Confront The Passive Location Based On A Priori Information Technology Research

Passive locating system can locate and follow targets by taking bearings of the targets'on board radio-electronic equipments or reflection signals of the targets without any electro-magnetic signal radiation. The traditional active radars are aggravatingly threatened by the anti-radiation missile (abbr. ARM) and other electro-magnetic interferences, because of their working pattern-emitting high efficiency electro-magnetic signals. As an emerging electronic counter-measurement technology, passive locating system attracts many attentions and valuations of the experts in this field by its outstanding confidentiality and mobilization.Recently, the technology of signal processing and radar receiver develops rapidly, so fast that the passive locating systems almost have all functions that the active radars can provide. Their locating precision and ability is enhanced with the technology advancing. Both domestic and foreign passive locating systems are reported and revealed, some of them are even equipped and applied in military actions. It's extremely urgent to study the counter-measurements of the passive locating systems.With efforts of data collecting and target analyzing, signal processing and locating methods of the passive locating systems are concluded and preset. This dissertation brings up 4 methods by improving the counter-measurement methods that were used originally in active radar interferences to interfere the passive locating systems: Noise suppressing, vivid fake targets, distributed false targets and virtual tracks. These methods include all conventional methods - suppressing, deceiving and combination of the two.The main works of this essay is:1. Studies and analyzes the existing passive locating systems to draw up conclusions about passive locating methods and technical characteristics. Summarizes the preset information needed to interfere it.2. Concretely expatiates on the principle and policy of the passive locating methods - Time Difference Of Arrival (abbr. TDOA) which is utilized in many modern passive locating systems. Provides two algorithms of TDOA estimating - correlated function and phase TDOA estimation.3. Expounds the principle and means of the four passive locating counter -measurements which designed on the basis of conventional counter -measurements primely used in active radar interferences. Thoroughly analyzes the merits and demerits of the four methods and verifies their effectiveness through simulating.