Retrodirective array radar cross-section performance comparisons

This paper reports on the comparison of the radar cross-section (RCS) of a 4-element retrodirective array (RDA) calculated from its measured gain with the predicted RCS of a flat plate, and a 90° dihedral corner reflector. The comparison showed that the boresight RCS of the 4-element RDA is 2.33 dB higher than the boresight RCS of the 90° dihedral passive corner reflector, but 3.66 dB lower than the flat plate at broadside Incidence of the same sizes. In this paper, the different scattering field effects that cause the RCS of the 4-element RDA to be lower that the RCS of the flat plate at angles less than ±10° was explained. In addition, the paper shows for the first time that retrodirective arrays can be made to have better or worse RCS performance than passive reflectors depending on the gain of the antenna elements and the performance of the conjugate circuit