Wired and cordless telephone systems with extended frequency range

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 received compressed digital signal, the decompression block reconstructs a digital audio signal at the high data rate. The D/A converter generates a reconstructed analog audio signal in response to the reconstructed digital audio signal.