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Cingular Wireless UMTS /, United States of America

Key Data

In November 2004 Cingular Wireless announced that it would commercially launch UMTS (Universal Mobile Telecommunications System) high-speed downlink packet access (HSDPA) services in 2005. HSDPA is an enhanced version of UMTS which will ultimately support theoretical maximum peak data speeds of up to 14.4Mbps. The company intends to build upon AT&T Wireless's six-market UMTS launches to begin the expansion of a major city and suburban 3G network during 2005, which should allow nationwide coverage in most metropolitan areas by the end of 2006. Cingular Wireless's closest competitors in 3G technology in the US are Verizon Wireless and Sprint PCS.

Cingular Wireless, based in Atlanta, is the largest wireless carrier in the United States serving more than 49.1 million subscribers (figure reported January 2005). The company is a joint venture between SBC Communications Inc and BellSouth, and has the largest digital voice and data network in the US, surpassing Verizon Wireless as the biggest US wireless provider in October 2004 after acquiring AT&T Wireless.


The network expansion will be handled by Lucent Technologies, Ericsson and Siemens. Nortel Networks are not involved in this network expansion even though they provided the core system technology for the AT&T Wireless UMTS rollout early in 2004, which Cingular Wireless now controls. The four-year contract is important to Lucent Technologies because it is the company's first major UMTS project.

Each of the suppliers will build a section of the network and supply the HSDPA software upgrades for their particular part. The investment for the Siemens portion of the contract is estimated at over $1 billion. Cingular has not released an overall figure for the cost of the network expansion.

The Cingular UMTS / HSDPA network will initially support data speeds of up to 3.6Mbps (the top speed of the first generation of HSDPA-ready devices expected to become available during 2005). Speeds will increase and will ultimately approach the theoretical maximum of 14.4Mbps as more advanced devices become available. At the same time Cingular has awarded a contract to Nokia to enhance its existing GSM / GPRS / EDGE networks and possibly provide support for additional 3G expansions in the future. Nokia, Siemens, Motorola and LG have all committed to deliver UMTS PCS handsets in 2005 for use on the new network.


Before the contracts were awarded for the HSDPA network Cingular Wireless had already carried out extensive field trials on the technology (announced in January 2004) with the Lucent Technology UMTS / HSDPA system in Atlanta in mid-2004. This trial used the spectrum in the 1.9GHz band, and end-to-end network equipment from Lucent, including Merlin U520 UMTS PC modem cards, which were developed by Lucent Technology and Novatel Wireless. HSDPA is really only a software upgrade from conventional UMTS gear.

The trial network in Atlanta gave over-the-air data rates of more than 3Mbps, and also supported a wide variety of high-bandwidth multimedia services including high-quality streaming video as well as fast downloads of high-resolution images and other large files. The trial was also able to demonstrate reductions in transmission delays that would enable interactive services and applications such as multi-player video gaming in the mobile market.

The trial Lucent network used their end-to-end commercial UMTS solution, which included Lucent's Flexent OneBTS base stations (Node Bs), which are HSDPA-ready, Flexent Radio Network Controllers (RNC), as well as the UMTS packet core solution, including the Lucent Flexent Serving GPRS Support Node (SGSN), and Gateway GPRS Support Node (GGSN), along with an HSDPA test terminal.


Voice over Internet Protocol (VoIP), also known as Internet Voice, is a technology that allows telephone calls to be made using a broadband Internet connection instead of a normal phone line. Some services using VoIP may only allow the user to call other people using the same service, but others may allow the user to call anyone who has a telephone number - including local, long distance, mobile and international numbers. In addition, while some services only work over the computer or a special VoIP phone, other services allow the use of a traditional phone through an adaptor.

VoIP gives users the ability to have simultaneous voice and data sessions, so that they can use a handset to make a call at the same time they are checking e-mail or browsing the internet at high speeds. HSDPA has a theoretical download ceiling of 14Mbps and its low latency (shorter 2msec frame length supports a significantly reduced round trip time) gives it additional speed advantages, allowing for faster loading of Web content and even the possibility of this new VoIP service.


HSDPA is a packet based data service operating in WCDMA downlink. The system does not rely on huge and expensive hardware infrastructure upgrades, but it is a much less expensive software upgrade. The data transmission speeds allow for a theoretical maximum of 14.4Mbps but at the current time this is more likely to be about 4Mbps.

According to 3rd Generation Partnership Project (3GPP) standards, HSDPA Release 4 specifications provide efficient IP support enabling provision of services through an all-IP core network. Release 5 specifications focus on HSDPA to provide data rates up to approx. 10Mbps. MIMO (Multiple-Input Multiple-Output) systems will be incorporated in Release 6 specifications, which will support even higher data transmission rates of up to 20Mbps.

Further HSDPA enhancements include Adaptive Modulation and Coding (AMC), Multiple-Input Multiple-Output (MIMO), Hybrid Automatic Request (HARQ), fast cell search, and advanced receiver design. This enables support of packet-based multimedia services such as video conferencing over a video phone. By 2007 HSDPA will be the new broadband standard.