WCDMA is a wideband spread-spectrum 3G mobile telecommunication air interface that utilizes code division multiple access (or CDMA the general multiplexing scheme, not to be confused with CDMA the standard). It provides simultaneous support for a wide range of services with different characteristics on a common 5MHz carrier.
The term WCDMA also refers to one of the International Telecommunications Union’s IMT-2000 standards, a type of 3G cellular network. WCDMA is the technology behind the 3G UMTS standard and is closely allied with the 2G GSM standard. It provides new service capabilities, increased network capacity and reduced cost for voice and data services.
The term ‘WCDMA Evolved’ describes the evolution of WCDMA, addressing both operators’ needs for efficiency and users’ demands for enhanced experience and convenience. The first steps of this evolution are HSDPA and Enhanced Uplink.
Only key features are cited below.
Radio channels are 5MHz wide.
Chip rate of 3.84 Mcps
Supports two basic modes of duplex: frequency division and time division. Current systems use frequency division, one frequency for uplink and one for downlink. For time division, FOMA uses sixteen slots per radio frame, whereas UMTS uses fifteen slots per radio frame.
Employs coherent detection on both the uplink and downlink based on the use of pilot symbols and channels.
Supports inter-cell asynchronous operation.
Variable mission on a 10 ms frame basis.
Adaptive power control based on SIR (Signal-to-Interference Ratio).
Multiuser detection and smart antennas can be used to increase capacity and coverage.
Multiple types of handoff (or handover) between different cells including soft handoff, softer handoff and hard handoff.
CDMA Basics Tutorial
Tutorial and information of the basics about the way direct sequence spread spectrum (DSSS) can be used to provide the CDMA (code division multiple access) technology for mobile, cell or cellular phone systems, or any other system
Information on CDMA technology including comparisons to the two traditional ways of multiple access, Frequency Division Multiple Access (FDMA) and Time Division Multiple Access (TDMA).
Introduction to CDMA
introduction to Code Division Multiple Access (CDMA) communications, covering a Radio Carrier Station (RCS) and a Fixed Subscriber Unit (FSU)
Definition of W-CDMA
W-CDMA (Wideband Code Division Multiple Access), a type of 3G cellular network, is the higher speed transmission protocol used in the Japanese FOMA system and in the UMTS system, an advanced 3G system, designed as a replacement for the ageing 2G GSM networks deployed worldwide
Innovations in WCDMA
Basic concepts of HSPA
HSPA, the undisputed choice for mobile broadband
Services in the Basic concepts of HSPA
Wireless networks for in-building environments
Full service broadband architecture
WCDMA (or W-CDMA) stands for Wideband Code Division Multiple Access. WCDMA is direct spread technology, which means that it will spread its transmissions over a wide, 5MHz carrier. Hence the name W (wideband) CDMA. WCDMA is the leading 3G wireless standard in the world today. It was adopted as a standard by the ITU under the name “IMT-2000 direct spread.” WCDMA is the technology used in the Universal Mobile Telecommunications System (UMTS), and with data rates up to 2Mbits it has the capacity to easily handle bandwidth-intensive applications such as video, data, and image transmission necessary for mobile internet services. Operators such as Vodafone, Singtel, AT&T and TIM have chosen WCDMA/UMTS as their 3G solution.
After slow growth for many years, it appears that 3G/WCDMA/UMTS is finally taking hold — preliminary figures indicate that as 2005 closed, there were 44 million W-CDMA subscribers worldwide, an increase of 164% over the number registered at the end of 2004.
The articles, resources and links
Introduction to Wideband Code Division Multiple Access (WCDMA) (Paperback) , by Lawrence Harte . Paperback- 108 pages (August 2004).
WCDMA (UMTS) Deployment Handbook: Planning and Optimization Aspects , by Christophe Chevalier et al (Editors). Hardcover – 412 pages (September 29, 2006).
WCDMA: GPRS and 3G Wireless Applications: Professional Developer’s Guide, by Christoffer Andersson. Paperback – 352 pages Bk&Cd-Rom edition (April 11, 2001).
UMTS Mobile Communications for the Future, by Flavio Muratore (Editor). Hardcover – 264 pages (January 16, 2001).
UMTS Networks: Architecture, Mobility and Services, by Heikki Kaaranen (Editor), Siamäk Naghian, Lauri Laitinen, Ari Ahtiainen, & Valtteri Niemi. Hardcover – 384 pages 1st edition (August 14, 2001).
The UMTS Network and Radio Access Technology: Air Interface Techniques for Future Mobile Systems, by Jonathan P. Castro. Hardcover – 384 pages 1 edition (April 4, 2001).
Good lecture notes
“WCDMA for UMTS.
Radio Access For Third Generation Mobile Communications.”
Introduction to 3G systems. Radio channel models.
Evolution from GSM to UMTS.
User traffic modeling for future mobile systems.
Introduction to WCDMA.
User traffic modeling for future mobile systems.
You might be interested also on a version of this lecture from the last year course givben by mr. Atte
Länsisalmi from Nokia Reserach Center
WCDMA Physical Layer
WCDMA Radio Interface Protocols
WCDMA Radio Network Planning
WCDMA Packet Access
WCDMA Radio Resource Management
WCDMA Physical Layer Performance