AFIS – Geodetic Fixed Point Field of Bremen

Fixed points of location and height are proven in the Official Fixed Point Information System (AFIS). Content: Location: ETRS89 Reference System, GRS80 Ellipsoid, UTM Coordinate System Height: DHHN2016 The spatial reference of the official surveying system in Germany is realised by a uniform, homogeneous fixed point field throughout Germany. This consists of the Geodetic Base Network Points (GGP), Height Fixed Points (HFP), Gravity Fixed Points (SFP) and Reference Station Points (RSP). The realisation and safeguarding of the geodetic spatial reference takes place both by permanently marketed fixed points on the Earth’s surface as well as by the active reference stations of the official satellite positioning service SAPOS®. In addition to the provision and maintenance of the nationwide uniform fixed point field, the spatial reference in Bremen is condensed by additional official fixed points. These are: • Location points 1.- 4. Order • Height points 2.- 3. Order • Gravity points 2.- 4. Order • Recording points官方固定点信息系统（AFIS）已验证位置与高程固定点的相关参数。 内容： 位置参考采用ETRS89参考系、GRS80椭球及UTM坐标系； 高程参考采用DHHN2016高程基准。 德国官方测绘系统的空间参考框架通过覆盖全德境内的统一均质固定点场实现。该固定点场由大地基准网点（Geodetic Base Network Points, GGP）、高程固定点（Height Fixed Points, HFP）、重力固定点（Gravity Fixed Points, SFP）以及参考站点（Reference Station Points, RSP）组成。大地空间参考框架的实现与维护，既依托地球表面永久布设的地面固定点，也依托官方卫星定位服务SAPOS®的主动参考站。除提供并维护全国统一的固定点场外，不来梅地区还通过增设官方固定点加密细化本地空间参考。 此类固定点包括： • 1等、2等、3等、4等位置点 • 2等、3等高程点 • 2等、3等、4等重力点 • 记录点