W-CDMA

W-CDMA (Wideband Code Division Multiple Access) is a type of 3G cellular network.

W-CDMA is the technology behind UMTS (a.k.a. 3GSM) and is allied with the 2G GSM standard.

More technically, W-CDMA 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).

Brief History

W-CDMA was developed by NTT DoCoMo as the air interface for their 3G network FOMA.

Later NTT Docomo submitted the specification to ITU as a candidate for the international 3G standard known as IMT-2000.

The ITU eventually accepted W-CDMA as part of the IMT-2000 family of 3G standards.

Later, W-CDMA was selected as the air interface for UMTS, the 3G successor to GSM.

Key Features

• Supports two basic modes: FDD and TDD modes

• Employs coherent detection on uplink and downlink based on the use of pilot symbols

• Inter-cell asynchronous operation

• Variable rate transmission: on a 10 ms frame basis

• Multicode transmission

• Adaptive power control based on SIR

• Multiuser detection and smart antennas can be used to increase capacity and coverage

Misconceptions

Despite the similarity in name, W-CDMA has very little to do with CDMA. How little depends on the point of the viewer.

In the mobile phone world, the term CDMA can refer to either the Code Division Multiple Access spread spectrum multiplexing technique, or the CDMA family of standards developed by Qualcomm, including cdmaOne (or IS-95) and CDMA2000 (or IS-2000).

The CDMA multiplexing technique existed long before Qualcomm used it for its IS-95 protocol.

However, this protocol is now widely referred to as "CDMA" for its principal characteristic of using the CDMA multiplexing scheme to share multiple connections divided by different codes (PN Sequences) over the same spectrum, as opposed to other spectrum division schemes (e.g. GSM's TDMA).

W-CDMA also uses the CDMA multiplexing technique, and has many similarities to the Qualcomm standards.

However W-CDMA is more than a multiplexing standard.

W-CDMA is a complete set of specifications, a detailed protocol that defines how a mobile phone communicates with the tower, how signals are modulated, how datagrams are structured, etc.

In summary:

• The term CDMA in the mobile world typically refers to the CDMA family of standards developed by Qualcomm.

They are protocols, sets of defined specifications of mobile communications

• CDMA (the multiplexing technique) is used as the principle of the W-CDMA air interface protocol, as well as Qualcomm's CDMA protocols

• W-CDMA strictly refers to a mobile phone protocol with detailed specifications, as defined in IMT-2000

• The W-CDMA protocol was developed independently of the CDMA protocol developed by Qualcomm

• The CDMA family of standards (including cdmaOne and CDMA2000) are not compatible with the W-CDMA family of standards

Real-World Implementations

The world's first commercial W-CDMA service, FOMA, was launched by NTT DoCoMo in Japan in 2001.

FOMA is not compatible with UMTS.

But the efforts for migrating the FOMA specifications to UMTS are indicated by Japan.

J-Phone Japan (now Vodafone) soon followed by launching their own W-CDMA based service, originally branded "Vodafone Global Standard" and claiming UMTS compatibility.

The name of the service was changed to "Vodafone 3G" in December 2004.

Beginning in 2003, Hutchison Whampoa gradually launched their upstart UMTS networks (simply called 3) worldwide.

Most Western European GSM providers plan to offer UMTS sometime in the future, though few have committed to an actual timeline.

Some of them have begun launching UMTS networks at the end of 2003.

Vodafone launched several UMTS networks in Europe in February 2004.

Vodafone also has plans to launch UMTS networks in other countries, including Australia and New Zealand.

Vodafone New Zealand have been upgrading their existing base stations for UMTS and have applied to various City Councils for permission to build new 3G base stations.

Vodafone New Zealand plans to launch the UMTS service by the end of 2005.

AT&T Wireless (now a part of Cingular Wireless) has deployed UMTS in several cities.

Though advancements in its network deployment have been delayed due to the merger with Cingular, Cingular has now announced plans to deploy W-CDMA along with HSDPA in 2005.

TeliaSonera opened W-CDMA service in Finland October 13th 2004 with speeds up to 384 kbit/s.

Availability only in main cities.

Pricing is approx. 2€/MB.

SK Telecom and KTF, two largest mobile phone service providers in South Korea, have each started offering W-CDMA service in December 2003.

Due to poor coverage and lack of choice in handhelds, the W-CDMA service has barely made a dent in the Korean market.

In Norway, Telenor introduced W-CDMA in major cities by the end of 2004, while their competitor, NetCom, followed suit a few months later.

