Full duplex speakerphone system
US6009165A · kind A · utility
7Cited by
11References
34Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Aug 22, 1997 |
| Grant date | Dec 28, 1999 |
| Priority date | — |
| Expiry date | Aug 22, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M9/08
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The improved full duplex speakerphone system replaces two A/D converters normally required in conventional speakerphone systems with a single A/D converter. This single A/D converter is a higher speed A/D converter which is multiplexed at its input. By alternately connecting the A/D converter between a microphone input circuit and a telephone line input circuit, the single higher speed A/D converter can be used to digitize both input signals. Because the A/D converter samples the data at a much higher rate and uses a digital filter to greatly reduce the impact of aliasing, very simple, low cost external filters may be used.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.