Full mode substrate integrated waveguide type high power amplifier with second harmonic suppression

This article presents a 10 W full-mode substrate integrated waveguide-type high power amplifier. The matching circuit was designed with microstrip-to-SIW transition and SIW bandpass filter. To realize the matching network at the fundamental frequency 2.18 GHz, we used in the SIW bandpass filter an inductive metallized post. A full mode SIW band pass filter is applied to suppress the 2
^nd
harmonic of 2.18 GHz as input and output of the matching circuits. The insertion-loss measurement of the SIW bandpass filter at the frequency 2.18 GHz and 4.36 GHz are 0.86 dB and 34.58 dB respectively. The SIW HPA was designed and fabricated at the frequency of 2.18 GHz using GaN transistor. This measurement of power-added-efficiency at output of 40.02 dBm is 60.7% with a gain of 13.0 dB at the 2.18 GHz. For 4G Long Term Evolution (LTE) and 5G system in millimeter wave, this can be used with other SIW-type of passive circuits by integrating in same substrate.