Adaptive narrowband interference rejection for satellite navigation receiver

A receiver system with interference rejection, the receiver system comprising:

• an antenna for receiving a radio frequency signal;
• a downconverter for converting the radio frequency signal to an intermediate frequency signal;
• an analog-to-digital converter for converting the intermediate frequency signal or analog baseband signal to a digital baseband signal;
• a selective filtering module for filtering of the digital baseband signal consistent with a target receive bandwidth;
• a narrow band rejection filter for rejecting an interference component, wherein the selective filtering module comprises:
• an adaptive notch filter supporting an infinite impulse response mode;
• and
• a controller for controlling the adaptive notch filter, the controller configured to execute a Steiglitz-McBride (SM)-modeled estimator or a least mean squares algorithm estimator to estimate filter coefficients of the adaptive notch filter, or both the Steiglitz-McBride (SM)-modeled estimator and least mean squares (LMS) algorithm estimator, the SM-modeled estimator or least mean squares algorithm estimator being storable in a data storage device and the controller configured to adjust recursively the filter coefficients of the adaptive notch filter based on the estimated filter coefficients, wherein the adaptive notch filter comprises a pre-scaler that is configured to apply a pre-scale to pre-emphasis filtering or adaptive line enhancer (ALE) module to reduce the logic size of a digital data processing system.