Reconfigurable 4 × 4 multi-port amplifier with switchable input and output matrices

This study presents a new reconfigurable 4 × 4 multi-port amplifier (MPA) configured by switchable matrices. The proposed structure adopts two 4 × 4 switchable matrices consisting of four unit-switching mode hybrid matrix (SMHM) where each SMHM is implemented with two 3 dB couplers and two single pole four throw (SP4T) switches. Comparing with previously reported MPA structures with fixed input and output relations which are exposed to performance degradation by power amplifier (PA) failure, the proposed structure can flexibly adjust signal paths. Also, the number of PAs used for signal amplification can be adjusted by controlling proper modes of SP4Ts in switchable matrices. For 4 × 4 structure, input signal can be amplified by a single PA, two PAs or all four PAs and then be outputted to only one port, two ports or all four ports. Thus, the proposed MPA structure can effectively improve system flexibility as well as reliability in case of PA failure. For the ease of verification, the proposed structure is tested at ISM band of 902–928 MHz.