| 摘要 |
<p>A subscriber loop interface circuit, with a method and apparatus for measuring loop impedance. Measurement of loop impedance including charging and discharging a capacitor (34) using current derived from loop current and loop voltage. The discharge time interval of the capacitor (34) may provide information on loop impedance. A look-up table (50) in a subscriber loop interface circuit may include previously calculated impedance values corresponding to discharge time. <IMAGE></p> |
