Design Approach and Comparison of Phase Shifter Performance in DOA Estimation System

The paper outlines three types of phase shifter networks utilized in phased array antennas for direction-of-arrival estimation. It compares the mechanical rotation method of antenna array with Butler matrix-based and software-controlled phase shifter networks. Performance metrics such as phase shift accuracy and response time were considered. Comparisons were made between simulation and measurement results of Butler matrix and software-controlled networks. The mechanical rotation system operates as an open-loop system, while the other two can function as closed-loop systems.