Image Dielectric Guides based Crossover for Millimeter-Wave Applications

This paper presents an IDG-based crossover for the first time. The isolation of the two channels has been significantly improved by increasing the widths of the IDGs in the region approaching the channel intersection. Due to the very simple structure, the proposed crossover is fabricated just with a 3D printer and copper tapes. Results exhibit that with a simulated insertion loss (S21 and S43) of 1.6 dB, the proposed crossover exhibits an ultra-wide bandwidth of 17.51 GHz (27–44.51 GHz). Over this bandwidth, the isolation between the two RF channels and the return loss of the ports are more than 20 dB. The group delay dispersion is very small compared to the other crossovers with a deviation of only 0.04 ns over the frequencies of operation. The wider bandwidth, simplest structure, improved isolation of channels over the entire bandwidth, and good impedance matching emphasize its use in millimeter-wave applications.