An Out-of-Band Low RCS Microstrip Patch Antenna Using a Back-Loaded Triplexer

An out-of-band low RCS microstrip patch antenna using a back-loaded triplexer is proposed in this paper. By designing the working frequency band of the triplexer within that of the antenna, the frequency band of the antenna can be divided into three bands. Taking band 2 of the triplexer as the actual working band of the low RCS antenna, and designing the matching load for bands 1 and 3, the incident waves in the out-of-band of the low RCS antenna can be absorbed, and the out-of-band low RCS performance can be realized. The simulated result shows that the RCS of the proposed antenna is reduced by 20 dB at 7.25 GHz and 23 dB at 8.7 GHz, respectively.