Phased Array Antenna Asymmetric Coupling Structures

The patent applies asymmetry by placing different asymmetric scatterers at different locations within the unit cell. Each scatterer has a specific geometric asymmetry that creates different coupling characteristics to adjacent antenna elements. This asymmetric configuration prevents the coupling terms from adding coherently, thereby reducing the overall coupling effect while maintaining half-wavelength element spacing for wide scanning capability.

The patent converts the harmful coupling effect into a beneficial feature by using asymmetric scatterers to create controlled, non-coherent coupling. Instead of trying to eliminate coupling entirely, the asymmetric configuration transforms the coupling terms into a form that does not degrade ARC performance, allowing half-wavelength spacing to be maintained without the harmful coherent addition of coupling terms that would cause grating lobes.

The patent deliberately introduces asymmetry in the coupling structures (asymmetric scatterers) to prevent coherent addition of coupling terms. While this increases manufacturing complexity compared to symmetric structures, it dramatically improves ARC performance by eliminating the coherent coupling effect. The asymmetry is carefully designed to create different coupling paths that do not reinforce each other.