Patent ID: 9548793
Date: 2017-01-17
CPC Classifications: H04B,H04L

Claim:
1. A method, comprising: projecting, by a system comprising a processor and a frequency domain reflectometer coupled to the processor, a signal having a predetermined frequency content into a communications link and detecting a reflected signal developed in response to the projected signal and received by the frequency domain reflectometer; processing, by the system, the reflected signal received by the frequency domain reflectometer; generating, by the system, a transformed distribution of the reflected signal, the transformed distribution comprising a reflection coefficient distribution represented by a magnitude of reflection coefficient values as a function of physical distance along the communications link; subsequently selecting, by the system, a first peak reflection coefficient value in the reflection coefficient distribution, wherein a magnitude of the first peak reflection coefficient value is a highest magnitude when compared to other peak reflection coefficient values in the reflection coefficient distribution; generating, by the system, a first model distribution using a first model function, the first model distribution representing magnitudes of reflection coefficient values as a function of physical distance along the communications link; performing, by the system, a first local fit to the selected first peak reflection coefficient value using the first model function, wherein the first model function utilizes the magnitude of the selected first peak reflection coefficient value and determines by regression a first curve fitting parameter value until the first model function satisfies a first predetermined criterion; forming, by the system, a first residue distribution of reflection coefficient values as a function of physical distance along the communications link, based upon a first difference between the reflection coefficient distribution and the first model distribution; selecting, by the system, a second peak reflection coefficient value in the first residue distribution, wherein a magnitude of the second peak reflection coefficient value is a highest magnitude when compared to other peak reflection coefficient values in the first residue distribution; performing, by the system, a second local fit to the selected second peak reflection coefficient value using a second model function that generates a second model distribution, wherein the second model function utilizes the magnitude of the selected second peak reflection coefficient value and determines by regression a second curve fitting parameter value until the second model function satisfies a second predetermined criterion; forming, by the system, a second residue distribution based upon a second difference between the first residue distribution and the second model distribution; identifying, by the system, a first location of a first discontinuity, based upon the first residue distribution; identifying, by the system, a second location of a second discontinuity in the communications link, based upon the second residue distribution; correcting, by the system, the first location, according to wherein L outputting, by the system, for the first discontinuity, a first discontinuity location, a first discontinuity strength, and a first discontinuity type, and outputting, by the system, for the second discontinuity, a second discontinuity location, a second discontinuity strength, and a second discontinuity type, wherein the discontinuity location corresponds to the corrected location, wherein the discontinuity strength corresponds to a peak magnitude in the reflection coefficient distribution, the discontinuity strength being positive or negative, wherein the discontinuity type corresponds to an open termination for a positive discontinuity strength and a shorted termination for a negative discontinuity strength, wherein the first curve fitting parameter value corresponds to the physical distance along the communications link, wherein processing the reflected signal comprises performing a discrete Fourier transform on the reflected signal to generate the reflection coefficient distribution, and wherein performing the first local fit to the selected first peak reflection coefficient value comprises locally fitting a Gaussian distribution having the magnitude of the selected first peak reflection coefficient value by varying the first curve fitting parameter value.