Patent ID: 7667830

Claim:
An apparatus to measure optical characteristics of a fiber optic transmission line or other optical medium, comprising: a bipolar pulse generator to generate a bipolar pulse signal waveform; a variable delay module to receive the bipolar pulse signal waveform from the bipolar pulse generator, wherein the variable delay module is variable to delay a bipolar pulse of the bipolar pulse signal waveform by a selected one of different time delay durations, each time delay duration corresponding to a different segment along the transmission line or optical medium to measure optical characteristics from a selected one of the different segments along the transmission line or optical medium; and a mixer to mix the bipolar pulse signal waveform from the variable delay module and an optical pulse and reflected signal waveform from the fiber optic transmission line or other optical medium to form a mixed product waveform, wherein the reflected signal is responsive to the optical pulse being transmitted into the fiber optic transmission line or optical medium.