A continuously tunable linear phase filter having a ground connection includes a three-terminal Bessel filter having an input terminal for receiving a signal, an output terminal for delivering a signal, a control terminal for receiving a control voltage, and a varactor. Each of the terminals are in signal communication with each other and the varactor is in signal communication with each of the terminals and ground, the varactor being responsive to the control voltage at the control terminal. The capacitance of the varactor is continuously adjustable in response to a change in the control voltage at the control terminal, thereby enabling continuous tuning of the continuously tunable linear phase filter in response to the control voltage.