Passive Coherent Location and Passive ESM tracker systems synergy

Indisputable synergy between Passive ESM (Electronic Support Measurement) Tracker (PET) and Passive Coherent Location (PCL) systems, intended for air traffic surveillance, exists in terms of aircraft´s cooperation demands. While PET relies on signals of various kinds emitted by aircraft, the PCL system evaluates scattered signals and therefore, no level of `cooperation´ is required. This paper deals, beside procedure of evaluating the PCL performance, with other synergy effect that can lead to higher positioning accuracy by combining both systems. This effect arises from different mathematical means of estimating aircraft´s position together with different systems´ geometries.