In-band and out-of-band signal detection for automatic gain calibration systems
US6721547B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 2001 |
| Grant date | Apr 13, 2004 |
| Priority date | — |
| Expiry date | Nov 21, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/1036
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An embodiment of the present invention provides an automatic gain control system for a wireless receiver that quickly differentiates desired in-band signals from high power out-of-band signals that overlap into the target band. The system measures power before and after passing a received signal through a pair of finite impulse response filters that largely restrict the signal's power to that which is in-band. By comparing the in-band energy of the received signal after filtering to the total signal energy prior to filtering, it is possible to determine whether a new in-band signal has arrived. The presence of this new in-band signal is then verified by a multi-threshold comparison of the normalized self-correlation to verify the presence of a new, desired in-band signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.