SBIR/STTR Award attributes
High-speed and reliable tactical communications have empowered the Air Force with overwhelming information superiority, and control of the battlespace. However, the effectiveness of such systems has been impacted by the increasingly congested and contested spectral environment, compounded by the reliance on half-duplex systems. The latter rely on time- or frequency-division to separate transmit and receive operation, resulting in reduced spectral efficiency and throughput. Simultaneous Transmit and Receive (STAR) would enable full-duplex operation, doubling data throughput and spectral efficiency. Current techniques have demonstrated only limited isolation and bandwidth and struggle to prevent coupling of non-linear harmonics and noise from the transmitter. The proposed approach produces unprecedented suppression of coupled self-interference (including harmonics and noise) at the antenna and RF stage, enabling full duplex operation. Our technique leverages three stages of cancellation to achieve >110dB isolation over multi-octave bandwidth: 1) high isolation multi-port antennas, 2) self-interference cancelling RF filters, and 3) digital linear and non-linear signal suppression.
