As personal wireless connectivity is becoming more widespread and more complex, the ability to provide service on the many levels available to wireless users using a variety of devices is also rapidly becoming much more complex. To accommodate these challenges and to face a future where there are no barriers to access using a handheld device, engineers are investigating what measures are needed to create a "universal communicator," a device that is capable of communicating regardless of the connection options available to the user.
There are several options for personal wireless communication currently available through service providers. The majority of users connect via cellular connections: either using the GSM family of networks (GSM, GPRS, EDGE, UMTS), or the CDMA family of cellular networks (CDMA, CDMA 2000, 1xRTT, EV-DO, EV-DV). However, with the advent of wireless standards for WLAN and WMAN, deployment of these networks is steadily increasing in enterprises, public "hotspots" and even within homes. Although widespread deployment is still a few years away, these networking options are open to users now.
Additionally, various Wireless Personal Area Network (WPAN) technologies are emerging as well. Bluetooth is well on its way to becoming the most widely deployed WPAN technology in handsets and other devices -- with projections of nearly 300 million Bluetooth-enabled devices in the marketplace in 2007 (WLAN and Bluetooth PCB Assembly Update: Beyond the Hype, Forrester Research, June 16, 2003). Looking a few years down the road, Ultra Wideband (UWB) holds great promise as the next major technology for high-bandwidth wireless personal area connectivity.
Finally, a number of other wireless technologies are in the midst of being tested and/or deployed. For example, GPS is slated to ship in over 10 million phones this year, and several major device manufacturers are already shipping products with TV and/or radio receivers. Several operators and OEMs are also experimenting with including digital video broadcast (DVB) receivers in handsets, in some cases with GPRS used as a back channel to enable interactive data delivery (otherwise known as "datacasting").
Designs for future handheld devices will require that engineers consider each of these technologies and the challenges that each of these technologies pose in creating a device that can communicate regardless of the networking technology available.
A New Class of Device
Meeting both the opportunities and challenges of a heterogeneously-networked environment will require that handheld devices evolve considerably -- from the limited (often fixed-function and fixed-network) devices that predominate today, to powerful, flexible devices that can intelligently interact with multiple, heterogeneous networks and services.
This evolutionary process will result in the development of a new class of handheld device, dubbed a "universal communicator." A universal communicator-class device is a flexible, powerful personal communication device that provides users with transparent access to any available network, at any time, including the ability to seamlessly roam across those networks. Such a device must also provide support for key usage models that are made possible by a mixed-network environment. These usage models include:
Infofueling (smart data transfers using best available/most appropriate network)
Simultaneous voice and data sessions
Rich media that scales across networks (for example, video quality increases in a higher-bandwidth environment)
Cross-network voice, including support for seamless handoff
Location-based services
The focus of Intel's prototype device is by its capabilities rather than by a specific form factor. Users will continue to demand many different mobile form factors suited to their specific needs and lifestyles. For this reason, Intel efforts with the "Universal-communicator" device prototype are directed at delivering the overall platform capabilities needed to enable such devices.
Technology Challenges
Enabling such ubiquitously-connected devices poses numerous difficult technology challenges. These include:
Multiple Radio Integration and Coordination: Building the handset (or other device) begins with the challenge of integrating multiple radios.
Intelligent Networking -- Seamless Roaming and Handoff: Users will expect to roam within and between networks like they do with their cell phone.
Power Management: As handsets and other devices evolve to run more rich applications, power management will become an even greater challenge.
Support for Cross Network Identity and Authentication: Providing a trusted, efficient and usage-model appropriate means of establishing identity is one of the key issues in cross-network connectivity.
Support for Rich Media Types: The addition of a high-bandwidth broadband wireless connection, such as a WLAN or some of the forthcoming UMTS or EVDV/O cellular networks, will open up new opportunities for the delivery of rich media to handheld devices.
Flexible, Powerful Computing Platform: The foundation of a universal communicator-class device must be a flexible, powerful, general-purpose processing platform.
Overall Device Usability: The final challenge inherent in building a mixed-network device is usability.
To address these challenges, Intel engineers are developing a suite of key client technologies that can enable transparent, ubiquitous connectivity, as well as an architecture that pulls that set of technologies together into a coherent whole. Intel has dubbed that suite of technologies and the associated architectural framework, Adaptive Communication Technologies (ACT). As Intel develops these building blocks, Intel will diffuse this technology either via Intel silicon and platforms, or through cooperative efforts with other industry leaders and/or application developers.
