Wideband investigation and characterization of wave-propagation on polymer microwave fibers at sub-THz frequencies

Abstract Using polymer microwave fibers as waveguides has attracted significant attention over the last years. They are an attractive replacement for optical fibers or copper wires due to their price, flexibility, and robustness against electromagnetic interference. This work investigates the behavior of the wave propagation of a circular-shaped polymer microwave fiber mathematically and provides wide-band measurement results. The mathematical model is completely analytical and does not need any 3D finite element method simulation. After a short theoretical introduction, we compare the theoretical results with measurements performed by a vector network analyzer from 20 GHz up to 150 GHz. The behavior of the propagation constant, propagation speed, and group delay are compared with the predicted results. The maximum relative error between the theoretical prediction and the measurements was less than 0.7%.