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A 3D passive surveillance system VERA accuracy analysis

The passive surveillance system VERA consists basically of three or more terrestrial stations receiving simultaneously the signal of an airborne secondary surveillance radar transponder. The emitter position is evaluated using the corresponding time of arrival (TOA) measurements. The system is produced in several versions, designed for various applications. The four position three-dimensional model of the VERA system is briefly described and the accuracy of aircraft position measurement is analysed and compared with experimental results. The effect of simultaneous direction of arrival (DOA) measurement is also evaluated and discussed.