Active-Passive Reconfigurable Antenna Covering 70-7200 MHz Bandwidth

This communication presents an active-passive reconfigurable antenna with 70-7200 MHz bandwidth for multiple wireless services. The active-passive reconfiguration is achieved by reusing a properly designed monopole antenna with active-passive reconfigurable matching circuit, which is composed of a passive path and an active path. The passive path guarantees an inherent bandwidth of 923-7200 MHz for higher frequencies. While the active path, achieved by a transistor biased in its ohmic region, ensures the impedance matching within 70-1200 MHz for lower frequencies. The path selection is facilitated by the cooperated design among the transistor, the PIN diodes, and their own bias circuits. Therefore, the proposed active-passive reconfigurable antenna achieves a total bandwidth spanning from 70 MHz to 7200 MHz with a reflection coefficient consistently below -10 dB, and validated by experiments. Such wideband performance exhibits the exciting potential for multiple-standard signal sensing to support increasing wireless services with single antenna configuration.