A multifunctional active frequency selective surface with parallel feed network

In this paper, we propose a multifunctional active frequency selective surface (MAFSS), which can be switched freely between the electromagnetic switching function and the polarization selection function. Thus, four different working states can be attained by controlling two external bias networks independently. Resonant structures take upon themselves the role of allowing DC currents to pass through and no extra feed lines are needed within the MAFSS array, which greatly reduces the feed network's negative impact on transmission properties. In addition, the proposed structure demonstrates great stability with respect to different incident angles and polarizations.