PURPOSE: To accurately evaluate a shielding performance by forming an opening in which a tester of the size of the original can be mounted in a partition wall between a transmission chamber and a reception chamber with a radio wave absorbing material as an inner wall of a radio wave shielding material, and forming a chamber in which a transmitter and a measuring instrument required for manual labor in the exterior.
CONSTITUTION: An element 15 to be tested of a member of a building of the size of the original is conveyed from an openable door 9 into a transmission chamber 2, and mounted at a mount 17 formed at the periphery of an opening 16. Transmission power responsive to the radio wave of a desired frequency is selected by a transmitter 18 of a transmitter chamber 5, supplied to a transmission antenna 10 to radiate the radio wave. A radio wave absorber 8 is provided at the periphery of the antenna 10 to propagate only the wave to be directly radiated from the antenna 10 to the element 15 to be tested. Only the leakage radio wave to be transmitted through the element 15 to be tested is received at 3 through the element 15 to a reception antenna 13 of a reception chamber 3 by a radio wave absorber 12, the received power is supplied to the radio wave shielding performance evaluator 19 of a measuring chamber 6 to evaluate the radio wave shielding performance of the element 15 to be tested. Thus, it can prevent a measuring error from occurring due to reflected wave or a human body.
SAWADA AKIRA
YOSHINO RYOJI
