Associate Editor
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The TNETW1250 chip from Texas Instruments supports 802.11 a, b, and g Wi-Fi standards. This lets designers of cell phones build in features like voice-overwireless LAN (VoWLAN), streaming media, and fast roaming between access points.
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The Clear Signal digital-radio receiver from Sonarics complete digital radio board. The modules digital radios to DVD boxes, or other consumer
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The Blackfin chips can be modified through software iteration without requiring hardware redesign.
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The buzz phrase heard around the electronics world is pervasive media. This refers partly to the growing phenomenon of the easy distribution of large quantities of digital content such as audio MP3 files and video on-the-go. Portable DVD players and personal video players let users download movies and watch them on the go.
Tying it all together is the advent of fast, reliable wireless networks. Integration of Wi-Fi into consumer devices is seen by some as a threshold event. Barriers to interfacing previously incompatible devices such as PCs and PDAs or cell phones and MP3 players are crumbling as the electronic chips that make communications possible get cheaper and faster. So data in the form of bytes of music, video, information such as weather, news reports, and even electronic advertising can be passed around and accessed more easily.
A chief incubator and source for technology underpinning pervasive media is the Massachusetts Institute of Technology Media Lab. The Lab's senior research scientist and director Andrew Lippman thinks consumer electronics is poised for a significant change defined by the pervasive media concept. Key to the change is the proliferation of wireless protocols and their integration into devices such as PDAs and other mobile devices. These devices will interact and communicate with others, forming a kind of web of wireless information.
THE ROLE OF SILICON
At the heart of this change is more powerful silicon. One example is the Blackfin processor family from Analog Devices, Norwood, Mass. The family is part of a new breed of embedded processors that meet the computational demands and power constraintsof embedded audio, video, and communications.Based on what's called Micro Signal Architecture-(MSA), developed jointly with Intel, the processors combine a 32-bit Risc-like instruction set with 16-bit dual multiply accumulate (MAC) signal processors. "Essentially, it is an instructionset architecture analogous to ARM, MIPS, or PowerPC," says Finbarr Moynihan, Blackfin product-line manager. Programming can be via assembly language or higher-level languages like C or C++.
In the past, custom chips like applicationspecific ICs, or ASICs, were programmed to do just one specific-task, such as to handle coding or decoding of audio or video data streams. Problem is, the costs of custom-made ASICs are rising so it's becoming cost prohibitive to offer more computing power in the tight margins of the consumer market.
Another feature of the family is the ability to precisely control power consumption. Dubbed Dynamic Power Management, or DPM, it adjusts the processing frequency and voltage depending on the application. For example, the core processor runs at 600 MHz and consumes 280 mW with memory and I/O shut-off. Video processing requires more muscle so the power consumption is doubled because the frequency is higher. Conversely, audio processing can take place at lower frequencies and power consumption drops to below the 280-mW mark.
Sonarics Labs of Kent, U.K., uses a Blackfin processor in its ClearSignal digital radio receiver. The digital-radio functions are integrated in software and include MP3 and WMA playback and recording on memory cards and CDs, as well as digital reception of legacy AM/FM broadcasts. It includes a digital-radio channel decoder and supports a number of broadcasting formats, including the European format for digital radio Eureka 147 DAB.
The digital receiver has a big advantage over earlier platforms. First-generation digital radios were built using a combination of separate ASICs: one for demodulating the broadcast signals, others for the MPEG audio decoder and for sound processing. An additional microcontroller chip performed the user-interface functions and coordinated the activities of the other chips. The Blackfin processor takes advantage of recent advances in DSP computational capabilities by implementing these dedicated circuits in software. Combining the functions on one chip saves board space and money. And at about $5/chip, this is low enough to fly in the cutthroat world of consumer products.
The ClearSignal radio is basically a digital-radio baseband on a general-purpose DSP. It also features a wide range of sound digital processing including bass and treble control, equalization, echo, reverb, and mixing, eliminating the need for dedicated circuitry. The system also includes a series of drivers and devices for connecting to the surrounding circuitry and hardware, including a/d, d/a, an IrDA port, as well as memory cards and CD devices.
SOFTWARE AND WIRELESS
On the software side, better compression schemes combined with faster and more flexible processors are letting designers add product features. Improvements in compression schemes such as MPEG4, H.263, H264, WM9, and others make it possible to transfer more content using less bandwidth.
Security is another big issue with wireless consumer products. OMAP (Open Multimedia Application Platform) processors and TCS cellular chipsets from Texas Instruments have built-in security features including accelerated encryption and decryption and authentication. And there's said to be ample processing power to let multiple digitalrights management (DRM) standards coexist without taxing the networks or mobile devices. These standards promise to protect the rights of content owners and ease security concerns they may have sending data over wireless networks.
All of this makes it so that virtually any service available today over the Internet can be delivered to cell phones and other mobile devices. TI's OMAP2 processors, introduced earlier this year, will let smart phones and other mobile devices incorporate Dolby-quality sound, interactive 3D gaming, DVDquality video, four-plus megapixel cameras, and digital camcorders and TVs.
TI is betting on the continued integration of wireless capabilities in consumer devices. It recently developed it's thirdgeneration 802.11 chip designed for mobile devices such as cell phones, smartphones, and PDAs. The two-chip package supports 802.11 b and g and combines a single-chip MAC/baseband processor with a radio-frequency front end and power-amplifier chip. This reduces board size by 50% compared with previous generations. The chips feature low-power standby modes and less than 400m A on standby. Industry watchers expect this to be the breakout year for the new technology as more Wi-Fi-enabled devices such as cell phones and PDAs hit the market. But ultimately, it'll be up to consumers to decide the winners and losers.
MAKE CONTACT
Analog Devices
(800) 262-5643
www.analog.com
MIT Media Lab
(617) 253-5960
www.media.mit.edu
Consumer Electronics Association
(703) 907-7600
www.ce.org
Sonarics
44 (0) 7774-168643
www.sonarics.com
Texas Instruments
(800) 336-5236
www.ti.com