Switchable edge-line coupler based on parity time-reversal duality symmetry

Area of Science:

• Electromagnetics and Wave Propagation
• Metamaterials and Metasurfaces
• Microwave Engineering

Background:

• Parity Time-reversal Duality (PTD) symmetry offers unique wave propagation properties.
• Conventional couplers face limitations in matching and directionality.
• PTD bifilar edge lines (BELs) provide backscattering-protected propagation.

Purpose of the Study:

• To design, construct, and measure a compact broadband Edge-Line Coupler (ELC) based on PTD symmetry.
• To leverage PTD-BELs for enhanced coupler performance.
• To demonstrate intrinsic port matching and controlled signal rerouting.

Main Methods:

• Conception and design of a 4-port junction utilizing PTD symmetry.
• Integration of a mushroom metasurface for Perfect Magnetic Conductor (PMC) boundary conditions.
• Implementation of a switch circuit to control signal routing via open/short conditions.

Main Results:

• The fabricated ELC prototype exhibits intrinsic port matching.
• The coupler demonstrates strong coupling with one port, strong decoupling with another, and weak coupling with a fourth.
• Measurements confirm good directionality across a broadband frequency range (24-30 GHz).

Conclusions:

• The PTD-based ELC offers a compact and broadband solution for microwave circuits.
• PTD symmetry enables robust wave propagation and controlled coupling.
• The device shows potential for applications requiring efficient signal management.