The communication system utilizes transmitters that provide communication
transmissions having deterministic data. Receivers of the system have the
digital processing capability for correlating received transmission
reflections of the deterministic data amongst the receivers, the
reflections of the deterministic data being from objects within the
transmission range of a respective transmitter. The correlating includes
utilizing relatively weak multipath signals of the transmission
reflections and the superimposition of external data therewith to provide
a resulting data base of range reflections. The range reflections are
provided to others of said plurality of receivers for processing to
derive the environment and the locations and movements of objects without
the use of a specific interrogation signal, thereby providing situational
awareness.