摘要:
The present invention presents a method of identifying faults in a DSL line using upstream and downstream attenuation measurements, which can be obtained directly from the DSLAM or CPE, thus requiring no specialist test equipment nor disrupting service. A downstream over upstream attenuation ratio is calculated for a line, with calculations repeated over a population of lines. The distribution of ratios, as well as upper and lower thresholds, is determined based on the population. A line is identified as being potentially faulty if it has an attenuation ratio above the upper threshold or below the lower threshold. Specifically, an attenuation ratio below the lower threshold is identified as having a high resistance joint fault (caused by an imperfect connection or corrosion at a joint in at least one of the pairs of a line), and a ratio above the upper threshold as a shunt (caused by degradation of the insulation between the pairs of a line, and often coupled with water ingress).
摘要:
The invention presents a method of identifying faults on a DSL line, typically intermittent faults arising from unstable joints in the DSL line. The method collects errored seconds data at the DSLAM and at the customer's premises equipment (CPE, typically a home hub or router). The error data collected at the DSLAM are termed near-end errors, and the error data collected at the CPE are termed far-end errors. The near-end and far-end data is then analyzed by applying regression analysis to determine if there is a correlation or match between the two sets of data. Matching data patterns are indicative of unstable or bad joints in the DSL line, and are typically intermittent and located near the customer's premises.