This report describes the introduction of Blue Force Tracking (BFT) into the EWSim simulation facility. BFT is a type of system that is designed to track the positions of friendly forces. Platform positions are normally acquired by GPS. Data as position, velocity etc. are distributed to a staff to be merged to a situation of awareness. BFT has been introduced for two main reasons, first to study effects of jamming the positioning system and the distribution net and second to study how a BFT-systems reveals itself to non-friendly signal-reconnaissance units. The GPS-part of BFT handles both military and civilian GPS. There are two possible ways to jam the GPS-receiver, either by ordinary white noise or by spoofing. The military GPS is more diffcult to jam and spoof than the civilan GPS. If the GPS is jammed it is possible to use an inertial navigation system as back-up. BFT-data is distributed to all units having BFT-facility within a defined net. Which units that belong to a certain net is defined in a scenario before the actual simulation begins.