US Patent 7466287 Sparse trifilar array antenna

An array antenna is arranged in an innovative sparse trifilar configuration. The antenna elements forming the array antenna are arranged to form three non-linear arrays. The antenna elements are approximately aligned to a triangular lattice structure with the antenna elements of each non-linear array occupying adjacent lattice positions. The three non-linear arrays are separated from each other by vacant lattice positions, thereby making the configuration a sparse array.