利用高程基准模型实时获取海拔高技术研究

摘要

Elevation information is an important part of time and space position.Real-time acquisition of high-precision elevation is one of the key steps in mapping navigation information.The navigation terminal of Beidou Navigation Satellite System can quickly and efficiently determine the geodetic high,and also can obtain real-time precise elevation combing with high-precision digital elevation model.Based on the vertical deviation between the National Height Datum 1985 and the Global Height Datum,this paper constructs a regional digital elevation datum model unified into the CGCS 2000 ellipsoid using GOCE + EGM08 gravity field model.The model range corresponds to the BDS service area,namely 55 degrees south latitude to 55 degrees north latitude and 55 degrees east longitude to 180 degrees east longitude.The model accuracy is better than meter level,which meets the requirement of using BDS navigation terminal on application of high altitude requirements.Based on real-time SQLITE database technology,and digital height datum model,a real-time elevation access system using BDS navigation terminal is built to achieve real-time precise elevation at any point.%高程信息是时空位置的重要组成部分,实时获取高精度海拔高是测绘导航信息化的关键步骤之一.北斗导航终端能快速高效地测定大地高,结合高精度的数字高程基准模型,可实时获取精密海拔高程.在顾及1985国家高程基准与全球高程基准之间垂直偏差的基础上,基于GOCE+EGM08重力场模型构建了统一到CGCS 2000椭球的区域数字高程基准模型,该模型范围对应北斗区域导航的覆盖范围,即55°S～55°N,55°E～ 180°E,模型精度优于米级,满足北斗导航终端对海拔高的应用需求;利用实时SQLITE数据库技术,基于该数字高程基准模型构建了北斗导航终端的海拔实时获取系统,实现了任意测点精密海拔高程的实时获取.