Abstract: A tunable filter includes at least two tunable resonators, a resonator comprising at least one inductance or transmission line, the inductance or transmission line having a first end connected to the ground M and a second end coupled to another resonator via a coupling impedance, and several switched capacitors, wherein the inductance or transmission line comprises several access points or connection points distributed along the inductance allowing for the connection or non-connection of a switched capacitor whose value is defined as a function of its position on the inductance, the capacitors of low weights are situated close to the end of the inductance linked to the ground M. A use of the filter in radio transceivers is also provided.

Abstract: The invention relates to a radio communication terminal (10) comprising: an antenna (12) having an impedance; an impedance-measuring sensor (14) for measuring the impedance of the antenne (12) in order to produce a measured impedance; an amplifier (18); a filter (20) connected to the antenna (12) and the amplifier (18), the filter (20) having a variable impedance; and a body (22) for controlling the impedance of the filter (20), the body being used to control the impedance of the filter (20) according to the measured impedance.