Method of automated demodulation and classification of phase-shift-keying signals using hysteretic differential zero-crossing time samples
US8149956B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 23, 2007 |
| Grant date | Apr 3, 2012 |
| Priority date | — |
| Expiry date | Dec 6, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2337
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An automatic zero-crossing signal demodulation and classification device for rapidly identifying an unknown modulation in a signal identifies an unknown modulation in a signal, demodulates differential phase shift keying signals and automatically recognizes certain phase shift keying signals. This is accomplished by eliminating the unknown term fc in differential phase estimation, introducing a symbol rate tracking mechanism, applying hysteresis nonlinearity to eliminate the phase shaping effect and using a weighted average to estimate the phase difference. Better estimates are accomplished by using the hysteretic nonlinear function to detect the zero-crossing points in eliminating the false detecting of the zero-crossing points caused by the additive noise, and calculating differential phase without directly using the center frequency to simplify the estimation process. The present invention also encompasses an automated zero-crossing signal surveillance demodulation and classification device for rapidly identifying an unknown modulation in a signal and a method for automatic zero-crossing demodulation and classification of an unknown modulation signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.