Both operators have full national coverage on EDGE.

Maxis Communications and Celcom, two mobile phone service providers in Malaysia, started offering W-CDMA services in 2005.

Technology

W-CDMA may use unpaired or paired spectrum, though the current implementations of W-CDMA (i.e. FOMA and UMTS) all use a pair of 5MHz spectrum, one for uplink and one for downlink.

See Spread spectrum for more information.

FOMA uses 16 slots per radio frame, whereas UMTS uses 15 slots per radio frame.

W-CDMA (Wideband Code Division Multiple Access) is a type of 3G cellular network. W-CDMA is the technology behind UMTS (a.k.a. 3GSM) and is allied with the 2G GSM standard. More technically, W-CDMA 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). Brief History W-CDMA was developed by NTT DoCoMo as the air interface for their 3G network FOMA. Later NTT Docomo submitted the specification to ITU as a candidate for the international 3G standard known as IMT-2000. The ITU eventually accepted W-CDMA as part of the IMT-2000 family of 3G standards. Later, W-CDMA was selected as the air interface for UMTS, the 3G successor to GSM. Key Features • Supports two basic modes: FDD and TDD modes • Employs coherent detection on uplink and downlink based on the use of pilot symbols • Inter-cell asynchronous operation • Variable rate transmission: on a 10 ms frame basis • Multicode transmission • Adaptive power control based on SIR • Multiuser detection and smart antennas can be used to increase capacity and coverage Misconceptions Despite the similarity in name, W-CDMA has very little to do with CDMA. How little depends on the point of the viewer. In the mobile phone world, the term CDMA can refer to either the Code Division Multiple Access spread spectrum multiplexing technique, or the CDMA family of standards developed by Qualcomm, including cdmaOne (or IS-95) and CDMA2000 (or IS-2000). The CDMA multiplexing technique existed long before Qualcomm used it for its IS-95 protocol. However, this protocol is now widely referred to as "CDMA" for its principal characteristic of using the CDMA multiplexing scheme to share multiple connections divided by different codes (PN Sequences) over the same spectrum, as opposed to other spectrum division schemes (e.g. GSM's TDMA). W-CDMA also uses the CDMA multiplexing technique, and has many similarities to the Qualcomm standards. However W-CDMA is more than a multiplexing standard. W-CDMA is a complete set of specifications, a detailed protocol that defines how a mobile phone communicates with the tower, how signals are modulated, how datagrams are structured, etc. In summary: • The term CDMA in the mobile world typically refers to the CDMA family of standards developed by Qualcomm. They are protocols, sets of defined specifications of mobile communications • CDMA (the multiplexing technique) is used as the principle of the W-CDMA air interface protocol, as well as Qualcomm's CDMA protocols • W-CDMA strictly refers to a mobile phone protocol with detailed specifications, as defined in IMT-2000 • The W-CDMA protocol was developed independently of the CDMA protocol developed by Qualcomm • The CDMA family of standards (including cdmaOne and CDMA2000) are not compatible with the W-CDMA family of standards Real-World Implementations The world's first commercial W-CDMA service, FOMA, was launched by NTT DoCoMo in Japan in 2001. FOMA is not compatible with UMTS. But the efforts for migrating the FOMA specifications to UMTS are indicated by Japan. J-Phone Japan (now Vodafone) soon followed by launching their own W-CDMA based service, originally branded "Vodafone Global Standard" and claiming UMTS compatibility. The name of the service was changed to "Vodafone 3G" in December 2004. Beginning in 2003, Hutchison Whampoa gradually launched their upstart UMTS networks (simply called 3) worldwide. Most Western European GSM providers plan to offer UMTS sometime in the future, though few have committed to an actual timeline. Some of them have begun launching UMTS networks at the end of 2003. Vodafone launched several UMTS networks in Europe in February 2004. Vodafone also has plans to launch UMTS networks in other countries, including Australia and New Zealand. Vodafone New Zealand have been upgrading their existing base stations for UMTS and have applied to various City Councils for permission to build new 3G base stations. Vodafone New Zealand plans to launch the UMTS service by the end of 2005. AT&T Wireless (now a part of Cingular Wireless) has deployed UMTS in several cities. Though advancements in its network deployment have been delayed due to the merger with Cingular, Cingular has now announced plans to deploy W-CDMA along with HSDPA in 2005. TeliaSonera opened W-CDMA service in Finland October 13th 2004 with speeds up to 384 kbit/s. Availability only in main cities. Pricing is approx. 