Self-phasing array antennas

A self-phasing array antenna is described which operates on the incident wavefront in such a manner that when it is retransmitted it returns whence it came as a coherent wavefront irrespective of the original phase distribution incident on the array. Self-phasing is useful where a two-way propagation path is available and where a conventional antenna cannot operate efficiently because of an unknown phase distribution in the incident wavefront. The operation of a self-phasing array, its properties, its relation to other antenna design techniques and its potential applications are discussed.