Direction Finding System Using Five-Element Circular Antenna Array Interferometer

This study analyzes both equal and unequal baseline structures and their phase ambiguity in a five-element circular antenna array interferometer direction finding system. Direction finding accuracy is improved through weighted processing of multi-baseline measurement data, with proposed methods for weight coefficient selection and signal processing algorithms including phase difference estimation, angle transformation, ambiguity resolution, and receiving channel error correction. Computer simulations demonstrate that both baseline structures achieve comparable accuracy, with maximum direction finding error below 0.10 across all directions in the ultra-short wave frequency band.