Design and Architecture Selection of Corporate Feeds Comprising Equal-Split Power Dividers for Low-Sidelobe Arrays

This paper overviews the process of prototyping of corporate feeds for excitation of linear arrays of low sidelobe broadside sum patterns. Although the corporate feeds of interest produce non-uniform in-phase excitation tapers at their outputs, they comprise only equal-split power dividers and thus shorten the feed implementation stage, simplify the corporate feed composition, and reduce sensitivity of the feed elements to tolerances of manufacturing and material parameters. A summary of the selected results with the emphasis on low sidelobe levels is presented. The levels are computed using the array factor and provided for feeds driving linear arrays of up to thirty elements. It is should be emphasized that the array characteristics at the feed prototyping stage are irrelevant to the feed-array implementation technology and, in this sense, are similar to characteristics of filters' prototypes. The outline of the dedicated software package developed in Matlab used for feed prototyping is overviewed. An example of feed implementation in microstrip technology with electromagnetic simulations for the upper part of the K-band is presented. The considered class of corporate feeds as well as the feed prototyping tool considered in this work can contribute to the development of cost-and performance-efficient communication solutions for sub-mm wave and mm-wave frequencies.