Method and apparatus for sensing noise signals in a wireline communications environment
View Patent ↗The present invention relates to methods and apparatuses for sensing noise sources in a wireline communications environment such as a customer premises environment in a DSL system. In embodiments, the invention includes an additional sensor that is connected to power mains in a DSL customer premises environment either to characterize, at their source, noises coupling into the DSL lines, and/or to mitigate their impact into the DSL lines. One objective is associated with diagnostics that help to better characterize the noise signals themselves and derive correlation of signals sensed from the power mains and their possible projection onto the DSL line. Another objective makes use of these power line sensor signals to mitigate or to eliminate power line noises that make their way onto the DSL line. Example embodiments further include and exploit signals from additional secondary sensors such as secondary common mode, differential mode and phantom mode sensors.
1. A method of wireline communications by a device in a customer premises environment, comprising:
receiving data signals by a primary sensor of the wireline communications;
receiving power line signals by a power line sensor of the wireline communications, wherein the power line signals correspond to noise affecting the data signals and originating from power mains in the customer premises environment; and
using the received power line signals to characterize the noise affecting the data signals.
2. The method of claim 1 , further comprising:
determining an associated impact of the characterized noise on the wireline communications.
3. The method of claim 2 , wherein characterizing the noise is performed by a primary sensor, a power line sensor, and a secondary common mode sensor.
4. The method of claim 2 , wherein characterizing the noise further comprises:
determining a coupling between at least two of a primary sensor, a power line sensor, and a secondary common mode sensor.
5. The method of claim 2 , wherein characterizing the noise further comprises:
estimating a noise source power on one or more sensors and noise correlation across the one or more sensors.
6. The method of claim 5 , further comprising:
determining a number and relative location of noise sources based at least in part on characterizing the noise.
7. The method of claim 1 , further comprising:
cancelling the noise affecting the data signals based at least in part on the power line signals.
8. The method of claim 7 , wherein cancelling the noise affecting the data signals complements another cancellation process that is performed using a secondary sensor.
9. The method of claim 8 , further comprising:
conditionally selecting output from a canceller.
10. The method of claim 7 , wherein cancelling the noise affecting the data signals further comprises using a combination of outputs as a linearly weighted sum.
11. The method of claim 7 , further comprising:
performing adaptive linear filtering on the data signals and the power line signals.
12. The method of claim 7 , wherein cancelling the noise affecting the data signals is on a per tone basis in a frequency domain.
13. The method of claim 1 , further comprising:
collecting information regarding the received data signals and the received power line signals; and
classifying the noise based at least in part on the information.
14. The method of claim 13 , further comprising:
collecting the information regarding the noise while the wireline communications are transmitted and received.