densified points’ horizontal accuracy is better than meters and vertical accuracy better than meter, totally meeting the accuracy requirement: meters in planimetry and meters in height[12] of 1:5 000 Topographic Maps Specifications for Aerophotogrammetric Office Operation for mountain land. 4) For test 4, densified points’ horizontal accuracy is better than meters and vertical accuracy better than meters, totally meeting the accuracy requirement: meters in planimetry and meters in height[13] of 1:50000 Topographic Maps Specifications for Aerophotogrammetric Office Operation for high mountain land. It can be seen from Table 2 that for the images of different land types at different scales, the densi