V. I. Merkulov - Dr.Sci (Eng.), Professor, Deputy of General Constructor, JSC «Radio Engineering Corporation «Vega» I. V. Zabelin - Ph.D. (Eng.), Head of Department, LLC «Gazprom Inform»

One of the peculiarities of state coordinates estimation in dual-position airborne radar is the time difference between measurements from the same target for different positions, which leads to asynchrony of arrival of measurements into combined filtration algorithm. This peculiarity makes it impossible to use classic algorithms of estimation. Elimination of this demerit was achieved by using algorithm of analogue-discrete filtration that extrapolates state coordinates with minor increments (making it almost equal with analogue filtration in accuracy), while the measurements are sparse. This approach allows forming the estimations regardless of the actual time of measurements arrival. Synthesis of the algorithm of estimation of state coordinates was carried out for a dual-position passive system consisting of a tactical aircraft, which illuminates the target (information position) and an air-to-air missile in passive mode (strike position). The synthesis and following analysis of the algorithm were done under the assumption that there are direct measurements of target range and bearing in relation to the information position, as well as indirect measurements of the target coordinates in Cartesian coordinates and target range and bearing in relation to the strike position.