Methods and devices for transmission line analysis

摘要

Improved diagnostics of transmission line (100) noise are enabled by adapting DSL equipment (110, 120) to make measurements of quiet line noise also in the transmit bands, so that noise can be measured at both ends for the same frequency or frequency bands. An estimate of the point where noise enters the line, as well as an estimate of the noise power at that point can be made from the relationship between the so measured noise levels at both ends of the line.

主权项

1. A method for estimating a position where noise enters a telecommunications transmission line said line having first digital subscriber line (DSL) communications equipment connected to a first end of the line and second DSL communications equipment connected to a second, opposite end of the line the method comprising the following steps:
receiving, via the line, a first result of a measurement of a noise level at the first end of the transmission line made by the first DSL equipment; receiving a second result of a measurement of a noise level at the second end of the transmission line made by the second DSL equipment; and generating an estimate of the position where the noise enters the transmission line based on the relationship between the first and the second noise level measurement results where the first and second noise level measurements are made at the same frequency or frequency band and said frequency or frequency band falls within a transmit band of at least one of said first and second DSL equipment.