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发表于 2008-9-28 20:12:22
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RFCD 202: Introduction to W-CDMA
Welcome to module RFCD 202 – an introduction to the W-CDMA system. We strongly recommend that you study both the RFCD 101 (CDMA basics)
and RFTD 101 (GSM basics) before this module – many of the concepts discussed here are introduced in the two modules mentioned.
This module examines the core concepts of one operating mode of the IMT-2000 world wide system: 3GPP WCDMA. This system is based on the
WCDMA system developed in Japan and Europe. While this standard is a part of the harmonized worldwide standard, it will continue to be developed
by the 3GPP standards body that originally developed it. This paper covers the standard as found in the Release 99 version completed in December
1999. A number of features of the 3GPP system have been omitted in the Release 99 standard in order to meet the time schedule. These omitted
features, as well as new services, will be added in a second release of the standard to be completed at the end of 2000.
The physical aspects of the air interface are examined as well as enough of the upper protocol layers required to gain a general understanding of the
system’s operating principles. This paper assumes that the reader has a basic understanding of the principles of direct sequence, spread spectrum
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