Comparison of Van Atta Arrays with Two Different Feed Structures

In this paper, a comparison of Van Atta arrays based on direct feed network and couple feed network is presented. The proposed arrays are based on a general microstrip structure comprising a direct feed microstrip antenna and a couple feed microstrip antenna. The Radar Cross Section (RCS) of the Van Atta array based on a direct feed microstrip antenna shows pronounced fluctuations and cancellations in other directions of the principal direction due to the feed network and antenna scattering. Still, it emerges maximum in the radiation direction because it has a higher gain than the Van Atta array based on a couple feed microstrip antenna. In addition, the operation bandwidth of the coplanar design of the Van Atta array is especially narrow due to the feeding method selected. On the contrary, the Van Atta arrays based on a couple feed microstrip antenna have a wider bandwidth and lower scattering caused by the structure mode, including feed network and antenna, which makes it have a wider and flatter RCS beamwidth over the 1GHz operation band. The back approach minimizes scattering due to structure modes and thus increases RCS beamwidth, which provides valuable guidance and experience for designing passive retrodirective arrays in the future.