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 paths with unilateral transmission 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.