GPS控制网设计

根据需要,拟在宜昌以下河段新建首级GPS控制点40个,同时兼顾可利用的旧点及邻近国家高等级点联入新网。Ⅱ级控制在首级控制网下加密,兼顾常规测量方法需要,利用原有可利用控制点联测转换,计350点,高程控制在长江中下游建三等水准420点。建立独立的局部首级控制系统。一期工程建成后,将建立一套航道测量GPS控制网点,同时检核、提高原有可利用控制点的精度,为航道开发、建设提供高精度的、使用方便的控制资料,适应航道测量工作需要。

GPS Control Network Designs

According to need,we need to construct 40 new GPS control points at the reach of Yichang,at same time,make use of old control points and high-level points neighbouring countries.Grade Ⅱ control is intensified in the first step control point net.Considering the need of a general survey,we use the original control points to conduce survey and convert,which are 350.For elevation control,we construct the third level of 420 control points at the middle and lower reaches of Yangze River.As we examine and check,improve the accuracy of original control points to improve the control data with high precision and convenience for waterway development and construction,and adapting to the requirement of waterway measures.