ERRORS IN DIRECTION-FINDING OF RADIANT UNDER THE ACTION OF RADIO WAVES DIFFRACTION ON THE OBSTACLE BOUNDARY

Abstract
Computer simulation of a low-altitude target elevation angle measurement over a rough sea surface under conditions of a strong diffuse reflection is performed using MUSIC method. It is found that a part of diffuse reflection arriving from the “glittering” surface, the zone nearest to the radar, exerts the greatest action on the errors. The axes, being a part of the receiving antenna array, are offered to align at the positive angle to the interface with the aim to reduce the errors value. In this case the antenna radiation patterns should suppress as much as possible the diffuse reflection signals arriving from the near zone ensuring a sufficient level for reception of the signal arriving from the target. Characteristics of elevation angle measurement errors in various phases of interference of primary and mirror signals in the receiving antenna array center and at different angles of elevation of receiving antennas axes are analyzed.
KEY WORDS:diffraction, azimuthal errors, small angles of sliding

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