Digital envelope detection circuit
US4622481A · kind A · utility
8Cited by
6References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Aug 21, 1985 |
| Grant date | Nov 11, 1986 |
| Priority date | — |
| Expiry date | Aug 21, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03J9/06
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
This circuit provides a digital output indicating the presence or absence of the infrared (IR) carrier signal. The incoming IR signal is sampled by a clock at a frequency which is about 4 times the carrier frequency. The high and low samples are tabulated in two counters in a race. When 8 high or 16 low samples are counted, the envelope status flip flop is set or reset, respectively, and both counters are reset. The output of the envelope status flip flop represents the envelope of the IR carrier signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.