A study on RF characteristics of polyether sulfone substrate for application to flexible mobile communication device

In this work, coplanar waveguide was fabricated on flexible PES substrate, and their RF loss characteristics were extracted using transmission line theory. Concretely, several Q-factors of the coplanar waveguides were extracted using transmission line theory. Firstly, Q_L was characterized using the equivalent RLGC circuit. According to measured result, the Q_L was 25.7 at 49.8 GHz. Q-factor was also extracted from a resonant tank built using a one-quarter of a wavelength long line at the resonance frequency f₀. According to the measured result, the Q-factor measured from one port open stub resonant circuit was 38.3 at a resonance frequency of 49.8 GHz, which was much higher than the open stub on silicon substrate.