PURPOSE: To shorten computing time by preventing the fault of a transmission/ reception module due to interconnection from being generated by calculating a phase setting value for an element antenna group designated at a control element designation circuit with limitation by a non-linear optimization method.

CONSTITUTION: In case of forming the zero point of a radiant pattern in the arrival direction of an unrequired wave, the control element designation circuit 10 selects only the element antenna group 1 in the peripheral part of an antenna aperture. Also, it is limited only to the element antenna group included in a certain area in the group 1 arranged in two-dimensional shape for the incident direction of a wave. A control processor 8 calculates a phase value only for the antenna group in the area by the non-linear optimization method, and performs the setting of the phase value on each phase shifter via a phase shifter control part 7, and forms the zero point of the pattern. Since the arrangement of the antennas in the area is performed coarsely, the fault due to the excessive wave of the transmission/reception module 2 by the interconnection can be prevented from being generated, thereby, the computing time of the phase value can be shortened.