Communication network with mobile nodes; the project state 2008


  • Tommy Öberg
  • Erland Sangfelt
  • Jan Nilsson

Publish date: 2008-12-18

Report number: FOI-R--2669--SE

Pages: 21

Written in: Swedish


  • underwater communication
  • sonar signal processing
  • network


In this user report, the activities during 2008 in the project: "communication networks with mobile nodes" and a small survey of the state in the uw-communications are given. Both civilian and military needs are pushing the development forward. The military applications are communication to a submarine, communication to and from an AUV, and sensor networks under water. For example, the number of ship based units for anti submarine warfare is decreasing and a change towards the use of AUV:s and wireless sensors is going on. In the report, the three uw-communications experiments, that has been done during the year, at Gotland, Horsfjärden and Bergen, are discussed. The last one was done within in the UCAC framework. Some results to mention are the transmission of 10 kb/s over 40 km and stealth communication over 50 km. The long-term experiment shows that an underwater link over 3 km is rather reliable. The work with the development of the communication link has mostly been directed to channel estimation and equalizer, which is reported in short. New channel estimation and phase tracking have considerably improved the receiver. A new and better modulation scheme for stealth communication is presented. A simulation study of the network´s efficiency in different variants has been done and a summary of the study is given. A discussion about the future in the uw-com. is given in the report.