Voice recording and playback mode using the G.726 half-rate within the personal handy phone system
US6256354A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 20, 1998 |
| Grant date | Jul 3, 2001 |
| Priority date | — |
| Expiry date | Feb 20, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M1/6505
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Voice recording and playback mode using the G.726 half-rate within the personal handy phone system (PHS). When a portable station within the PHS operates as a voice recorder (e.g., functioning as an answering machine), a cost effective system in accordance with the present invention is adapted to compress and store received voice/sound signals in order to increase the usage of limited memory resources provided within the portable station. The present invention also enables previously compressed and stored voice/sound signals to be decompressed and played back in various portable station playback modes. Specifically, the portable station receives a voice/sound signal in a full rate (e.g., 32 kilobits-per-second) 4-bit adaptive differential pulse code modulation (ADPCM) data format in compliance with the International Telecommunication Union (ITU) recommendation G.726. The present invention compresses this received voice/sound signal to a half rate (16 kilobit-per-second) 2-bit ADPCM data format in compliance with the ITU recommendation G.726 in order to increase the usage of the limited memory resources provided within the portable station. During a playback mode of the portable sta…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.