外文文献及翻译：3g技术

外文文献及翻译：3g技术内容摘要：

at once. WCDMA is fully pliant with IMT2020 and is the air interface technology for standards in the 2GHz bandwidth (the IMT2020 core band), known as UMTS (Universal Mobile Telemunication System) in Europe and ARIB (Association of Radio Industry Businesses) in Japan. Ericsson has been at the forefront of WCDMA development. The pany delivered an experimental WCDMA system to NTT DoCoMo in Japan back in 1998. Ericsson has also set up WCDMA test systems around the world. At 2020, Ericsson announced its first family of WCDMA base stations. EDGE Enhanced Data Rates for Global Evolution (EDGE) enables GSM and TDMA operators to offer 3G services using existing work frequencies. By making changes and additions to standardization of evolutionary phases of the air interface and the backbone works, as well as the migration to ALLIP and multimedia works. cdma2020 cdma2020 is a decidedly efficient 3G standard for the delivery of high bandwidth data and high capacity voice services. The evolution of the cdma2020 standard will enable mobile systems to offer data throughputs of 2 Mbit/sec and beyond. The higher bandwidth that cdma2020 provides will deliver the full potential of 3G. For example, cdma2020 also allows simultaneous access to several voice, video and data services at once. cdma2020 is fully pliant with IMT2020 requirements for 3G. cdma2020 will be implemented in the existing frequency bands of CMDA and TDMA at 800 and 1900 MHz, as well as in new spectrum at 2GHz in Japan. Ericsson is a leader in cdma2020 development, and a key driver in the standardization of evolutionary phases of the air interface and the backbone works, as well as the migration to ALLIP and multimedia works. Bluetooth Bluetooth is an open standard for twoway, shortwave radio munications between different devices. It marks the end of cables and cords between mobile phones, palmtops, portable PCs and printers, for example. Furthermore, Bluetooth enables information between such devices to be synchronized. Diary information held on a PDA can be updated automatically when within range of a Bluetoothenabled PC. Bluetooth is also going to be important for machinetomachine munications one of the largest growth areas in telemunications. Bluetooth is a key development for terminals and other devices using mobile works. It is available now for 2G works and as 3G systems, will play an increasingly important supporting role in the future of mobile munications. Ericsson has already announced Bluetooth devices, including the T36 Bluetooth phone and a Bluetooth headset. Bluetooth was originally developed by Ericsson, but is now under the auspices of the Bluetooth Special Interest Group. It has widespread support among tele equipment vendors, puter and chip manufacturers. Symbian Symbian is an independent joint venture supported by panies including Ericsson, Nokia, Motorola and Psion. Symbian aims to promote a mass market for mobile information devices in two ways:  First, through the development of core softwar。