Low-latency audio interface for packet telephony
US6556560B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 4, 1997 |
| Grant date | Apr 29, 2003 |
| Priority date | — |
| Expiry date | Dec 4, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M7/006
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
In a method for reducing latency in packet telephony caused by buffering at the conversion stage between analog audio signals and digital audio data, analog audio is sampled at a rate far greater than necessary for telephony. The increased sampling rate allows the audio data to pass much more rapidly through the data conversion buffer. After passing through the buffer, the data is downsampled to a rate normally used for telephony. To handle audio data for speaker output, the data is upsampled to a rate far in excess of the rate necessary for processing telephony-grade voice signals. The increased sampling rate allows the audio data to pass much more rapidly through the data conversion buffer. After passing through the buffer, the data is converted into an analog audio signal for sending to the speaker. In this way, latency due to the buffering that accompanies the process of converting audio signals to digital data, or vice versa, is minimized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.