Design and Simulation of Fixed Physical Length Planar Spoof Surface Plasmon Polariton-mode Delay Lines for a 3-bit 360 degrees Phase Shifter for Terahertz Band

We present the design and simulations of a group of fixed physical length spoof Surface Plasmon Polariton based delay lines to compose a 3-bit 360 degrees phase shifter at 0.3 THz. The design is based on corrugated planar Goubau line (CPGL) delay sections with different corrugation depths varying between 19.25 mu m and 44.5 mu m. The simulations result in average phase error, insertion loss, and return loss of 3.265 degrees, -2.82 dB, and -26 dB at 0.3 THz through a delay section of 1.0575 mm and 1.5635 mm, respectively.