Abstract: An opto-electronic antenna system includes a plurality of transmitting/receiving antennas disposed over a presecribed geometric surface such as a sphere. The antenna units are scanned electronically according to their position on the geometrical surface by supplying to the individual units, signals differing in phase in accordance with the position of the antenna with which the units are associated both in the vertical and horizontal directions. An evaluation circuit is provided for determining the direction of received radiation. The antennas are constructed of a multitude of lens elements having a hexagonal shape. By suitable design, a surveillance radar system is constructed.