Electronically Tunable Antenna Pair and Novel RF Front-End Architecture for Software-Defined Radios

This paper proposes a novel RF front-end architecture for software-defined radios (SDRs) based on an electronically tunable antenna pair controlled by an antenna control unit (ACU) consisting of field effect transistor (FET) switches and a field programmable gate array (FPGA). The fundamental gain-bandwidth limitations of electrically small antennas prevent a small antenna from having high efficiency and wide bandwidth simultaneously. In the age of miniaturization, especially in the wireless communication industries, a promising solution to this limitation is to introduce reconfigurable antennas that can be tuned electronically to different frequency bands with both high efficiency and narrow instantaneous bandwidth. This reconfigurable antenna technology not only simplifies current RF front-end architectures, but can be reprogrammed on demand to transmit and receive RF signals in any desired frequency band. This novel RF front-end architecture implemented by a reconfigurable antenna pair can help realize SDRs.