2€/MB. SK Telecom and KTF, two largest mobile phone service providers in South Korea, have each started offering W-CDMA service in December 2003. Due to poor coverage and lack of choice in handhelds, the W-CDMA service has barely made a dent in the Korean market. In Norway, Telenor introduced W-CDMA in major cities by the end of 2004, while their competitor, NetCom, followed suit a few months later. Both operators have full national coverage on EDGE. Maxis Communications and Celcom, two mobile phone service providers in Malaysia, started offering W-CDMA services in 2005. Technology W-CDMA may use unpaired or paired spectrum, though the current implementations of W-CDMA (i.e. FOMA and UMTS) all use a pair of 5MHz spectrum, one for uplink and one for downlink. *See Spread spectrum* for more information. FOMA uses 16 slots per radio frame, whereas UMTS uses 15 slots per radio frame.** °	TESTO PARALLELO INCASELLATO Scopri come è facile capire l'inglese se c'è a fianco la traduzione parallela incasellata!
	W-CDMA (Wideband Code Division Multiple Access) is a type of 3G cellular network.	W-CDMA (Accesso Multiplo a Divisione di Codice a banda larga) è un tipo di rete cellulare di terza generazione (3G.
	W-CDMA is the technology behind UMTS (a.k.a. 3GSM) and is allied with the 2G GSM standard.	W-CDMA è la tecnologia che sta dietro all'UMTS (anche noto come 3GSM) ed è collegato allo standard GSM di seconda generazione (2G GSM).
	More technically, W-CDMA 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).	Più tecnicamente, W-CDMA è un'interfaccia senza fili per le telecomunicazioni mobili 3G di tipo spread-spectrum a banda larga che utilizza la tecnica dell'accesso multiplo a divisione di codice (o CDMA, lo schema di multiplexing generalmente usato, da non confondere con lo standard CDMA).
	Brief History	Breve storia
	W-CDMA was developed by NTT DoCoMo as the air interface for their 3G network FOMA.	W-CDMA è stato sviluppato dalla NTT DoCoMo come interfaccia senza fili per la loro rete 3G FOMA.
	Later NTT Docomo submitted the specification to ITU as a candidate for the international 3G standard known as IMT-2000.	Successivamente la NTT DoCoMo ha presentato le specifiche all'ITU come candidate per lo standard internazionale 3G, noto come IMT-2000.
	The ITU eventually accepted W-CDMA as part of the IMT-2000 family of 3G standards.	L'ITU ha infine accettato W-CDMA come parte della famiglia degli standards 3G IMT-2000.
	Later, W-CDMA was selected as the air interface for UMTS, the 3G successor to GSM.	In seguito, W-CDMA è stato scelto come interfaccia senza fili per l'UMTS, successore di terza generazione dello standard GSM.
	Key Features	Caratteristiche principali
	• Supports two basic modes: FDD and TDD modes	• Supporta due modi di base: FDD e TDD
	• Employs coherent detection on uplink and downlink based on the use of pilot symbols	• Utilizza la rilevazione coerente su uplink e downlink basata sull'uso di simboli pilota
	• Inter-cell asynchronous operation	• Funzionamento asincrono d'inter-cella
	• Variable rate transmission: on a 10 ms frame basis	• Velocità di trasmissione variabile: su base 10ms per frame
	• Multicode transmission	• Trasmissione Multicode
	• Adaptive power control based on SIR	• Controllo adattivo di potenza basato sul SIR
	• Multiuser detection and smart antennas can be used to increase capacity and coverage	• La rilevazione multi-utente e antenne "intelligenti" possono essere utilizzate per aumentare la capacità e la copertura
	Misconceptions	Concetti errati
	Despite the similarity in name, W-CDMA has very little to do with CDMA. How little depends on the point of the viewer.	Nonostante la somiglianza del nome, W-CDMA ha molto poco a che fare con CDMA. Quanto poco dipende dall'osservatore.
