P.D. Tumanov - Head of Laboratory, JSC «RPC «NIIDAR». E-mail: tprohor@mail.ru О.А. Agapov - Engineer, JSC «RPC «NIIDAR». E-mail: stealth333@yandex.ru А.P. Bondarenko - Ph.D. (Eng.), Senior Research Scientist, Chief Research Scientist, JSC «RPC «NIIDAR». E-mail: bond_a_p@mail.ru К.S. Sokolov - Head of RTC, JSC «RPC «NIIDAR». E-mail: sokolovks@inbox.ru

As usual the radar scans the space at the same elevation angle in a wide range of the azimuth angle (barrier scanning area) in coor-dinate system, in which elevation angle means the angle between the horizontal plane and the direction to the target, the azimuth angle means the angle between the bisector of the radar-s sector and the projection of the vector to the target in the horizontal plane. The process of target searching inside the barrier scanning area using a narrow beam is too time-consuming. Beam broadening is useful for reducing phased-array radar-s time of scanning for targets detection. The azimuth angle beam broadening for a vertical antenna is given by special horizontally phase distribution in antenna array plane. The elevation angle beam broadening for a vertical antenna is given by special vertically phase distribution in antenna array plane. In case of inclined antenna, the widened radiation pattern «rotates» in the azimuth-elevation angle plane when the scanning beam deviates from the normal to the antenna in azimuth angle. Therefore, beam broadening in any coordinate is given by special phase distribution for the both orthogonal components. The widened radiation patterns «rotation» reduces the overlap area of neighboring radiation patterns and results to the appearance of "energy holes" inside the barrier scanning area. The probability of detection of targets moving through "energy holes" inside the barrier scanning area can become unacceptably low. This problem can be solved by rotating of each radiation pattern in the azimuth-elevation angle plane to required position. This may increase the overlap areas of neighboring radiation patterns, and increase the energy level inside the overlap areas. The required widened radiation pattern-s position can be calculated by following method: 1) simulation of antenna array rotation to the required angle (receiving virtual antenna array-s coordinate system); 2) calculation of coordinates of initial antenna array-s elements in virtual antenna array-s coordinate system; 3) calculation of the phase values for initial antenna array-s elements using phase-only synthesis method for a linear antenna array; 4) calculation of the phase values for initial antenna array-s elements using bilinear interpolation equations and phase values for virtual antenna array-s elements. The presented method allows reducing the unevenness of the energy distribution inside the barrier scanning area caused by radiation pattern rotating for inclined antenna. The presented results require further confirmation by experiments.

 

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