Wideband vector modulator for RF cancellers in STAR systems

Wireless communications can benefit from Simultaneous Transmit and Receive (STAR) functionality by providing unprecedented access to spectrum previously considered unavailable due to self-interference (SI). Several techniques have recently been developed to mitigate SI and enable this new modality, including the use of RF cancellers comprised of vector modulator devices. This paper introduces a wideband vector modulator prototype that operates over a 4:1 bandwidth, specifically 1.5 to 6 GHz, and was found to have 12.7 and 15.4 dB of insertion loss at 2.45 and 5.8 GHz, respectively. This device can provide future STAR systems with dynamic tunability to make them feasible for inclusion in advanced cognitive wireless networks.