Radio LAN station with improved frame delimiter detection in a spread spectrum environment
US5151920A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1991 |
| Grant date | Sep 29, 1992 |
| Priority date | — |
| Expiry date | Sep 10, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W88/02
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A radio LAN station is provided for receiving information frames including start and end delimiters and user data therebetween. The start and end delimiters include both data symbols and special non-data symbols. The data symbols and non-data symbols being transmitted to the radio LAN station are sent thereto via a spread spectrum signal. The data symbols and the non-data symbols are spread via first and second spreading codes, respectively. The receiving radio LAN station includes first and second correlators which respectively correlate the received spread spectrum signal against the first spreading code to retrieve the data symbols and against the second spreading code to retrieve the non-data symbols. Rectangular representations of the received data and non-data symbols are thus produced and are converted to polar form via appropriate rectangular to polar converters. The polar representations of the data and non-data symbols respectively exhibit a vector length Z and a vector length Z'. The receiving LAN station includes circuitry for determining that a symbol is a data symbol if Z - Z' is greater than or equal to a constant A, or that a symbol is a non-data symbol if Z - Z1 is…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.