A Millimeter Wave High Isolation Resistive Coupler In 45nm RFSOI Technology for Sensing Application

This paper proposes the design and test of a high isolation millimeter wave directional coupler for sensing application. The compact device is fabricated using the 45nm RFSOI technology of Global Foundries. The core size of the coupler is 44 mu m x 34 mu m. An insertion loss close to the expected 3.6 dB and a coupling ratio of about 26 dB within the 40-80 GHz frequency band have been reached. Moreover, the proposed coupler achieved a measured isolation greater than 43 dB at 60 GHz. This performance is particularly mandatory in sensing applications where maintaining the integrity of the measured signal is critical.