Pilot signal detection system using band reject filter
US5986499A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 21, 1998 |
| Grant date | Nov 16, 1999 |
| Priority date | — |
| Expiry date | Dec 21, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F1/3229
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A pilot signal detection system uses a band reject filter to reject the frequency band of at least one carrier signal to improve pilot signal detection. For example, in a feed forward distortion reduction system, the carrier signal(s) is on a main signal path along with a pilot signal which is injected into the main signal path at a frequency adjacent to the frequency band of the carrier signal(s). The carrier signal(s) and the pilot signal are amplified on the main signal path, resulting in distortion on the main signal path. To reduce the distortion from the main signal path, the feed forward distortion reduction system detects and reduces the pilot signal. To improve detection of the pilot signal, the pilot signal detection system provides a signal representative of the carrier signal(s) and the pilot signal with distortion from the main signal path onto a pilot detection path. A band reject filter on the pilot detection path rejects the frequency band of the carrier signal(s) while allowing the frequency of the pilot signal to pass through to pilot detect circuitry. Without the presence of the carrier signal(s), the pilot detect circuitry can more accurately detect the pilot si…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.