对中国高程控制网现代化工作的思考
On the Modernization of Chinese National Height Control Network
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摘要: 随着空间和信息技术的快速发展,我国测绘基准中的国家高程控制网现代化也迫在眉睫。它应包括两个部分,一是国家高精度水准网,即mm级一等水准网的更新;二是具有cm级精度的(似)大地水准面的确定。建议切实执行《中华人民共和国测绘法》中“基础测绘成果应当定期更新,国民经济、国防建设和社会发展急需的基础测绘成果应当及时更新”的规定,尽快组织施测国家三期一等水准网,以保证国家高程控制网mm级高精度的可靠性和现势性。另一方面,应结合GPS水准和重力测量精化我国大陆的(似)大地水准面至cm量级,以利用GPS+(似)大地水准面的技术求解相当于二、三等水准测量精度的正常高,这不仅可以改变传统高程测量的作业模式,节约人财物和时间,而且获得的点位高程的精度比较一致。在海岛、山区等困难或无法传递水准测量高程的地区,采用这一技术可以快捷地测得高程,其成果与国家高程基准、高程系统是统一的和协调的。Abstract: Considering the rapid development of space and information technology,Chinese national height control network,as one of the backbones of geographical spatial fundamental infrastructures,is necessary to be updated and modernized.There are two tasks for the modernization of Chinese national height control network,the first one is to update the national 1st order leveling network.To lay down a national 3rd term 1st order leveling network in the near future is according to the "Law of Surveying & Mapping of the Peoples Republic of China",which defines that "national base surveying & mapping results should be updated in certain term and base surveying & mapping results urgently needed by national economy,defense construction and social development should be updated in time." It is the guarantee to keep the Chinese vertical datum and normal height system updated and reliable.The second task is to refine the Chinese quasi-geoid to cm magnitude accuracy and 5′×5′resolution.The "GPS + geoid" technique can be used to obtain altitude with cm accuracy at any place in Chinese mainland easily and quickly.Then the modern Chinese national height control network will be a reliable and suitable height frame in the geographical spatial fundamental reference frame for China before the year of 2020.