3rd Generation Wireless Systems (3G), a simple discussion

Third Generation (3G) mobile devices and services will transform wireless communications into on-line, real-time connectivity. 3G wireless technology will allow an individual to have immediate access to location-specific services that offer information on demand. The first generation of mobile phones consisted of the analog models that emerged in the early 1980s. The second generation of digital mobile phones appeared about ten years later along with the first digital mobile networks. During the second generation, the mobile telecommunications industry experienced exponential growth both in terms of subscribers as well as new types of value-added services. Mobile phones are rapidly becoming the preferred means of personal communication, creating the world's largest consumer electronics industry.

The rapid and efficient deployment of new wireless data and Internet services has emerged as a critical priority for communications equipment manufacturers. Network components that enable wireless data services are fundamental to the next-generation network infrastructure. Wireless data services are expected to see the same explosive growth in demand that Internet services and wireless voice services have seen in recent years.

Third Generation (3G) Wireless Networks 3G wireless technology represents the convergence of various 2G wireless telecommunications systems into a single global system that includes both terrestrial and satellite components. One ofthe most important aspects of 3G wireless technology is its ability to unify existing cellular standards, such as CDMA, GSM, and TDMA, under one umbrella. The following three air interface modes accomplish this result: wideband CDMA, CDMA2000 and the Universal Wireless Communication (UWC-136) interfaces. Wideband CDMA (W-CDMA) is compatible with the current 2G GSM networks prevalent in Europe and parts of Asia. W-CDMA will require bandwidth of between 5Mhz and 10  Mhz, making it a suitable platform for higher capacity applications. It can be overlaid onto existing GSM, TDMA (IS-36) and IS95 networks. Subscribers are likely to access 3G wireless services initially via dual band terminal devices. W-CDMA networks will be used for high-capacity applications and 2G digital wireless systems will be used for voice calls.

The second radio interface is CDMA2000 which is backward compatible with the second generation CDMA IS-95 standard predominantly used in US. The third radio interface, Universal Wireless Communications – UWC-136, also called IS-136HS, was proposed by the TIA and designed to comply with ANSI-136, the North American TDMA standard. 3G wireless networks consist of a Radio Access Network (RAN) and a core network. The core network consists of a packet-switched domain, which includes 3G  SGSNs and  GGSNs, which provide the same functionality that they provide in a GPRS system, and a circuit-switched domain, which includes 3G MSC for switching of voice calls. Charging for services and access is done through the Charging Gateway Function (CGF), which is also part of the core network. RAN functionality is independent from the core network functionality.  The access network provides a core network technology independent access for mobile terminals to different types of core networks and network services. Either core network domain can access any appropriate RAN service; e.g. it should be possible to access a “speech” radio access bearer from the packetswitched domain. Below is the achitecture of third generation  wireless systems.

 Evolution to 3G Wireless Technology

Initial coverage

Initially, 3G wireless technology will be deployed as "islands" in business areas where more capacity and advanced services are demanded. A complete evolution to 3G wireless technology is mandated by the end  of  2000 in Japan (mostly due to capacity requirements) and by the end of 2001 in Europe. NTT DoCoMo is deploying 3G wireless services in Japan in the third quarter  of 2000. In contrast, there is no similar mandate in North America and it is more likely that competition will drive the deployment of 3G wireless technology in that region. For example,

Nextel Communications has announced that it will be deploying 3G wireless services in North America during the fourth quarter of 2000. The implementation of 3G wireless systems raises several critical issues, such as the successful backward compatibility to air interfaces as well as to deployed infrastructure.

Interworking with 2G and 2G+ Wireless Networks

The existence of legacy networks in most regions of the world highlights the challenge that communications equipment manufacturers face when implementing next-generation wireless technology.  Compatibility and interworking between the new 3G wireless systems and the old legacy networks must be achieved in order to ensure the acceptance of new 3G wireless technology by service providers and end-users.

The existing core technology used in mobile networks is based on traditional circuit-switched technology for delivery of voice services. However, this traditional technology is inefficient for the delivery of multimedia services. The core switches for next-generation of mobile networks will be based on packet-switched technology which is better suited for data and multimedia servicesThird Generation (3G) mobile devices and services will transform wireless communications into on-line, real-time connectivity. 3G wireless technology will allow an individual to have immediate access to location-specific services that offer information on demand. The first generation of mobile phones consisted of the analog models that emerged in the early 1980s. The second generation of digital mobile phones appeared about ten years later along with the first digital mobile networks. During the second generation, the mobile telecommunications industry experienced exponential growth both in terms of subscribers as well as new types of value-added services. Mobile phones are rapidly becoming the preferred means of personal communication, creating the world's largest consumer electronics industry.

