Radio receiver incorporating a data operated squelch system
US4554665A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 7, 1983 |
| Grant date | Nov 19, 1985 |
| Priority date | — |
| Expiry date | Feb 7, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/20
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A data processing system of the kind in which there is a transmission of a code format having a pattern that provides a plurality of reversals 10101100 etc. from which it is desirable to be able to differentiate between valid data and invalid data. Invalid data means the absence of data, data corrupted by noise or data alien to the system. The system is characterized by means arranged to provide the times between n zero crossings as given by the expression: ##EQU1## where I is the integer part of x, n is an integer representing the number of zero crossings and t.sub.i is the duration of the ith interval between zero crossings measured on a bit base of unity thereby to permit the use of said number (R) when compared with a predetermined tolerance range to provide an indication of the quality of said transmission.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.