High Isolation Substrate Integrated Waveguide Passive Front-End for Millimeter-Wave Systems

A substrate integrated waveguide passive front-end is investigated and developed for low-cost and high isolation millimeter-wave applications. The system makes use of two uniformly excited 2times4 slot array antennas to create a dual-antenna platform for full-duplex systems. Measured antenna-to-antenna isolation is over 48 dB when the two antennas are placed along the same longitudinal axis. Two dual-mode SIW filters are also integrated to further increase the isolation up to 60 dB. Moreover, this system is not sensitive to the environment when obstacles are located more than 2 meters away