Air surveillance by passive multisensor systems

It is very important to provide continuous air surveillance in to realize modern operations on the operational-strategic level and tactical, as well. It is well known that active radar systems, on which air surveillance is based in our country, are very vulnerable in war times and susceptible to the electronic counter and combat attacks of the enemy, what is shown practically in 1999 war. Air surveillance by passive multi-sensor systems is a possible alternative to the air surveillance by the active radar systems. Subjects of our wider research are technical solutions of integrated multi-sensor systems for passive air surveillance which consists of the following subsystems: a subsystem for the air communication intelligence within the frequency range 20-3000 MHz based on intercept/direction finding principle, a subsystem for the air surveillance based on the acoustic intelligence, a subsystem for the air surveillance based on the station for the visual intelligence, a subsystem for air surveillance based on thermo-vision and television principle. General principles of air surveillance are presented, and the concepts of the subsystems for the air communication intelligence and acoustic intelligence are proposed in this paper.