The Prototype Concept
As a starting point for ACT development efforts, Intel has developed a first-generation universal communicator handset prototype. This prototype not only demonstrates the ability to successfully integrate multiple network access capabilities (in this case WWAN+WLAN) in a handset, but also demonstrates several key technologies and design principles that Intel believes are applicable to a larger class of universal communicator-class devices.
The universal communicator prototype demonstrates key usage models for mixed-network handheld clients, including:
Simultaneous data and voice sessions
Infofueling -- smart data transfers using best available network
Rich media that scales across network connections
Voice (cellular and VOIP) across multiple networks
A Feature-Rich Handheld Device
The prototype incorporates many advanced features and technologies that enable important usage models
Intel PCA processor -- Based on Intel XScale technology, this processor provides a powerful, general-purpose platform upon which to build wireless applications and makes possible many advanced features, including Voice-Over-IP, high-quality audio and video, and enhanced 3D gaming.
Integrated 802.11b and GSM/GPRS radios, with component decoupling -- The UC handset prototype uses an embedded 802.11b module for onboard WLAN capability. The module implementation is a complete solution on a PCB substrate, which comes with fully shielded and attaches to the board via BGA technology. It supports the PCMCIA interface for system control and requires the addition of only address and data bus buffering components to isolate from the main system bus as well minimal control circuitry and a discrete antenna. The implementation includes power supply isolation through an LDO regulator and uses an internal chip antenna.
The GSM/GPRS solution is implemented using an Intel-developed GSM/GPRS module. This module supplies the complete baseband/RF solution and requires the addition of a discrete, external antenna. System connectivity/control is achieved via a high-speed serial interface, and our design implements a separate audio codec subsystem for speaker/microphone and ringer components. The GEM module is a complete solution on a PCB substrate which is fully shielded.
Mobility Management Driver Stack (MMDS) -- Mobility management is the ability for a client device's applications and operating system to discover the in-proximity wireless network environment and then interact with the networks within that environment in complex ways.
The MMDS stack in the current prototype supports a subset of three general categories of functionality: heterogeneous wireless network detection; quality of service characterization; and ultimately support for seamless hand-offs between networks. By taking a cross-network perspective (IP or otherwise) to these problems the MMDS approach is different, albeit complementary, to single-protocol approaches such as Mobile IP. The remainder of the section describes in more detail the work Intel has done in the prototype relative to these functional categories.
Voice Call Unification Architecture (VCUA) -- In the special case of a voice call, support for uninterrupted call audio is required in addition to network hand-off to deliver a seamless user experience. The prototype VCUA in the prototype abstracts device audio resources so that the audio session continues even if the underlying audio hardware changes.
Taken together, the VCUA and the MMDS enable seamless call handoff. In the prototype, a specially-modified version of the Telesym SymPhone client software utilizes these capabilities to deliver a relatively seamless call handoff between networks.
Antenna layout, shielding, and optimal spatial positioning reduce analog radio interference -- The prototypes uses the Galtronics "Wind Back" antenna to provide optimal GSM reception which is shielded to avoid analog radio interference.
A chip antenna was used for the internal IEEE 802.11b subsystem and used similar implementation techniques as those used for the GSM antenna interface: plane voids, CPW, routing obstructs on all trace layers, etc.
Advanced media capabilities -- The handset prototype contains a high-performance, software H.264/AVC video decoder for playback of local and streaming content over a variety of network connections. The decoder is compliant with the Baseline Profile, and is optimized for Intel Wireless MMX technology.
Usability -- The prototype contains a number of technologies designed to increase usability for wireless applications such as a Kodak NuVue OLED (organic light-emitting diodes) display which requires no backlights and provides clearer images and crisper video.
The UC handset prototype also features a Fastap keypad. The Fastap keypad hardware and software provides direct-entry alphanumeric input, allowing mobile phone users to create text and multimedia messages quickly and intuitively.
SD card slot -- Support for SD cards provides the opportunity for additional storage -- critical for many data-intensive wireless applications.
Summary
Building a handheld device that can be considered a "universal communicator" will require that engineering teams consider the many challenges that will face its development. The result of that evolutionary process will be a new class of devices that will use multiple networks to transparently connect users with information and services.
Intel is developing a core set of technology building blocks -- called Adaptive Communication Technologies -- that will enable seamless, transparent connectivity and advance efforts at universal connectivity and communication. Concept platforms like the Universal Communicator handset prototype provide a research platform for the development, integration, and validation of these technologies. In addition, Intel is working electronic assembly with the high-tech industry to develop and distribute the key technologies and research required to make universal, transparent connectivity a reality.