Abstract: An attenuation device for variably attenuating an electromagnetic signal radiated by a microwave source includes a cylinder formed by a cylinder wall having a first flange and a second flange. The cylinder wall is closed at a first end thereof by the first flange and at a second end thereof by the second flange. The cylinder wall is pierced at the first end by a liquid inlet/outlet port and at the second end by an air inlet/outlet port. The attenuation device further includes a piston being arranged in the cylinder and being displaceable in the cylinder. The piston bounds with the first flange a variable volume filled with an electromagnetic energy absorbing liquid. The attenuation device further includes a displacement sensor for sensing a position of the piston the cylinder.

Abstract: The invention relates to a device for variably attenuating a radiated microwave signal, which comprises a variable volume tight cylinder (11) filled with an electromagnetic energy absorbing liquid and remote control means.