Wideband Antenna Systems

Antennas are important for Simultaneous Transmit and Receive (STAR) systems. They are on the front-line of self-interference suppression chain contributing to the first 30dB+ of TX to RX isolation and prevention of LNA suppression. In this talk, we first review the role of antennas for in-band full duplex (IBFD) communications, and then discuss various approaches for achieving STAR antenna systems over wide instantaneous bandwidths from UHF through mm-wave frequencies. Emphasis is on approaches that eliminate the need for (1) bandwidth/power/isolation/losses limited circulators, and (2) manipulation of antenna’s space nature, specifically polarization and beam-pointing multiplexing. Stand-alone antenna systems capable of achieving more than 50dB isolation over multi-octave bandwidths with directive or omnidirectional coverage are discussed. High and low-power configurations with associated tradeoffs and possible applications in direction finding and other applications are also reviewed. We introduce hybrid apertures that operate over >200:1 instantaneous bandwidth with TX powers in excess of 50dBm. Novel mm-wave solutions including lenses, arrays, and reflectors are also reviewed. In summary, this work shows that the diverse IBFD antenna solutions are needed and feasible for modern and future commercial and defense STAR systems across the spectrum.