PCB Spiral Antenna Feed Network for ELINT

The patent replaces the mechanical cavity-backed structure with a planar PCB-based spiral antenna design. The spiral antenna is fabricated directly on the PCB substrate using standard PCB manufacturing techniques, eliminating the need for bulky cavity structures and manual assembly. This substitution maintains electrical performance while dramatically reducing size and enabling conformal mounting on flat surfaces.

The patent integrates the antenna, feed network, and ground plane into a single PCB assembly. The spiral antenna element, feed lines, impedance matching components, and ground references are all fabricated on the same PCB substrate, creating a compact integrated structure that eliminates the need for separate cavity components and reduces overall antenna volume.

The patent replaces expensive manual hand-assembly processes with automated PCB fabrication. The spiral antenna is created using standard PCB manufacturing processes including copper etching, lamination, and drilling, which are highly automated and scalable. This eliminates labor-intensive hand assembly while maintaining consistent electrical performance across production batches.

The patent changes the manufacturing approach from custom hand-assembled components to standard PCB fabrication parameters. By specifying antenna dimensions, trace widths, and material properties in terms of standard PCB manufacturing capabilities, the design enables cost-effective production through automated processes while maintaining the required VSWR and gain performance specifications.

The patent combines the antenna structure with a flat PCB substrate, creating a planar configuration that can conform to flat mounting surfaces. The integrated design includes the spiral element, feed network, and ground plane all on the same substrate plane, enabling the antenna to be mounted conformally on aircraft skins, vehicle bodies, or other flat surfaces while maintaining electrical performance.

The patent replaces the three-dimensional cavity-backed mechanical structure with a two-dimensional PCB-based design. This planar configuration eliminates the depth and bulk of traditional cavity antennas, allowing the antenna to lie flat against mounting surfaces and conform to the underlying structure while achieving the required VSWR and gain patterns through optimized PCB trace geometry.