TI claims phone power breakthrough

Despite the expected release of dual-mode Wi-Fi/cellular handsets later this year, Finnish giant Nokia is more concerned about improved power technology than hybrid devices.

That, at least, is according to one senior executive who says that such an improvement is necessary to enable not just Wi-Fi but multimode and WiMAX phones, and usher in an entirely new breed of ubiquitous mobile devices.

The electronics vendors are racing to improve power management and compactness so that they can ride that next wave. Texas Instruments, an increasingly close ally of Nokia, has made a major breakthrough with its Digital RF technology. Highly-integrated architectures like this will be essential to make the next generation of handsets possible, but Nokia is concerned that battery technology is not keeping pace.

Nokia is almost certain to make use of the emerging platform as it develops products - which it refuses to categorize as "phones" - which act as everything from entertainment hub to business PC and adapt intelligently to the most appropriate wireless network in range.

Brave new world

Both TI and Intel are working on architectures and chipsets to support multiple wireless protocols, although they are taking very different approaches: TI is focusing on fast, miniaturised dedicated processors; and Intel on putting all the work into a unified software defined radio. Its pet project is the adaptive digital silicon radio, which - in several years' time - will provide intelligent roaming between networks.

The first step to this brave new world of multinetworks will be the Wi-Fi/cellular phone - perhaps also offering Bluetooth, as TI's Wanda platform does. Motorola is set to be the first major mobile phone maker with dual-mode handsets and Nokia's CEO Jorma Ollila recently told Finnish equity broker Mandatum that his company is "close to launching mobile phones enabling users to switch between the high-speed data services of Wi-Fi and the more traditional cellular functions".

TI's Digital RF Processor breakthrough

Targeting these emerging markets, the new TI technology is the Digital RF Processor (DRP) architecture, which TI claims will halve space and power consumption in a wireless device compared to traditional analogue chipsets. The company demonstrated the platform at this week's International Solid State Circuits (ISSC) conference. It said it was already being demonstrated in GPRS/GSM/Bluetooth handsets and would be put into WLAN phones later this year, further offering 3G in 2005.

"The processing of radio signals with digital logic can significantly shift the paradigm for embedding wireless communications by making it easier to implement and to scale," said Dr Hans Stork, TI's chief technology officer. By greatly simplifying RF processing in this way, complex handsets can be made more compact and cheaper, and far less power-hungry, all critical factors for carrier and user adoption. The technology will be combined with TI's existing developments in low power, single-chip GSM and Wi-Fi.

DRP

In contrast to Intel's software stance, TI believes that dedicated processors for each connection are faster and less power-hungry if they can be shrunk down sufficiently to be combined in one handset. The DRP is a key element of TI's promised single-chip wireless solution, slated for late 2005, which will support cellular, Wi-Fi, Bluetooth and potentially WiMAX.

CDMA, which coexists less readily with other protocols, will have to wait until 2006, although TI was insistent that it would take its DRP into this market. TI is Nokia's primary partner for CDMA and the main challenger to the technology's patent holder Qualcomm.

TI is now testing silicon that combines the DRP with the baseband processor and power management functions, only leaving the battery charging, power amplifier and flash memory functions off-chip.

Negatives about the integrated baseband-RF approach include a greater difficulty in changing the feature set of a phone. However, as TI moves to more advanced manufacturing processes that allow for even greater integration and cost reduction, there should be strong take-up at the more complex end of the handset market - multimode and heavy multimedia designs. By freeing up board space, phonemakers can add more customised functions in their designs.

The battery challenge

Nokia chief technology officer Yrjö Neuvo was less starry-eyed in his own presentation at ISSC, claiming that battery technology cannot currently keep up with the increasing power demands of complex multimedia and multi-network phones. Highly integrated chipsets such as next-generation Centrinos, the new TI devices and Broadcom's AirForce One processor for WLANs do increase efficiency of power consumption, but Neuvo believes battery advances are still sliding dangerously far behind the pace of change in others areas, notably the complexity of cellphone features.

Scaling of Cmos processes is enabling increasing integration and shrinkage of most aspects of the phone's electronics - including the baseband, memory and logic - but not the RF components, Neuvo argued. The problem worsens as phones need to support multiple radios. He claims the industry is reaching the point where the feature set of a high-end phone requires three watts of power while projected battery technology can deliver only two.

Power-hungry technologies

Already, typical phones are far more complex, incorporating components for camera, multimedia, GPS and so on. Reconfigurable logic and the truly digital radio architecture - enabling a multi-radio on one chip - help to address the complexity, but most of the available power is already being consumed by the demand for higher data rates. These in turn may depend on high speed and power-hungry RF technologies like gallium arsenide.

Although battery power has doubled over the past eight years, Neuvo admitted battery life will be the biggest drawback of Nokia's high end models, such as the forthcoming 7700, which consumers 3000mW of power.

Wireless Watch is published by Rethink Research, a London-based IT publishing and consulting firm. This weekly newsletter delivers in-depth analysis and market research of mobile and wireless for business. Subscription details are here.