Design and Analysis of a Butler Matrix at 60 GHz Compatible with Metallic-Nanowire-Filled Membrane Fabrication Platform

This work describes the design and analysis of a 4 x 4 Butler matrix for applications in the 60 GHz unlicensed frequency band. Each of the constitutive blocks that make up the network - hybrid coupler, crossover, and phase shifter - were designed to be compatible with metallic-nanowire-filled membrane manufacturing process and optimized separately. Simulations were conducted using Ansys HFSS and improvements to the devices' behaviours were achieved through parametric analysis. A complete design was obtained by connecting all primary devices and each output port was connected to a series patch antenna array. The complete Butler matrix analysis revealed a device that produces the expected phase distribution and radiation at the desired angles.