Dual Image Dielectric Guide (DIDG) for Polarization Diversity Applications at Millimeter Wave Frequency

In this paper, a dual polarized dielectric waveguide is proposed for polarization diversity applications in millimeter wave frequency. The waveguide consists of a squarish dielectric slab attached to two orthogonal vertical and horizontal conductor walls. These walls act as image planes resulting in dual polarized mono-mode region with same propagation constant for $E^{y}_{11}$ and $E^{x}_{11}$ modes. Additionally, two sets of planar transitions exploiting the conductor walls are designed to excite the orthogonal modes as well as provide hybrid circuit integration. The transitions band Width is 3GHz covering 27 to 30 -GHz Millimeter wave frequency band. Measured insertion loss of the proposed guide integrated with transition in each side is around 2.7 dB. Isolation between the two orthogonal modes is measured better than 15 dB. Simulated and measured propagation constant of the proposed guide are matched.