Wired and cordless telephone systems with extended frequency range
US6556965B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 1999 |
| Grant date | Apr 29, 2003 |
| Priority date | — |
| Expiry date | Mar 24, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M1/737
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A telephone that communicates high-quality audio signals and a method for communicating an audio signal with an extended frequency range over a telephone network. The cordless telephone has a handset unit with a sampler circuit, a compression circuit, decompression circuit, as well as analog-to-digital (A/D) and digital-to-analog (D/A) converters, which handset is coupled by an infrared (IR) wireless link to a base unit connected to the Public Switched Telephone Network (PSTN). In one embodiment, the telephone includes a sampler, a compression block, a telephone port, a decompression block, and a digital-to-analog (D/A) converter. The sampler receives a analog audio signal and digitizes the signal into a high-quality (705.6 kbps) digital audio signal. The compression block then encodes the digital audio signal into a compressed digital signal at a lower bit rate (such as 150 kbps or 56 kbps) with a compression algorithm such as MP3. The compressed digital signal is communicated through the telephone port to a telephone network. An incoming compressed digital signal is received from the telephone network by the telephone port and provided to the decompression block. From the receive…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.