An Integrated, Phase-Controlled Power Divider for Metasurface Array Antennas

TL;DR

This paper introduces a phase-controlled power divider for metasurface array antennas, enabling equal power distribution and phase control in a compact, robust, and high-power capable design suitable for microwave applications.

Contribution

The paper presents a novel, mechanically robust power divider design using hollow waveguides and metamaterial irises, capable of precise phase control for metasurface antennas.

Findings

Achieves uniform power distribution to all array elements.

Provides prescribed phase shifts to mitigate grating lobes.

Design is lightweight, low-cost, and suitable for high-power microwave applications.

Abstract

We present the design of a phased, modulated, power distribution network for metasurface array antennas. The specific metasurface array design comprises a series of waveguides, each feeding a sub-array of dynamically tunable metamaterial elements that radiate at microwave (X-band) frequencies. To remain a one-port device, the composite array requires a power divider that can excite each branch waveguide with equal power. Further, the power divider must also apply a prescribed phase shift to each branch waveguide to mitigate metasurface-specific grating lobes. The presented design features hollow metal waveguides, with a conducting sheet patterned with metamaterial irises serving as the upper wall. A single hollow metal main waveguide feed is used to couple power to each of the branch waveguide. Carefully oriented slots control both the magnitude and phase of the field distributed from the main feed to each branch. All waveguides can be machined from a single block of metal, with a metamaterial-patterned printed circuit board laminated to the top of the assembly. The resulting design is mechanically robust and capable of high power operation while retaining the low-cost, low-power consumption, lightweight, and low-profile features common in metasurface antenna designs.