Journal Paper

Reconfigurable antennas dynamically alter intrinsic radiation parameters such as polarization, operating frequency, and beam steering. Their relevance has rapidly increased in recent years to support multiple satellite constellations and to mitigate interference in high data-density wireless environments, including emerging 5th Generation and 6th Generation networks. In this context, this paper surveys the state-of-the-art in reconfigurable microstrip patch antennas through a novel structure-based classification that organizes designs by where reconfiguration occurs within the antenna (feeding network, radiating element, substrate, ground plane, meta-antenna). Moreover, this document systematically compares antenna designs across three categories: Mono-Reconfigurable (single parameter), Hybrid Reconfigurable (two independent parameters), and Multi-Reconfigurable (three independent parameters), revealing which technique combinations enable multi-parameter designs and which remain unexplored. Additionally, the antennas mentioned in each architecture are analyzed regarding their respective enabling technologies (e.g., Positive-Intrinsic-Negative diodes, varactor diodes), as well as their design approaches with detailed comparison tables providing quantitative performance metrics. Finally, dominant trends and current limitations are identified and discussed, particularly the finding that over 60% of all designs operate below X-band, highlighting critical research gaps for 5th Generation and 6th Generation applications requiring K- and Ka-band operation. The advantages, trade-offs and implementation challenges of the different design techniques are discussed, and research directions with the greatest potential for advancing next-generation reconfigurable adaptive antenna systems, are outlined.