Title :
An I-phone system design and implementation with a portable speech coding coprocessor
Author :
Chen, Ruei-Xi ; Chen, Liang-Gee ; Chen, Mei-Juan ; Tsai, Tsung-Han
Author_Institution :
Dept. of Electr. Eng., Nat. Taiwan Univ., Taipei, Taiwan
fDate :
11/1/1997 12:00:00 AM
Abstract :
This paper presents a high quality, low bit rate, and portable Internet-phone system. The system consists of a mixed implementation of software and hardware. The hardware includes a portable box that can be plugged into the conventional parallel port. Three major parts are considered in this box: the speech compression unit, the host interface, and the speakerphone module. A low-cost non-delicate speech coprocessor is embedded to process the heavy job of speech coding, a CPLD device is employed to control the host access timing, a 16-bit PCM codec and an audio amplifier with acoustic echo cancellation features are introduced to optimize the speakerphone module. The experimental coding rate is 8.5 kbps. At such a rate, the popular modems can conform to offer full-duplex speech in real time. Modern applications of this system include digital simultaneous voice data (DSVD) transmission, such as net-game´s talking and video-conferencing
Keywords :
Internet; coprocessors; data communication; digital signal processing chips; network interfaces; programmable logic devices; pulse code modulation; speech codecs; speech coding; speech processing; teleconferencing; telephone sets; voice communication; 16 bit; 8.5 kbit/s; CPLD device; DSP coprocessor; I-phone system design; Internet-phone system; PCM codec; acoustic echo cancellation; audio amplifier; coding rate; digital simultaneous voice data transmission; full-duplex speech; host access timing; host interface; modems; network-game talking; parallel port; portable speech coding coprocessor; software; speakerphone module; speech coding; speech compression unit; video-conferencing; Acoustic devices; Bit rate; Coprocessors; Hardware; Internet; Phase change materials; Speech codecs; Speech coding; Speech processing; Timing;
Journal_Title :
Consumer Electronics, IEEE Transactions on
