A W-band, Wideband, and Low-Loss Slot-Coupled Multi-Layer Transition with Compact Leakage-Suppressing Scheme

This paper proposes a compact and cost-effective solution for high-integration packaging through a W-band slot-coupled transition between the top and bottom substrate integrated waveguides (SIWs), incorporating a leakage-suppressing scheme for the bonding layer. To address this issue, a double-sided mushroom-like electromagnetic band gap (EBG) structure is used to implement leakage suppression caused by TEM polarization waves in the bonding layer between two substrates. Finally, a back-to-back transition is fabricated and measured, achieving a relative bandwidth of 16.2% at W-band with insertion loss less than 1 dB.