Method and apparatus for combatting ingress and multipath in a CATV return channel
US5881363A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 1996 |
| Grant date | Mar 9, 1999 |
| Priority date | — |
| Expiry date | Apr 29, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2025/03808
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a CATV return channel between a transmitter and a headend receiver, the transmitter is provided with a precoder having programmable but fixed coefficients. The receiver is provided with an ingress rejection filter (IRF) having programmable but fixed coefficients. A non-precoded training sequence is sent from the transmitter to the receiver during a training interval. A multipath and an ingress in the CATV return channel are estimated at the receiver based upon the training sequence sent by the transmitter and received by the receiver. The precoder coefficients and the IRF coefficients are calculated and the precoder and the ingress rejection filter are programmed with the calculated coefficients, respectively. The precoder and the ingress rejection filter use the respective calculated coefficients during a data transmission interval to simultaneously compensate for undesirable effects of multipath and ingress noise in the CATV return channel during data transmission from the transmitter to the headend.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.