Embedded system engineering magazine 2005.10

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phones and MP3 players now that low power products are becoming available. Toumaz Technology’s newly formed joint venture, Future Waves Pte Ltd., has developed its first product for DAB based on Toumaz’s proprietary ultra-low power silicon technology platform. Taiwanbased Future Waves, an RF CMOS fabless design house, is licensing Toumaz’s core AMx advanced mixed signal and RF technologies to develop digital broadcasting receiver applications within the Far East market.

Future Waves will make functional samples of its first DAB RF tuner chip – FENIX – available to selected customers from mid Q3 2005. The FENIX (FNX14701) highly integrated single chip RF solution for DAB and FM offers the lowest power consumption and cost, combined with the highest functionality, available in the industry today, paving the way for widespread adoption of DAB receivers in portable and handheld equipment, such as next-generation mobile phones and PDAs.

The older relative, AM technology has, surprisingly enough, digital potential and as defined

Technologies

DRM

DRM is a non-proprietary digital radio system for short, medium and long-wave transmissions. It has been endorsed by the ITU, IEC and ETSI. While DTM currently covers broadcasting bands below 30 MHz, the DRM consortium voted in March 2005 to begin the process of extending the range to 120 MHz

SBR

Spectral Band Replication (SBR) is a new audio coding enhancement tool which is standardised in ISO/IEC 14496-3:2001/Amd.1:2003. It has the ability to improve the performance of low bit rate audio and speech codecs by either increasing the audio bandwidth at a given bit rate or by improving coding efficiency at a given quality level. It can increase the limited audio bandwidth that a conventional perceptual codec offers at low bit rates, so that it equals or exceeds analogue FM audio band-

in the Digital Radio Mondiale (DRM) specification. This can be applied to Shortwave, Medium and Longwave transmissions. There is potential for manufacturers to include DRM in new DAB radios to provide extended coverage and additional services.

Coding Technologies provides a number of products that support the design and implementation of DRM systems. These include audio encoders and decoders for Linux and Windows PCs. These support aacPlus, CELP+SBR and HVXC+SBR. They also provide decoder software libraries for TI TMS320C55 DSPs. They also supply a DRM decoder DSP board based on a Philips TriMedia 1300DSP, bundled with complete DRM audio coding, channel coding and modulation modes.

Digital Radio Mondiale

On the heels of their June announcement of the availability of chips and modules for the DRM standard, a number of companies attending IFA

width (15KHz). SBR can also improve the performance of narrow-band speech codecs, offering the broadcaster speech-only channels with 12KHz audio bandwidth, used for example in multi-lingual broadcasting. By adding SBR to MPEG Layer-2, the bit-rate of a particular audio source can be reduced by up to 50%, while maintaining the audio quality.

MPEG-4aacPlus

This is a combination of three MPEG technologies, comprising Advanced Audio Coding (AAC), coupled with Coding Technologies’ SBR and Parametric Stereo.

Although often limited in content and time span, there are currently quite a few DRM transmissions being made around the world. Most of these are in Europe but, for example, even in the Hunan province of China there is a 24 hour economic program. See - drm.org/livebroadcast/livebroadcast.php

in Berlin demonstrated product prototypes developed around TI’s DRM350 digital baseband and RadioScape’s RS500 module. This release of products will accelerate DRM’s rollout and TI and RadioScape will enable products from consumer brands to appear on store shelves within the year – www.ti.com/drmsolution). Among those unveiling designs at IFA were Morphy Richards (www.morphyrichards.co.uk), Roberts Radio (www.robertsradio.co.uk) and Sangean (www.sangean.nl ).

TI’s DRM350 enables developers to create cost-effective dual DRM/DAB-based devices with a single chip and to easily implement enhanced features on the integrated programmable DSP, such as digital content playback of MP3 and Windows Media Audio (WMA) files. RadioScape’s RS500 module, a complete DRM solution, is based on TI’s DRM350 and includes all of the hardware and software necessary to support any combination of DRM, DAB, FM-

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agement for music downloads; software programmable, allowing enhancements, such as EPG, to be added as software upgrades, either at the factory or in the field; and low-power, enabling radio on the go with a battery life similar to that of portable digital audio players.

RISC and DSP

All this can be catered for by a flexible and programmable solution that combines RISC and DSP functionality. Such a platform solution can form the basis of a complete family of digital radio products supporting different standards, feature sets and price points, reducing overall development costs.

The leading standard for Europe, Asia and Canada is DAB (Digital Audio Broadcasting). DAB has also been adapted in Korea to form the basis of their mobile digital TV standard, T-DMB. In most territories it will be necessary to support more than one digital radio standard in each

the high power consumption typical of other solutions. The programmable META allows enhancements to be added as software updates, making it more flexible than fixed hardware solutions and removes the need for multicore solutions.

SDR platform

That is where the second IP block comes in. UCC Mobile is a programmable Software Defined Radio (SDR) platform designed for use in high performance multi-standard data receivers. UCC Mobile is a derivative of the UCC designed to target mobile applications, where battery life is key. It is configurable and programmable to accommodate a range of world-wide digital radio standards including DAB/T-DMB, DRM, HD-Radio, XM and ISDB-Tss, allowing the development of multi-standard digital ‘world-radios’ and an SoC product line based on the same core technology, leveraging software investment.

run simultaneously on a DVB-T solution using this IP.

DRP is entirely software programmable, and allows field upgrades of functionality, such as EPG, even by end users.

META works at 32 bit fixed point for more accuracy in linear filter coefficients and a 32bit word length gives greater dynamic range. Whatever users invest in META software development can be leveraged again later for other META devices – same software dev tools etc. Keeping all of the DRP development in house rather than using external suppliers has ensured that development remains closely integrated between hardware and software and performance and time to market aggressively maintained. The platform is available as soft IP that can be integrated into a new or existing SoC design. <Ends>

www.imgtec.com

Time to market

The reason for this—as almost invariably in business--centres on money and time-to-market. Network processor software is all about money and accelerating product deliveries.

The fewer lines of software code an equipment maker has to write for the network processor chosen, the less time and money they have to spend developing their products. The less time they have to spend writing code, the faster they can accelerate their product time-to-market schedules, and the faster they can start generating revenues for their equipment.

Furthermore, because they can spend less time writing software code, they can spend more time developing unique, revenue-generat- ing features for their equipment.

Reliability

Reliability of their equipment also plays a part in the importance of software. The fewer the

Equipment manufacturers can’t afford to buy fixed function chips for current equipment and then buy a whole new set for their nextgeneration equipment. Instead they need a single platform that can be used for many years into the future. This means they need programmable network processors. The way network processors are programmed is by using software code. The fewer the lines of software code, the more reusable it is. The easier it is to modify that code for future equipment, protocols, and technologies, the more valuable it is to manufacturers.

“For most people working in the network processor market, the most difficult part to understand is the software,” according to Eric Mantion, senior analyst with In-Stat who recently published a new report on network processors and related software. “The problem is that, no matter how good an NPU is, without well written software, it is worthless.” This small nuance makes software a critical part of any network

are precious few places in the world where one can learn how to programme a network processor.”

Mantion suggested that what you might see in the near future are two software teams. One will focus on making software code for prototypes to be shown in trade shows and product demos. The other team would take the quick code generated by the first group and optimise it to the peak of efficiency, ensuring it is both fast and durable.

“While no one likes the inconvenience of his or her computer freezing, having the same thing happen in a Terabit router equipped with a network processor can be disastrous. Financially, these things often have multi-million dollar Service Level Agreements that can cost millions of dollars an hour after as little as five minutes