	In the mobile phone world, the term CDMA can refer to either the Code Division Multiple Access spread spectrum multiplexing technique, or the CDMA family of standards developed by Qualcomm, including cdmaOne (or IS-95) and CDMA2000 (or IS-2000).	Nel mondo della telefonia mobile, il termine CDMA può riferirsi ugualmente sia alla tecnica di multiplexing 'spread spectrum' di accesso multiplo a divisione di codice, sia alla famiglia degli standards CDMA sviluppati da Qualcomm, compreso il cdmaOne (o IS-95) e il CDMA2000 (o IS2000).
	The CDMA multiplexing technique existed long before Qualcomm used it for its IS-95 protocol.	La tecnica di multiplexing CDMA esiste da molto prima che Qualcomm l'usasse per il relativo protocollo IS-95.
	However, this protocol is now widely referred to as "CDMA" for its principal characteristic of using the CDMA multiplexing scheme to share multiple connections divided by different codes (PN Sequences) over the same spectrum, as opposed to other spectrum division schemes (e.g. GSM's TDMA).	Tuttavia, a questo protocollo ci si riferisce ampiamente adesso come 'CDMA' per la sua principale caratteristica di usare lo schema di multiplexing CDMA per condividere connessioni multiple divise da codici differenti (sequenze PN) sullo stesso spettro, in contrapposizione ad altri schemi a divisione di spettro (per esempio TDMA del GSM).
	W-CDMA also uses the CDMA multiplexing technique, and has many similarities to the Qualcomm standards.	W-CDMA usa inoltre la tecnica di multiplexing CDMA, e presenta molte similarità con gli standards di Qualcomm.
	However W-CDMA is more than a multiplexing standard.	Tuttavia W-CDMA è qualcosa di più che uno standard di multiplexing.
	W-CDMA is a complete set of specifications, a detailed protocol that defines how a mobile phone communicates with the tower, how signals are modulated, how datagrams are structured, etc.	W-CDMA è un completo set di specifiche, un protocollo dettagliato che definisce come un telefono mobile comunica con il ripetitore, com'è modulato il segnale, come sono strutturati i datagram, etc.
	In summary:	Ricapitolando:
	• The term CDMA in the mobile world typically refers to the CDMA family of standards developed by Qualcomm.	• Il termine CDMA nel mondo della telecomunicazione mobile si riferisce alla famiglia degli standards CDMA sviluppati da Qualcomm.
	They are protocols, sets of defined specifications of mobile communications	Essi sono protocolli, insiemi di specifiche definite per le comunicazioni mobili
	• CDMA (the multiplexing technique) is used as the principle of the W-CDMA air interface protocol, as well as Qualcomm's CDMA protocols	• CDMA (la tecnica di multiplexing) è usata come principio del protocollo d'interfaccia senza fili W-CDMA, così come i protocolli CDMA di Qualcomm.
	• W-CDMA strictly refers to a mobile phone protocol with detailed specifications, as defined in IMT-2000	• W-CDMA si riferisce rigorosamente ad un protocollo di telefonia mobile con specifiche dettagliate, come definite in IMT-2000.
	• The W-CDMA protocol was developed independently of the CDMA protocol developed by Qualcomm	• Il protocollo W-CDMA è stato sviluppato indipendentemente dal protocollo CDMA, creato da Qualcomm
	• The CDMA family of standards (including cdmaOne and CDMA2000) are not compatible with the W-CDMA family of standards	• La famiglia degli standards CDMA (includendo cdmaOne e CDMA2000) non è compatibile con la famiglia degli standards W-CDMA
	Real-World Implementations	Implementazioni nel mondo reale
	The world's first commercial W-CDMA service, FOMA, was launched by NTT DoCoMo in Japan in 2001.	Il primo servizio commerciale W-CDMA del mondo, FOMA, è stato lanciato da NTT DoCoMo in Giappone nel 2001.
	FOMA is not compatible with UMTS.	FOMA non è compatibile con lo standard UMTS.
	But the efforts for migrating the FOMA specifications to UMTS are indicated by Japan.	Ma gli sforzi per far migrare le specifiche FOMA verso UMTS sono evidenziati dal Giappone.
	J-Phone Japan (now Vodafone) soon followed by launching their own W-CDMA based service, originally branded "Vodafone Global Standard" and claiming UMTS compatibility.	La giapponese J-Phone (adesso Vodafone) ha subito seguito lanciando il suo proprio servizio basato su W-CDMA, originariamente chiamato "Standard Globale Vodafone" e sostenendo la compatibilità con UMTS.
	The name of the service was changed to "Vodafone 3G" in December 2004.	Nel dicembre del 2004 il nome del servizio è stato cambiato in "Vodafone 3G".
