SEA Gate has been deactivated and decommissioned on 30th October 2017.

The SEA Gate system was a stand-alone navigation system, which was equipped by a set of ground based signal transmitters. So called Pseudolites (PSL) were emulating and emitting Galileo like signals within the L-Band. The system was operated within the vicinity of the Rostock port and covered an area of around 20 square kilometers. Based on a specific PSL capable receiver users could have taken advantage to use these signals for absolute positioning. The signals were in conformity with the “Open Service Signal in Space Interface Control Document Draft 1” of the European Global Navigation Satellite System Galileo.