ANALOG SCAN DATA SIGNAL PROCESSOR EMPLOYING A TIME-DOMAIN SUBSTRATE NOISE FILTER FOR NON-LINEARLY PROCESSING ANALOG SCAN DATA SIGNALS AND REDUCING SUBSTRATE NOISE SIGNAL LEVELS THEREIN PRIOR TO FIRST DERIVATIVE SIGNAL GENERATION AND PROCESSING OPERATIONS CARRIED OUT WITHIN SAID ANALOG SCAN DATA SIGNAL PROCESSOR
US6616040B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 9, 2000 |
| Grant date | Sep 9, 2003 |
| Priority date | — |
| Expiry date | Feb 9, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An analog scan data signal processor is disclosed, in which a time-domain non-linear substrate noise filter is provided before a first derivative signal generation stage so as to produce, as output, a substantially fixed zero-reference signal level whenever a signal level indicative of a bar code substrate is detected, and the signal level analog scan data signal, whenever a signal level indicative of a bar code element is detected. By virtue of the present invention, it is now possible to reduce the level of substrate noise signals within input analog scan data signals, prior to deriving first derivative signals for subsequent signal processing. Consequently, the accuracy of binary signal level detection within such analog scan data signal processors can be significantly improved, thereby improving the performance of bar code symbol reading systems within which such analog scan data signal processors are employed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.