There is provided a dual-band converter operable to convert a first RF signal in a first frequency band and a second RF signal in a second frequency band that is separate from the first frequency band into a DC signal for powering a load. The converter comprises: a rectifier arranged to generate, based on the first and second RF signals, the DC signal and two or more harmonics of each of the first and second RF signals during operation of the dual-band converter; a planar transmission line arranged to guide the first and second RF signals to the rectifier and to receive a component of each of the harmonics generated by the rectifier during operation of the dual-band converter; a first stub and a second stub each connected to the planar transmission line and arranged to reflect, during operation of the dual-band converter, a component of a first harmonic and a component of a second harmonic of the first RF signal received from the rectifier, respectively; and a third stub and a fourth stub each connected to the planar transmission line and arranged to reflect, during operation of the dual-band converter, a component of a first harmonic and a component of a second harmonic of the second RF signal received from the rectifier, respectively.