PURPOSE: To measure a radiation pattern over a wide solid-angle range by providing a holder and a rotary mechanism.

CONSTITUTION: When a body 1 to be measured receives an electromagnetic wave sent by an antenna 5 for measurement, the rotary mechanism 4 varies the angle of the body 1 to be measured and measures the reception intensity of the body 1 to be measured to check reception pattern characteristics of the antenna as the body 1 to be measured. Further, the holder 2 is a spherical shell which is made of a nonmetallic material and has an axis 3A as its major axis, the body 1 to be measured is held by a support part 2A nearby the center of the cavity part of the spherical shell, and the mechanism 4 blows force feed air which is inputted from a spiral air hose 4A out of the blowout hole of a holder receiving pan 4C above a perpendicular axis 4B to rotate the holder 2 around the axis 3A. Further, the mechanism 4 is mounted on the rotary disk 6A of a rotary seat 6 and rotated around the axis 3B. Then the force feed air is inputted from the hose 4A and deforms following up the rotation of the rotary disk 6A. Further, the height of the perpendicular axis 4B is increased so as to evade the influence of electromagnetism generated by the motor driving of the rotary seat 6.