Luftburna noder i marknät - Slutrapport

The project Airborne nodes in communication networks evaluates performance of communication networks with both ground based and airborne nodes. The project is a three-year project that started on January 1, 2012 and ends December 31, 2014. This report summarizes the results generated by the project. Three different scenarios have been analyzed, radio link systems, tactical ground networks and communication with a helicopter. In radio link networks, it can be difficult to replace parts of the network with an airborne node and get the same range, as the airborne node probably uses a simple antenna. Often an antenna with a gain is necessary to obtain the same range. The benefit of an airborne node in a radio link network is likely that they enable a system with less pre-planning and more mobility, but has about the same range as a radio link system. In tactical ground networks, data rate could be increased using an airborne node. Results show that the data rate can be significantly improved for broadcast traffic in a ground network with an airborne node. Moreover, in networks with traffic between pairs of nodes, unicast traffic, an airborne node has proved to be very useful. In a mobile network, links change constantly and therefore it is difficult to send unicast traffic effectively. Hence, using an airborne node can simplify the problem considerably. In order to avoid friendly fire, it is desirable that helicopters can exchange data with ground networks before the helicopter comes within range of fire. The analysis shows that it is possible when the helicopter has a high altitude, 1000 meters, but not at low altitudes, 5-20 meters. In addition, results show that helicopters flying over a mobile network can send and receive traffic at about the same extent as the ground nodes during the few minutes that the helicopters are over the network. Being able to communicate with ground networks during the overflight is a desired ability missing in existing systems.