Full Band Compact Power Arm Subsystem With High Directive Sample

An output arm is the first subsystem in the microwave components chain connected immediately after the power amplifier. These arms are responsible for transferring the signal from the output port of the power amplifier to the standard line of the system. The second objective is to obtain directive samples for both forward and backward signals. The typical design process for such a subsystem is carried out through the design of separate components, independently. This limits the achievable performance of the entire system and introduces excessive losses at intermediate flanges. In this work, we present a novel approach to design such a subsystem using a global optimization procedure. Specifically, we address both compactness and full-band operation of output arms deployed in radar applications. Analysis and design of each component in the proposed subsystem are illustrated. The presented subsystem achieves a deep matching level of 19 dB within an overall length below 2λ
_g
. Moreover, the directive sample obtained through the presented design has an ultra-flat response of 20 dB ± 0.5 dB over the entire band of operation, while the directivity of the samples exceeds 18 dB. The measured results of the fabricated prototype have an excellent agreement with the simulations.