| 摘要 |
A physical layer device includes a cable tester that determines a cable status. A test module transmits a test pulse on the cable, measures reflection amplitude, calculates a cable length, and determines the cable status based on the measured amplitude and the calculated cable length. A first digital signal processor (DSP) communicates with a first pair of the cable and includes a first echo canceller having a finite impulse response (FIR) filter with taps and a first crosstalk canceller having a FIR filter with taps. A second DSP communicates with a second pair of the cable and includes a second echo canceller having a FIR filter with taps and a second crosstalk canceller having a FIR filter with taps. The cable tester calculates a distance to at least one of echo and crosstalk based on values of the taps of the first echo canceller and the second crosstalk canceller.
|
