The United States Navy Electronic Chart Display and Information (ECDIS) development project

The United States Navy has an Electronic Chart Display & Information System (ECDIS) currently in full scale development. This system is called the navigation sensor system interface, or NAVSSI (AN/SSN-6). The NAVSSI will utilize the digital nautical chart (DNC) database for navigation. The DNC database is a global marine charting database being developed by the United States Defense Mapping Agency (DMA). Use of DNCs with NAVSSI will replace the use of paper charts for safe ownship navigation. The goal is for Navy ships to be relying on NAVSSI with DNCs and not paper navigation charts by the year 2000. The paper presents a background on the NAVSSI project and a description of the system hardware and software. NAVSSI compliance with ECDIS performance standards is discussed as well as some unique Navy missions satisfied by the NAVSSI. The NAVSSI accepts inputs from the Global Positioning System (GPS), OMEGA, TRANSIT (SATNAV) and inertial navigation systems (ex. AN/WSN-5) and these inputs are filtered to provide the best available position, attitude and time data. This data is distributed to combat and weapon systems via networks or point-to-point interfaces. The design of the Digital Nautical Chart (DNC) database and the software that has been developed to display and operate the DNC is covered in depth. The database design required new digital standards which were developed by the Navy and DMA