RECEIVE SIDE PULSE WIDTH CONTROLLED ADAPTIVE EQUALIZER

摘要

Pulse width controlled adaptive equalizers (14) are provided for telecommunication signals which are routed over coaxial cables. The adaptive equalizers operate on the premise that a coaxial cable degrades a telecommunication signal by widening the pulse of the signal and decreasing the amplitude. The longer the cable is, the wider the pulse gets. Thus, by detecting the width of the pulse against a desired width, and feeding back the difference to a variable filter which can correct the pulse width, a pulse width controlled adaptive equalizer can be provided. The preferred pulse width controlled adaptive equalizer includes: a variable filter block (20a, 20b) for filtering input signals to provide frequency dependent gain based on the amplitude of a control signal; a comparator block (26a, 26b) for comparing the filtered bipolar signal against a reference value based on the peak amplitude of the signal to provide a pulsed output; a pulse width detector (32) which senses the pulse width of the pulsed output and outputs a signal indicative of the pulse width; and a feedback filter (34) which filters the signal indicative of the pulse width and provides a control signal to the variable filter in order to control the frequency dependent gain of the filter.