Mixed-Protrusion Waveguide Transition for Broadband Radar Antennas

The transition structure is divided into multiple substrates (first substrate, second substrate, third substrate) with distinct functions. The first substrate contains waveguide structures for broadband transmission, the second substrate provides antenna elements, and the third substrate serves as a transition layer with protrusions. This segmentation allows each layer to be optimized independently while working together to achieve broadband performance without excessive overall complexity.

The patent implements a nested multi-layer structure where the first substrate with waveguide structures is positioned adjacent to the second substrate, with the third substrate transitioning between them. The protrusions from the third substrate nest into corresponding recesses in the second substrate, creating a compact integrated assembly that reduces the overall transition unit complexity while maintaining broadband capabilities.

The patent employs asymmetric protrusion structures where the third substrate has protrusions with specific height variations and positioning. Some protrusions are taller than others, and they are strategically positioned to provide mechanical support at critical locations while minimizing parasitic electromagnetic effects in the broadband frequency range. This asymmetric design allows optimization of both mechanical stability and electromagnetic performance.

The patent uses multiple identical protrusion structures distributed across the third substrate. By replicating the same geometric design across multiple locations, the structure achieves uniform mechanical support while the distributed arrangement minimizes localized parasitic effects. The consistent geometry across all protrusions allows for predictable electromagnetic behavior across the broadband frequency range.