ABSTRACT This paper presents an integrated architecture based on spoof surface plasmon polariton (SSPP) metamaterials for radio‐frequency power amplifier (PA) design, which achieves remarkable performance in bandwidth expansion and miniaturization. We propose an atypical meander‐line SSPP unit that, compared to the conventional comb‐like structure, provides a lower cutoff frequency and stronger field confinement under identical physical dimensions, thereby laying the foundation for device miniaturization. Aiming at the difficulty of impedance extraction of atypical SSPPs, a characteristic impedance extraction network based on inversion method is introduced, which can accurately extract the impedance characteristics of any SSPPs structure and solve the impedance calculation problem of atypical SSPPs. Simulation and experimental results demonstrate that the implemented PA with the proposed atypical SSPP structure achieves an output power of 40.2–42.9 dBm and a power‐added efficiency (PAE) of 61%–71.5% over the 0.8–3.2 GHz frequency band, while maintaining an ultra‐compact form factor of 47.7 mm × 10.3 mm. This design exhibits significant improvements in both output power and power‐added efficiency, concurrently accomplishing a substantial reduction in physical size.
Wáng et al. (2026) studied this question.