Unilateral Single-Pole Multi-Throw Filtering Switch Using Spatiotemporally Modulated Resonator Arrays

This paper presents a novel unilateral single-pole multi-throw (SPMT) switch with co-integrated RF filtering functionality. It is based on spatiotemporally-modulated coupled resonator arrays whose modulation characteristics can be altered to enable the realization of a unilateral SPMT switch with intrinsically-switched unilateral bandpass filtering (BPF) parts and dynamically-reconfigurable input/output ports. An intrinsic switching-off mechanism is proposed using a combination of moderate-modulated, over-modulated and static resonators. For proof-of-concept demonstration purposes, a three-port single-pole double-throw (SPDT) BPF prototype having three intrinsically switched fifth-order BPF unilateral paths was manufactured and experimentally validated at 1.18 GHz. It demonstrated an insertion loss between 4–4.7 dB and isolation levels exceeding 15 dB across all reconfigurable states.