Method and RFID reader for detecting a delimiter pattern in a signal stream
US8014474B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 5, 2006 |
| Grant date | Sep 6, 2011 |
| Priority date | — |
| Expiry date | Sep 9, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L7/042
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method for detecting a delimiter pattern (SOF) in a signal stream containing a carrier or subcarrier modulated by the delimiter pattern comprises: specifying an expected delimiter occurrence time (t1) of an occurrence of the delimiter pattern and a tolerance zone (tz) within which the expected delimiter occurrence time (t1) may jitter; approximating, within the tolerance zone (tz), a zero of a cross correlation function (CCF) of the data stream with the delimiter pattern, or detecting the phase (φ) of the carrier or subcarrier in respect to an arbitrarily defined reference position within the tolerance zone (tz), e.g. in respect to the expected delimiter occurrence time (t1); calculating a first maximum of the cross correlation function (CCF) within the tolerance zone (tz) by use of the approximated zero or phase (φ); calculating all other maxima of the cross correlation function (CCF) within the tolerance zone (tz); detecting the highest maximum among the calculated maxima, which highest maximum is representative for the moment in time of occurrence of the delimiter pattern.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.