	Beginning in 2003, Hutchison Whampoa gradually launched their upstart UMTS networks (simply called 3) worldwide.	All'inizio del 2003, la Hutchinson Whampoa ha lanciato gradualmente le sue nuovissime* reti UMTS (chiamate semplicemente 3) in tutto il mondo.
	Most Western European GSM providers plan to offer UMTS sometime in the future, though few have committed to an actual timeline.	La maggior parte dei provider GSM dell'Europa occidentale intendono offrire il servizio UMTS in un futuro prossimo, sebbene pochi si siano impegnati a definire una scaletta temporale.
	Some of them have begun launching UMTS networks at the end of 2003.	Alcuni di loro hanno cominciato a lanciare le reti UMTS alla fine del 2003.
	Vodafone launched several UMTS networks in Europe in February 2004.	La Vodafone ha lanciato diverse reti UMTS in Europa nel febbraio del 2004.
	Vodafone also has plans to launch UMTS networks in other countries, including Australia and New Zealand.	Vodafone intende anche lanciare reti UMTS in altri paesi, compresa l'Australia e la Nuova Zelanda.
	Vodafone New Zealand have been upgrading their existing base stations for UMTS and have applied to various City Councils for permission to build new 3G base stations.	Vodafone New Zealand sta aggiornando le sue stazioni base per l'UMTS e sta richiedendo alle varie giunte comunali il permesso per la costruzione di nuove stazioni base 3G.
	Vodafone New Zealand plans to launch the UMTS service by the end of 2005.	Vodafone New Zealand intende lanciare il servizio UMTS per la fine del 2005.
	AT&T Wireless (now a part of Cingular Wireless) has deployed UMTS in several cities.	La AT&T Wireless (attualmente parte di Cingular Wireless) ha portato l'UMTS in diverse città.
	Though advancements in its network deployment have been delayed due to the merger with Cingular, Cingular has now announced plans to deploy W-CDMA along with HSDPA in 2005.	Nonostante i suoi progressi nello sviluppo della rete siano stati ritardati dalla fusione con Cingular, Cingular ha ora annunciato l'intenzione di sviluppare W-CDMA insieme ad HSDPA nel 2005.
	TeliaSonera opened W-CDMA service in Finland October 13th 2004 with speeds up to 384 kbit/s.	TeliaSonera ha inaugurato i servizi W-CDMA in Finlandia il 13 ottobre del 2004 con una velocità massima di 384 kbit/s.
	Availability only in main cities.	Disponibile solo nelle principali città.
	Pricing is approx. 2€/MB.	Il prezzo si aggira intorno ai 2€/MB.
	SK Telecom and KTF, two largest mobile phone service providers in South Korea, have each started offering W-CDMA service in December 2003.	SK Telecom e KTF, due grandi gestori di servizi telefonici della Corea del Sud, hanno iniziato entrambe ad offrire servizi W-CDMA nel dicembre del 2003.
	Due to poor coverage and lack of choice in handhelds, the W-CDMA service has barely made a dent in the Korean market.	A causa della scarsa copertura e della mancanza di scelta per quanto riguarda i telefoni cellulari, i servizi W-CDMA hanno influenzato in maniera minima il mercato coreano.
	In Norway, Telenor introduced W-CDMA in major cities by the end of 2004, while their competitor, NetCom, followed suit a few months later.	In Norvegia, la Talenor ha introdotto il W-CDMA nelle maggiori città a partire dalla fine del 2004, mentre il suo concorrente, la NetCom, l'ha subito seguita qualche mese dopo.
	Both operators have full national coverage on EDGE.	Entrambe gli operatori hanno una totale copertura nazionale con la tecnologia EDGE.
	Maxis Communications and Celcom, two mobile phone service providers in Malaysia, started offering W-CDMA services in 2005.	La Maxis Communications e la Celcom, due gestori di servizi di telefonia mobile della Malesia, hanno iniziato ad offrire servizi W-CDMA nel 2005.
	Technology	Tecnologia
	W-CDMA may use unpaired or paired spectrum, though the current implementations of W-CDMA (i.e. FOMA and UMTS) all use a pair of 5MHz spectrum, one for uplink and one for downlink.	W-CDMA può usare sia bande paired (appaiate) che unpaired (non appaiate), sebbene le correnti implementazioni di W-CDMA (per esempio FOMA e UMTS) usino tutte bande appaiate di 5MHz entrambe, una in uplink ed una in downlink.
	See Spread spectrum for more information.	Vedi Spread spectrum per maggiori informazioni.
	FOMA uses 16 slots per radio frame, whereas UMTS uses 15 slots per radio frame.	FOMA utilizza 16 slots per frame radio, mentre UMTS ne usa 15 per frame radio.