Visual Media Coding and Transmission

7.1 Introduction

The goal of wireless communication is to allow a user to access required services at any time with no regard to location or mobility. Recent developments in wireless communication, multimedia technology, and microelectronics technology have created a new paradigm in mobile communications. Third/fourth-generation wireless communication technologies provide significantly higher transmission rates and service flexibility, over a wider coverage area, than is possible with second-generation wireless communication systems.

High-compression, error-robust multimedia codecs have been designed to enable the support of a multimedia application over error-prone bandwidth-limited channels. The advances of VLSI and DSP technologies are preparing light-weight, low-cost, portable devices capable of transmitting and viewing multimedia streams. The above technological developments have shifted the service requirements of future wireless communication systems from conventional voice telephony to business-oriented multimedia services.

To successfully meet the challenges set by future audiovisual communication requirements, the International Telecommunication Union Radiocommunication Sector (ITU-R) has elaborated on a framework for global third-generation standards by recognizing a limited number of radio access technologies. These are Universal Mobile Telecommunications System (UMTS), Enhanced Data rates for GSM Evolution (EDGE), and CDMA2000. UMTS is based on Wideband CDMA technology ...