tailieunhanh - Hệ thống truyền thông di động WCDMA P6

The Introduction of International Mobile Telecommunications-2000 (IMT-2000) has enabled high-speed data transmission, laying the groundwork for full-scale multimedia communications in mobile environments. Taking into account the characteristics and limitations of radio access, multimedia processing suitable for mobile communication is required. In this chapter, signal processing, which is a basic technology for implementing multimedia communication, is first discussed. It contains descriptions on the technology, characteristics and trends of the Moving Picture Experts Group (MPEG-4) image coding method. | W-CDMA Mobile Communications System. Edited by Keiji Tachikawa Copyright 2002 John Wiley Sons Ltd. ISBN 0-470-84761-1 6 Multimedia Processing Scheme Minoru Etoh Hiroyuki Yamaguchi Tomoyuki Ohya Toshiro Kawahara Hiroshi Uehara Teruhiro Kubota Masayuki Tsuda Seishi Tsukada Wataru Takita Kimihiko Sekino and Nobuyuki Miura Overview The Introduction of International Mobile Telecommunications-2000 IMT-2000 has enabled high-speed data transmission laying the groundwork for full-scale multimedia communications in mobile environments. Taking into account the characteristics and limitations of radio access multimedia processing suitable for mobile communication is required. In this chapter signal processing which is a basic technology for implementing multimedia communication is first discussed. It contains descriptions on the technology characteristics and trends of the Moving Picture Experts Group MPEG-4 image coding method the Adaptive MultiRate AMR speech coding and 3G-324M. MPEG-4 is regarded as a key technology for IMT-2000 developed for use in mobile communication and standardized on the basis of various existing coding methods. AMR achieves excellent quality designed for use under various conditions such as indoors or on the move. 3G-324M is adopted by 3rd Generation Partnership Project 3GPP as a terminal system technology for implementing audiovisual services. A functional overview of mobile Internet Service Provider ISP services using the IMT-2000 network is also provided together with some other important issues that must be taken into account when providing such services including the information distribution method copyright protection scheme and trends in the content markup language. The standardization direction in Wireless Application Protocol WAP Forum - a body responsible for the development of an open globally standardized specification for accessing the Internet from wireless networks and the technical and standardization trends of a common platform .