A frequency tunable filter and an associated apparatus are provided, where the frequency tunable filter may include a plurality of ports including an input port and an output port, and may further include an inductor-capacitor (LC) resonator, a switching unit that is coupled between the LC resonator and a ground terminal of the frequency tunable filter, and a resonance adjustment unit that is coupled between the LC resonator and the ground terminal. For example, the LC resonator may include a first terminal coupled to each of the input port and the output port, and may further include a second terminal, the switching unit may selectively provide a conduction path between the second terminal of the LC resonator and the ground terminal, and the resonance adjustment unit may selectively change a resonance characteristic of the LC resonator.