Television by way of personal computers (PCTV) is the TV industry's Rodney Dangerfield; it just gets no respect. In January, Junko Yoshida wrote on www.wirelessnetdesignline.com that adding a broadcast TV receiver to portable gadgets seems superfluous when young people watch what they want, when they want via the Internet.
While the laptop seems like a natural fit for mobile TV, PCTV has been the industry stepchild. One reason is mobile phone TV's reigning position as media darling, sucking up all the air in the room for other mobile devices. A second reason is the limitations of last-generation technology: Bulky external tuners and antennas simply use too much power.
For example, one PC mobile TV solution introduced last year has, in addition to a TV tuner card, six components, two software CDs and a user manual. If broadcast TV made similar demands on early viewers, we'd still be listening to “The Ipana Troubadours” on the crystal set.
But the past two years witnessed a virtuous circle unfolding with the potential to rouse PCTV from its market inertia.
The third screen
First, the availability of live Olympics coverage on mobile TV services introduced many people to the third screen. Second, the ultra-portable and ultra-cheap Netbook equipped folks with another always-with-you device — one featuring a bigger screen than a phone.
“The use model has completely changed,” says Telegent Systems PCTV product manager Sanjay Noronha. “The form factor is so intuitive, light and small that people take them along all the time.”
The right technology to perfect this alchemy started falling into place last year with a critical mass of suppliers launching new low-power, sub-$5 TV tuner chips, enhancing existing tuners for new markets, and (most important of all) signing OEM deals that will build the tuners into new laptops and Netbooks in the same way as Wi-Fi cards and DVD players.
In 2008, Telegent introduced the TLG2300 chip, which integrates everything — demodulator; decoder; DSP; stereo FM radio; high-speed USB peripheral; and a DVB-T, PAL, SECAM and NTSC tuner — into a standard 10mm chip. This design offers a large reduction in board space and cuts power requirements 75 percent, according to Noronha.
“You can watch TV on a Netbook for about three hours before draining the battery,” Noronha says.
Antennas are another challenge for PCTV, Noronha says.
“Without a receiver that's very, very sensitive, it's been hard to integrate TV into the laptop, so you had to carry around an antenna,” Noronha says. “We engineered the solution for very high sensitivity to enable the adoption of internal antennas. We have direct conversion architecture, and our DSP algorithms greatly increase sensitivity and mobility.”
Last June, Telegent joined forces with Topstar Digital Technologies to deliver TV-enabled Netbooks and PCs that receive both free-to-air terrestrial analog TV and digital (DVB-T) signals. Both PC and Netbook designs will be available in mass production later this year. Recently unveiled at Computex in Taiwan, Topstar's 18in all-in-one PC was designed from the ground up for hybrid TV, with the entire system optimized for TV performance.
Software demodulation
Another 2008 entry into the PCTV arena is Mirics Semiconductor, which signed its first OEM deal for its FlexiTV multistandard receiver chip and configurable software demodulator. (See Figure 1.) A host processor-based software system originally targeting dual-core x86 notebooks, FlexiTV is ideal for ultraportables such as Netbooks and mobile Internet devices (MIDs), where maintaining battery life is critical. For example, with ISDB-T 1-Seg, software demodulation running on an N270 Atom processor consumes a CPU load of only 20 percent.
“With a purely hardware solution you have to spin new silicon,” says Chet Babla, Mirics product line director. “All we have to do is redevelop the algorithm. You give new software to OEMs, and instantly their product lines are upgraded. With hardware, you're looking at six to nine months.”
But software demodulation “isn't easy to do and do efficiently,” Babla admits. “You don't want to max out the CPU. We had software and algorithmic expertise within the company — a novel combination of skills.”
Mirics leverages DSP-like instruction sets available on the processor platform to ensure that the demodulation is efficient. Since then, Mirics has extended FlexiTV to support China's DTTB standard, Japan's ISDB-T (1-Seg), and the Intel Atom CPU and ARM-based platforms. The aim is encouraging both embedded and add-on mobile TV and radio functionality for ultra-portable and low-power Netbooks and MIDs. The strategy appears to have worked. In September, Mirics signed agreements with PCTV accessory makers Quincy Digital of Korea and Skycast of Brazil.
Multistandard receivers
PCTV got another boost this year from graphics processor company NVIDIA and PC accessory maker Hauppage Computer Works. NVIDIA chose Siano Mobile Silicon's SMS1150 mobile TV receiver chip to provide PCTV on its next-generation Tegra Netbook. The multistandard receiver enables both SD and HD mobile TV, and supports DVB-T, ISDB-T, DVB-H, DAB, T-DMB and CMMB standards — opening up potential market opportunities nearly everywhere in the world except North America.
Hauppauge partnered with MaxLinear to build an embedded PCTV module for the North American (ATSC) market. This is the third generation of MaxLinear's configurable MxL5007T chip, which supports terrestrial TV standards, including ATSC, DVB-T, DVB-H and DTMB.
“The fully configurable architecture means, from an inventory management perspective, you only have one part number, and you configure it depending on where you're shipping to,” says Stefan Szasz, MaxLinear director of marketing.
Even simpler for OEMs is Cresta-Tech's multistandard CrestaTV software PCTV tuner, which supports all standards and decides on the fly which one to use. (See Figure 2.)
“OEMs want to build one product for the mass market, not one product for every different market,” says Ramon Cazares, CrestaTech marketing and sales vice president.
CrestaTV has its roots in founder George Haber's tech DNA. Haber's guiding axiom is: “If it can be done in software, it will.” Almost 20 years ago, when multimedia chipmakers were focused on dedicated video decoder chips, Haber founded CompCore Multimedia and developed the first software video decoder using the CPU's processing power.
CrestaTV scans the entire TV spectrum for analog, digital and cable-in-the-clear signals, Cazares explains. However, the integrated GPS enables a directed, intelligent scan.
“The tuner knows where you are and what channels you should be able to receive,” he says. “This directed scan takes three seconds as opposed to 20 or 30 minutes.”
This is where the software beats hardware, according to Cazares. In silicon, you need to minimize the number of registers and the amount of memory. Otherwise die size explodes.
“If you do it in software,” he explains, “you can make the registers as big as you need — there's no cost penalty — and turn specific algorithms on or off by region.”
In order to minimize CPU load, CrestaTV uses a dual antenna system with two tuners.
“We take the output of one tuner and loop it back to the other tuner, and send the optimal signal to the CPU for demodulation,” Cazares explains. “Our benchmark is to be 50 percent of the [CPU] load or less — similar to a DVD.”
Power use is likewise comparable to a DVD player, he adds.
While these solutions have yet to appear on retailer shelves, Noronha sees a big opportunity when they do — possibly later this year.
“With Netbooks, a huge adoption of these devices is in emerging markets,” he says. “Consumers, who previously didn't have access to computers, now have access because of the low price. TV is ubiquitous — it needs no introduction. And in the developing world, TV is the main conduit for information. And, this feature has received tremendous interest from focus groups by tier one manufacturers. People have been screaming about this feature, not a fingerprint sensor.”
Carolyn Schuk is editor of Broadcast Engineering Mobile TV Update.
