Investigation and design of novel spatial power combiner

Abstract

This project aims to create a novel spatial power combiner. The design utilizes the broadband techniques and EBG ground-slot structure to enhance the bandwidth and the out-of-band stability. A broadband ground-slot coupling technique is proposed and implemented on Design 1. This prototype can achieve 40% gain bandwidth at 5GHz centre frequency. The Tee-junction coupler in Design 1 is subsequently modified and the final bandwidth is increased to 52%. To achieve a greater performance, the direct signal coupling technique and the EBG hole structure are proposed and verified through the circuit-feed spatial power combiner prototype. The measurement results show that it can achieve more than 90% impedance bandwidth and is also stable from 0.5GHz to 20.5GHz.