L. S. Vilenchik, P. A. Melyanovsky, V.N. Minaev

A general approach to creation of passive coherent multistatic shortwave radar is presented. The operating principle of passive shortwave radiolocation is described. The principle is based on directional coherent reception of the signals from shortwave radio broadcasting stations reflected by moving radar targets, with their subsequent spectral analysis and moving target detection by the Doppler frequency shift. The potentials of a passive coherent above-the-horizon radar have been analyzed according to detection ranges of aircrafts with different RCS. Power estimation of ionospheric signals of powerful broadcasting stations as emitted signals is given. It-s pointed out that the level of radio emission depends on the state of the ionosphere, propagation conditions, station distance, transmitter power and transmitting antenna gain. Calculated aircraft detection ranges are presented for non-fluctuating and fluctuating emitted ionospheric signal of a passive coherent above-the-horizon shortwave radar. The possibility of using of a monostatic passive coherent radars for building passive multistatic shortwave radar systems is mentioned.