The rapid and efficient deployment of new wireless data and Internet services has emerged as a critical priority for communications equipment manufacturers. Network components that enable wireless data services are fundamental to the next-generation network infrastructure. Wireless data services are expected to see the same explosive growth in demand that Internet services and wireless voice services have seen in recent years.

Third Generation (3G) Wireless Networks 3G wireless technology represents the convergence of various 2G wireless telecommunications systems into a single global system that includes both terrestrial and satellite components. One ofthe most important aspects of 3G wireless technology is its ability to unify existing cellular standards, such as CDMA, GSM, and TDMA, under one umbrella. The following three air interface modes accomplish this result: wideband CDMA, CDMA2000 and the Universal Wireless Communication (UWC-136) interfaces. Wideband CDMA (W-CDMA) is compatible with the current 2G GSM networks prevalent in Europe and parts of Asia. W-CDMA will require bandwidth of between 5Mhz and 10  Mhz, making it a suitable platform for higher capacity applications. It can be overlaid onto existing GSM, TDMA (IS-36) and IS95 networks. Subscribers are likely to access 3G wireless services initially via dual band terminal devices. W-CDMA networks will be used for high-capacity applications and 2G digital wireless systems will be used for voice calls.

The second radio interface is CDMA2000 which is backward compatible with the second generation CDMA IS-95 standard predominantly used in US. The third radio interface, Universal Wireless Communications – UWC-136, also called IS-136HS, was proposed by the TIA and designed to comply with ANSI-136, the North American TDMA standard. 3G wireless networks consist of a Radio Access Network (RAN) and a core network. The core network consists of a packet-switched domain, which includes 3G  SGSNs and  GGSNs, which provide the same functionality that they provide in a GPRS system, and a circuit-switched domain, which includes 3G MSC for switching of voice calls. Charging for services and access is done through the Charging Gateway Function (CGF), which is also part of the core network. RAN functionality is independent from the core network functionality.  The access network provides a core network technology independent access for mobile terminals to different types of core networks and network services. Either core network domain can access any appropriate RAN service; e.g. it should be possible to access a “speech” radio access bearer from the packetswitched domain.

What Is Special about EDGE?

EDGE is a new modulation scheme that is more bandwidth efficient than the GMSK modulation

scheme used in the GSM standard. It provides a promising migration strategy for HSCSD and

GPRS. The technology defines a new physical layer: 8−PSK modulation, instead of GMSK. 8−PSK enables each pulse to carry 3 bits of information versus the GMSK 1−bit−per−pulse rate. Therefore,EDGE has the potential to increase the data rate of existing GSM systems by a factor of three.

UMTS is a part of the ITU's IMT−2000 vision of a global family of 3G mobile communications

systems. UMTS will play a key role in creating the future mass market for high−quality wireless

multimedia communications that will approach 2 billion users worldwide by the year 2010.

UMTS is a modular concept that takes full advantage of the trend of converging existing and future information networks, devices, and services, and the potential synergies that can be derived from such convergence. UMTS will move mobile communications forward from where we are today into the 3G services and will deliver speech, data, pictures, graphics, video communication, and other wideband information direct to people on the move. UMTS is one of the major new 3G mobile communications systems being developed within the framework, which has been defined by the ITU and is known as IMT−2000.

WCDMA is an ITU standard derived from CDMA and is officially known as IMT−2000 direct spread. WCDMA is a 3G mobile wireless technology offering much higher data speeds to mobile and portable wireless devices than commonly offered in today's market. WCDMA can support mobile/portable voice, images, data, and video communications at up to 2 Mbps (local area access) or 384 Kbps (wide area access). The input signals are digitized and transmitted in coded, spread−spectrum mode over a broad range of frequencies. A 5 MHz wide carrier is used, compared with a 200 kHz wide carrier for narrowband CDMA.

Mobile Internet — A Way of Life

The mobile Internet is about to enter our daily lives in a big way. It will change the way we keep in touch with our friends and family, the way we do business, the way we shop, the way we access entertainment, and the way we conduct our personal finances.

The Internet is already a part of daily life for most of us, giving us access to a vast range of

information and online services from our desktop computers. As a way of conducting business, it is also of growing importance to the global economy. Unlike today's fixed Internet, the mobile Internet will give us access to these services and applications wherever we are, whenever it suits us, from personal mobile devices.

Sources:

http://www.satmagazine.com

http://www.dryaseen.pk

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