Forked Dipole Antenna Shrouds for Beam Stability

The dipole radiating element is divided into multiple separate dipole arms (first and second dipole arms for each polarization) instead of using a single integrated element. This segmentation allows independent optimization of each arm's geometry and positioning, enabling dual polarization functionality while maintaining stable beam width characteristics through precise control of each segment's contribution to the overall radiation pattern.

Each dipole arm is given specific local geometric characteristics (different lengths, orientations, and positions) tailored to its function. The first and second dipole arms have distinct local qualities that enable them to radiate in specific polarizations while maintaining overall beam width stability. This local differentiation allows optimization of each arm's radiation pattern to compensate for potential beam width variations.

The high band dipole radiating elements are physically extracted and positioned in separate columns away from the low band radiating elements. This spatial extraction removes the source of resonance interference from the low band operating region, allowing high band elements to resonate at their intended frequencies without creating harmful interference in the low band frequency range.

The antenna structure transitions from a planar two-dimensional arrangement to a three-dimensional configuration with multiple columns and rows. High band elements are placed in separate columns at different spatial positions and orientations relative to low band elements. This dimensional separation in space and orientation prevents resonance coupling between bands while maintaining multi-band functionality.

Adjacent radiating elements are separated not only in the horizontal plane but also in the vertical dimension and through angular orientation. Elements are arranged in multiple rows and columns with specific spacing and tilt angles, creating three-dimensional separation that maintains compact overall footprint while ensuring sufficient isolation between adjacent elements to prevent mutual coupling and interference.

The arrangement of radiating elements employs asymmetric positioning and orientation rather than uniform symmetric placement. Different rows and columns have elements at varying distances, angles, and heights from each other. This asymmetric configuration optimizes isolation between adjacent elements while maintaining compact dimensions, as each element's position is specifically tailored to minimize coupling with its neighbors.

The dipole structure is segmented into multiple arms with specific geometric configurations rather than using simple conventional single-element dipoles. Each arm is designed with precise dimensions and orientations to control the polarization characteristics. This segmentation enables better cross-polarization rejection while maintaining manufacturing feasibility through standardized fabrication processes for each arm type.

The geometric parameters of the dipole arms (lengths, widths, spacing, orientations) are optimized to specific values that improve cross-polarization performance. By carefully controlling these parameters, the radiation patterns achieve better polarization purity and cross-polarization isolation. These parameter optimizations can be implemented through standard manufacturing processes, balancing performance improvement with manufacturing ease.