Block adaptive filtering with application to real-time broadband RF spectral whitening

The frequency content of signals, which can be adaptively processed in real time, have typically been limited by A/D conversion rates and digital signal processor instruction speeds. By sampling averages rather than instantaneous values of signals formed from the predictor configuration, A/D sample rates and computational requirements can be significantly reduced. This paper describes a circuit which adaptively attenuates 90 MHz bandwidth signals with a 25 kHz sample rate using an analog programmable transversal filter (PTF). The dynamic range of the overall circuit exceeds that of the individual PTF.