Interference signal cancellor with active tunable notch filter

An interfering signal canceller for cancelling an interfering signal component of an input signal, having a predetermined band of frequencies, from a desired signal component of the input signal, wherein the input signal is fed to a primary path and an auxiliary path, the interfering signal canceller comprising:

• a voltage sensor element disposed in the primary path and fed by the input signal;
• a coupler disposed in the primary path and fed by the voltage sensor element;
• a Hartley image-reject element disposed in the auxiliary path and fed by the input signal for converting the input signal to an intermediate or baseband frequency signal wherein the Hartley image-reject element comprises:
• a pair of mixers each having an output;
• a pair of amplifiers, each having an input and an output, the input connected to a respective output of the pair of mixers;
• and
• a polyphase filter having two inputs and an output, the two inputs fed be a respective one of the outputs of the pair of amplifiers, the output of the polyphase filter providing the output of the Hartley image-reject element;
• a phase slope compensator disposed in the auxiliary path after the Hartley image-reject element to phase adjust an interfering signal component of a converted input signal;
• an inverse Hartley image-reject element disposed in the auxiliary path after the phase slope compensator to convert the passed the interfering signal component to the predetermined band of frequencies and having an output fed to the coupler.