Detection of signals transmitted by frequency-shift keying modulation techniques
US6724836B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 2000 |
| Grant date | Apr 20, 2004 |
| Priority date | — |
| Expiry date | Jul 30, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/144
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An apparatus and method of detecting signals transmitted via frequency-shift keying techniques. An observation window encompassing a frequency band is defined and searched for received tones, the frequency spacing between received tones is calculated and compared to known FSK modulation techniques to determine whether at least part of a transmission is potentially present. The transmission may be an automatic link establishment signal. A histogram can store data on received tones. The observation window can be shifted to center a potential FSK transmission for parallel modem processing that will attempt to demodulate and decode it.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.