Isolation Enhancement Between Waveguide Slot Arrays Using Quasi-Gap Waveguide Structure

This work presents a metamaterial structure to improve the isolation between two linear slotted waveguide arrays. The proposed decoupling structure consists of two columns of metal pin arrays that can suppress surface wave propagation. Also, the resulting structure only takes up a small space between the radiating slots of the two arrays. Simulated results show a 5 dB improvement in the inter-element isolation without a significant impact on the antenna radiation performance. Moreover, the reflection coefficient bandwidth can be slightly increased.