METHOD AND APPARATUS FOR COMPENSATING FOR CLICK NOISE IN AN FM RECEIVER

摘要

These and other objects of the present invention are achieved using an Adaptive Multi-Path Filter (AMPF) which eliminates audibly objectionable click noise generated at the output of an FM discriminator to prevent audible distortion or other corruption of the desired signal which may include voice and low speed digital data. Clicks are detected at the discriminator output using a colored-noise, matched filter designed and adapted to the click signature/shape as well as to the desired signal characteristics. The colored-noise matched, filter output is then compared to an adaptive threshold. When the threshold is exceeded, a click is registered as detected. Click duration is then estimated. An estimate of the desired signal is generated and that replaces the originally received data signal estimate within the click duration region. Using characteristics of the desired signal just before and after the detected click noise, the adaptive filter accurately estimates the parameters of the desired signal so that the replacement signal fairly models what the desired signal would have looked like had the click not occurred. In this way, a substantial portion of the desired signal is preserved.