Studies of the Adcock direction finder in terms of phase-mode excitations around circular arrays

A new analysis of the Adcock direction finder is presented in terms of phase-mode excitations associated with circular arrays. This leads to a convenient form of processing for such a d.f. system based upon a circular array/Butler matrix configuration which employs a direct phase-measuring detector for bearing measurements. The principal sources of error limiting the physical spacing of elements within the array are highlighted and methods of improving wide-bandwidth operation are presented which entail the use of directional elements. A signal processing system based around a small microcomputer is discussed for the automatic compensation of errors due to the finite number of elements.