Log-domain filter having a variable dynamic range window

摘要

A filter system having a variable dynamic range window comprising a parameter detector, a biasing unit and an active filter network. In one implementation, the active filter network comprises a log-domain filter. The parameter detector is configured to detect a parameter of a signal. The biasing unit, responsive thereto, biases the incoming signal. In one implementation, the biasing unit biases the signal to avoid zero crossings thereof. The effect is to adjust the dynamic range window of the filter to achieve an effective dynamic range which is greater than the nominal dynamic range.