3G Whiz

With the rapid emergence and popularity of a mobile information culture, operators are faced with the challenge of expanding and evolving their networks to support the convergence of the Internet and voice communications. This challenge is particularly evident in digital wireless, where subscriber growth has surpassed all expectations.

Over the past year alone, CDMA, for example, has more than doubled its subscriber base. In order to support this growth, operators are seeking a solution that can meet the increased voice-capacity demands and provide new data services while still preserving their current investments. These 3G services and features include Internet access, e-mail, video conferencing and interactive news delivery.

Along with capacity constraints, the costs of acquiring spectrum and equipment to support faster services also affect an operator's success in the marketplace. Operators are looking to 3G technologies to address these emerging mobile information needs. One option is to evolve from today's cdmaOne to 3G via cdma2000. The first phase of cdma2000, commonly known as 1X, uses existing spectrum more efficiently and addresses operators' concerns about increased capacity and data speeds.

SUPER EFFICIENCY Today's cdmaOne already supports some data services at speeds of 14.4kb/s and 64kb/s for the IS-95A and IS-95B standards, respectively, allowing operators to assess demand for consumer data services today. However, exponential subscriber growth, increased data traffic and demand for more throughput are forcing operators to examine near-term support of faster data speeds. Rates from 144kb/s to 2Mb/s will be required to support new multimedia applications.

Cdma2000 1X's other benefits include:

* Quantity and quality. Cdma2000 1X doubles capacity within the same 1.25MHz band by applying improved modulation techniques, better forward-power control and efficient coding. Voice quality is improved by using separate channels for control signals so voice-traffic frames on the traffic channel aren't interrupted. The Enhanced Medium Access Control (E-MAC) feature allows different users and applications to be assigned different priorities. For example, delay-sensitive applications such as streaming video or audio can be given priority over latency-tolerant applications such as e-mail.

* More Capacity. Cdma2000 1X supports smart antennas and other enhancements for improving coverage and capacity. Cdma2000 1X uses auxiliary pilots to create a coverage sub-sector within a sector. The high capacity sub-sector, or spot beam, provides additional capacity without significant investment in new infrastructure. This approach is ideal for hot spots requiring dynamic capacity: stadiums, malls and conference centers. Using smart antennas can allow spot-beam tracking of users for dedicated services.

* Cost-effective migration. True backward and forward compatibility between cdma2000 1X and cdmaOne protects the investment in the existing infrastructure. Five MHz of spectrum can accommodate three cdmaOne or three cdma2000 1X carriers. Based on network demand and capital availability, operators can choose which cell sites to upgrade from cdmaOne to cdma2000 1X. The ability to use both cdmaOne and cdma2000 1X carriers also eliminates the need to purchase additional spectrum.

* More throughput. Cdma2000 is designed to provide data rates from 144kb/s with cdma2000 1X to 2Mb/s with cdma2000 3X, the second phase of cdma2000. This increase is achieved by implementing dynamic-rate Supplemental Channels: Depending on the application requirements, the rates can be increased or decreased, improving the air-link-resource utilization.

The use of higher data rates for voice over IP (VoIP) and emerging multimedia applications requires sophisticated prioritization and scheduling of data packets. Cdma2000 1X uses E-MAC to address these quality-of-service issues.

THE CORE NETWORK Cdma2000 radio upgrades are relatively simple compared to migrating the rest of the network to support the new services. Three key issues are evolving the backbone network to a packet network, developing data applications, content and services, and introducing new 3G terminals for customers.

The transition to a cdma2000 1X network requires an efficient core-network delivery mechanism for voice and data. The current cdmaOne core networks need to be upgraded to include a packet-data-serving node (PDSN) and an authorization, authentication and accounting server. The packet core network will support both home agent and foreign agent for mobile IP functionality.

Open radio-packet interfaces between the BSC and the PDSN give operators the choice of a multivendor environment between the base-station subsystem and the core network. Several vendors also support the evolution of the Interoperability Specification, an interface between the MSC and the BSC, to support 3G services. Open interfaces give operators more equipment options and allow them to provide a more competitive product.

Much work is under way to develop applications and services for operators to implement and market on their cdmaOne and, eventually, cdma2000 networks. Second-generation networks were designed primarily to deliver better-quality voice communications than analog. However, today's 2G technology already is delivering low-speed data services, including push services.

With the introduction of cdma2000 1X in 2001, information services will include high-bandwidth services such as e-mail, Web browsing, e-commerce, VoIP and multimedia. Over the next few years, users' voice and data requirements will continue to evolve as 3G networks debut. One example is increased use of image transfers.

HANDSETS EVOLVE The final piece of the 3G puzzle is the capability and availability of terminals to provide the enhanced functionality. Current cdmaOne terminals will function on cdma2000 1X networks, but they won't provide services that require higher data rates or help improve network capacity. Cdma2000 1X terminals will look and feel much like today's high-end handsets with two exceptions: an emphasis on smaller, sleeker, more ergonomic terminals and backwards-compatibility with cdmaOne.

3G terminals also will include increases in talk and standby times of between 50% and 100%, color screens, WAP and text input via touch or graphics +/- la the Palm Pilot. Voice activation, currently marketed as a high-end feature, likely will become more standard in the next generation of terminals.

With cdma2000 1X, operators can effectively position themselves in an ever-changing wireless world. Its state-of-the-art features and capabilities will provide operators with increased revenue and cutting-edge competitiveness in today's dynamic voice and data markets. Perhaps best of all, these improvements still protect the current investment and require little incremental investment to migrate to 3G.

Mobile IP, the Internet standard for mobility, enhances basic packet-data services on CDMA networks by offering seamless mobility to data users.

Basic packet data uses IP to transmit packets over a network and is optimal for applications such as e-mail and Web browsing that send and receive data in bursts. CdmaOne (IS-95 CDMA) networks currently support packet-data services at speeds of 14.4kb/s and 64kb/s.

Mobile IP allows users to maintain a continuous data connection and retain a single IP address while traveling between BSCs or roaming on other networks. Maintaining a consistent IP address gives the user transparent access to corporate intranets and the freedom to roam seamlessly between wired home networks and wireless CDMA networks.