Analytical Approach to Microwave Orientations Based on a Strongly Coupled Array

With the rapid progress of radio frequency (RF) and baseband integrated circuits, there are strong demands to minimize the dimension of array-based microwave systems, including orientation systems. However, miniaturizing array apertures will result in strong mutual coupling. To date, realizing microwave orientations in the presence of strong mutual coupling remains a technical challenge. In this article, we theoretically analyzed and experimentally demonstrated that this challenge can be overcome by deriving forward equations based on a hybrid equivalent circuit model and solving such equations by a backpropagation optimization. Different from conventional circuit equivalence, this hybrid equivalence integrates the modeling of incident fields, coupled array, and RF channels. Full-wave simulations and experiments based on a visualized UHF-band prototype verified the effectiveness. This approach can be further used in coupled array-based beamsteering, forming, and nulling applications.