Null-pilot symbol assisted fast automatic frequency control (AFC) system for coherent demodulation of continuous phase modulation (CPM) signals and method for implementing same
US6625237B2 · kind B2 · utility
3Cited by
3References
8Claims
0Family size
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Key dates
| Filing date | Jul 31, 2001 |
| Grant date | Sep 23, 2003 |
| Priority date | — |
| Expiry date | Feb 27, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2027/0087
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A null-pilot symbol assisted fast automatic frequency control (AFC) system for coherent demodulation of carrier phase modulation (CPM) includes (209) a pilot clock driven phase differentiator (252,253,255) for operating once every pilot clock cycle to determine the difference between the phase at a current pilot symbol location and the phase at a previous pilot symbol location. A frequency offset selector (256) is then used for choosing the most likely frequency offset from amongst a set of all frequency offsets that give rise to the same phase difference.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.