RadioScape picks Blackfin for mobile TV platform

As mobile TV opportunities shift to Asia, technology suppliers are teaming with new, sometimes surprising, partners to formulate strategies.

RadioScape plc, a London-based software developer for Digital Audio Broadcasting (DAB) systems that tapped a DSP from Texas Instruments Inc. for digital radio, announced in March that it has chosen Analog Devices Inc.'s Blackfin processor as its mobile TV platform. RadioScape will share its extensive "end-to-end" DAB knowledge with ADI to build mobile TV receivers based on the Eureka 147 DAB standard, according to RadioScape.

When asked why RadioScape had switched to ADI for its mobile TV play, CEO John Hall, said, "We are a software-defined radio company. We simply pick the best platform for a specific market. We have no ax to grind in terms of which chip to use." TI will remain RadioScape's partner for the digital radio market, he said.

For ADI, the deal caps a series of mobile-TV moves over the last 12 months. Those actions included the acquisition last year of South Korea-based Integrant Technologies Inc., which develops high-performance, low-power radio tuners for mobile communications, computer and consumer devices to receive DTV and digital radio broadcasts.

The RadioScape announcement coincides with ADI's rollout of its latest Blackfin processors for portable media players (PMPs), mobile TV and other mobile applications. The ADSP-BF52x features the company's Lockbox security technology and boasts what ADI says is the Blackfin brand's best power efficiency to date.

Under the partnership with ADI, RadioScape will provide baseband decoder software including DAB audio, DAB data, T-DMB and DAB-IP, in addition to audio and video decoders (H.264 video and MPEG-4 for both AAC+ and BSAC audio). RadioScape offers all the components "as a single software framework," said Hall. "We glue everything together."

RadioScape provides baseband decoder software, including DAB audio, DAB data, T-DMB and DAB-IP, plus the A/V decoders to run on Blackfin. (Click to view full image)

Painless process
"We are taking the ADSP-BF52x to RadioScape, and they are doing all of the hard work in terms of putting their software on the system," said Tony Zarola, product line manager for mobile products at ADI. Despite the technical challenges involved in integrating the RadioScape software onto Blackfin, the process was relatively painless and fast, Zarola said. "I am tempted to say that it took six months to get from zero to the grand platform."

System vendors in South Korea and China are coming to realize that just acquiring DAB stacks, writing A/V codecs and running them on a DSP results in mobile handsets that cost too much, Hall said. "You need a middleware layer, or a good framework that can connect them together. We offer good DSP encoding and programming expertise."

Hall said ADI had approached RadioScape last October to tap RadioScape's software expertise. Thus far, the companies have demonstrated the full, 544Kbps T-DMB data rate on a Blackfin BF533 doing both the baseband and A/V decode, according to RadioScape.

According to ADI, the ADSP-BF52x lets designers make trade-offs and optimize for power and performance. The processors are available in a range of incarnations, from a 600MHz high-performance device to a 400MHz ultralow-power part, and are priced at $5.50 to $14.50 per unit in 10,000-unit quantities.

The new Blackfins implement internal voltage regulator and process improvements to enhance dynamic power management, with power consumption scalable on-chip to match the MIPS necessary for the function being executed.

Meanwhile, the parts' Lockbox secure technology—a combination of hardware and software mechanisms that has been incorporated in other Blackfin processors as well—can implement security measures ranging from identity verification to intellectual property (IP) safeguards and digital-rights management.

As PMPs and other devices proliferate, "there is so much data flying about that it's impossible to keep track of whether the IP is protected," Zarola said. "Lockbox is a scheme we have developed with Blackfin to enable customers to store private keys."

Running mobile TV demodulation and A/V decoding in one chip, as the Blackfin does, is a marked departure from the conventional coding schemes used in handsets and PMPs. Traditional mobile TV receivers comprise a DTV tuner IC and a demodulation chip, with A/V decode carried out in a separate multimedia processor in a handset. While DVB-H chip vendors have been looking to integrate the DVB-H tuner and demodulator, the assumption has been that A/V decode would continue to reside in a separate multimedia chip or coprocessor. Many high-end handsets already contain such chips for camera or MP3 player functions.

'Lowest possible cost'
For so-called feature phones and PMPs, however, "getting the cost out of the design is most important," Hall said. Noting that ADI's DSP can eliminate the expensive application processor, he said, "We can offer mobile TV at the lowest possible cost." Hall also noted that the integration of RF and baseband for mobile TV has proved more difficult than anticipated. "Some companies are back to the drawing board on this topic," he said.

Speculation was rampant at the last 3GSM World Congress that TI's ballyhooed Hollywood single-chip DVB-H tuner and demodulator had failed to garner an expected design win from Nokia. The handset giant was said to be using its own DVB-H chips in its newly announced mobile TV handsets.

Tifany Wilson, business development manager for mobile DTV solutions at TI, said the Hollywood chip has secured multiple handset design wins, but TI is not at liberty to reveal those customers.

Wilson said Hollywood was first sampled to Nokia and others in 2005. Nokia, she said, asked for some modifications "based on what they saw in the market." That's not atypical, she said. "When you take a chip to a handset vendor, they are always going to ask for changes."

She did acknowledge, however, that uptake for the Hollywood chip has been slower than expected. She blamed it on the sluggish rollout of mobile TV itself.

While stressing that he had no specific knowledge of who is supplying the chips for Nokia's newest mobile TV phones, RadioScape's Hall acknowledged that higher mobile TV volumes overall might hasten the chip industry's ability to solve its RF and baseband integration issues. "If mobile TV were a 100 million-unit-per-year market, the industry would have already fixed this problem," he said.

RadioScape will offer a turnkey DAB-based receiver combining the Blackfin with either an Integrant-developed ADI tuner or RadioScape's own tuner, said Hall. "We have not decided yet."

- Junko Yoshida and Dylan McGrath
EE Times