Adaptive filter device and method for providing an output signal

A receiver for a radio frequency signal, the receiver being realized as a Global Navigation Satellite System (GNSS) receiver, or a receiver for wireless communication, the receiver comprising an adaptive filter device that includes:

• a detector circuit;
• a delay circuit;
• a tracker circuit;
• and
• a notch filter circuit,
• the detector circuit configured to receive an input signal, to detect a presence of a sweeping interference in the input signal, and upon detection of such sweeping interference to provide a first trigger signal to the delay circuit, wherein the first trigger signal comprises a first frequency indication,
• the delay circuit configured, upon receiving the first trigger signal, to provide a second trigger signal to the tracker circuit after an adjustable amount of time, the second trigger signal having a second frequency indication, which is derived from the first frequency indication,
• the tracker circuit configured to receive the input signal or a delayed version thereof and further configured, upon receiving the second trigger signal, to estimate a frequency of the sweeping interference using the second frequency indication, to track the estimated frequency and provide the estimated frequency as a third frequency indication to the notch filter circuit, and
• the notch filter circuit configured to substantially eliminate the sweeping interference from the input signal using the third frequency indication and therefrom provide an output signal, wherein the delay circuit is further configured to initialize the tracker circuit during the adjustable amount of time.

A method for providing an output signal comprising:

• receiving an input signal,
• detecting a presence of a sweeping interference,
• providing a first trigger signal upon detection of such sweeping interference, wherein the first trigger signal comprises a first frequency indication,
• waiting for an adjustable amount of time and then providing a second trigger signal having a second frequency indication, which is derived from the first frequency indication,
• during the adjustable amount of time, initializing a tracker circuit,
• estimating, by the tracker circuit, a frequency of the sweeping interference using the second frequency indication upon receiving the second trigger signal,
• tracking, by the tracker circuit, the estimated frequency and providing the estimated frequency as a third frequency indication, substantially eliminating the sweeping interference from the input signal using the third frequency indication and therefrom providing the output signal.