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GSM handsets to integrate GPS

Posted: 01 Dec 2006 ?? ?Print Version ?Bookmark and Share

Keywords:GPS? GSM? handsets? mobile? wireless?

After years of anticipation, GPS is expected to emerge next year in a significant percentage of cellphones built to meet the GSM standard. Although government mandate and hunger for revenue are driving the trend, industry watchers say, only technological advancement makes it economically feasible.

In separate reports, analysts Satya Chillara of Pacific Growth Equities LLC and Alan Varghese of ABI Research touted the coming of GPS capability to handsets supporting GSM, the world's most widely used cellphone standard.

CDMA-based chipsets from Qualcomm Inc. have incorporated GPS technology since 2000, partly to comply with government security mandates such as E911, which requires wireless carriers in the United States to provide the location of emergency 911 callers to authorities, said Rob Rovetta, senior director of product management at Qualcomm. But GSM operators like Cingular Wireless and T-Mobile USA Inc. chose to deploy alternative technologies for E911 compliance, such as TruePosition Inc.'s Uplink Time Difference of Arrival (U-TDOA), which determines a caller's position by calculating the time it takes the handset's signal to reach operators' base stations.

Although TruePosition maintains that its technology fully complies with the more-stringent Phase II requirements of E911, many GSM carriers are deploying GPS technology, motivated in part by the desire to generate revenue from location-based services (LBS). A 2005 report from analyst Juniper Research predicts the total available market for mobile LBS will rise from $1 billion in 2005 to $8.5 billion by 2010.

"Finally, carriers think they can make some money with location-based services," Pacific Growth Equities' Chillara said.

But without the technological strides made in recent years, GPS would never be deployed outside of smart phones and PDAs, say industry executives.

"Over the last 10 years, the GPS industry has seen dramatic improvements in system architecture," said Blake Bullock, product manager of location solutions for Motorola Inc.'s mobile devices business. These include assisted GPS, a more-accurate incarnation that uses equipment at cell towers to triangulate a position. "That in and of itself has made for performance, cost and power improvements," Bullock said.

The form factor, cost and power consumption of GPS chipsets have also become more attractive through migration to more-advanced technology nodes, with GPS devices now commonly using 90nm process technology. GPS in wireless handsets has been further boosted by tighter integration into the system.

"The cost of putting GPS inside the phone was too high in the past," said Michel Windal, marketing director for operators, partnerships and open operating systems at NXP Semiconductors.

"Now that the operators are forced to incorporate GPS in the phones to comply with mandates, they are looking at how they can make money out of it."

There are varying degrees of integration of GPS in handsets. Qualcomm integrates its gpsOne technology directly into about 80 percent of its wireless chipsets, Rovetta said, to increase the technology's speed, accuracy and sensitivity; ease development; and reduce power consumption.

Direct onto silicon
At least one company has followed Qualcomm's lead by integrating GPS directly into silicon. Consumer application chip vendor Zoran Corp. markets what product-marketing manager Alon Shamir calls the only multimedia coprocessor to integrate GPS. In addition to other advanced multimedia features, Zoran's Approach 5C includes an embedded GPS baseband that supports both autonomous and assisted flavors of GPS.

Shamir said GPS processing is performed directly within Approach 5C. The application is completely encapsulated within the chip, he said, requiring no GPS software running on the phone's baseband chip, though the GPS application does require a second, inexpensive RF chip to serve as the GPS radio.

Improvements in system architectures enabled increase of GPS component revenues.

"We are using the same resources that are already available in our processor," Shamir said.

At the other end of the spectrum are standalone GPS chips offered by Sirf Technology Holdings Inc., considered the market leader in GPS chipsets for consumer applications, as well as Texas Instruments Inc. (TI) and specialty vendors like Global Locate and GloNav. While standalone devices don't offer the integration advantages of Qualcomm's CDMA products, they do represent the path of least resistance for customers looking to hit tight market windows, say proponents.

Kanwar Chadha, Sirf founder and VP of marketing, said his company's chipsets, traditionally strong in personal and in-car navigation systems, have found their way into more handsets partly because of shrinking form factors and lower power consumption based on the migration to 90nm process technology and use of more sophisticated algorithms.

Sirf also got a boost in technology and customer base when it acquired Motorola's GPS division last year. Chadha said Sirf's technology is integrated into handsets in multiple ways: as standalone chipsets, directly into silicon through licensing arrangements, and through intermediate integration. In that last approach, a system is configured so that the GPS chip shares gates with other components, enabling filter and memory sharing.

Most insiders agree that GPS functionality will be widely integrated directly into silicon as uptake increases. NXP's Windal, whose responsibilities include evaluating GPS technology for incorporation into NXP cellular platforms, said he believes GPS capability will be available in about 30 percent of all handsets within six years.

"In this kind of volume, it makes sense to integrate the GPS function into the phone's baseband," he said. "In the short term, there are probably people that will put it on the coprocessor. But in the long term, it will migrate to the baseband."

Stephan Bork, GPS business manager at TI, which offers a single-chip assisted-GPS solution, GPS5300 NaviLink 4.0, said the company continues to study integration of GPS into its other wireless chipsets and will consider it when GPS uptake reaches an appropriate level.

"Eventually, integration is something that can happen," Bork said. "We have the capability to do that any time."

Integration expense
Zoran's Shamir agreed that GPS on the multimedia coprocessor is not likely to be the long-term solution. In about five years, he said, assuming GPS uptake meets projections, GPS functionality will likely migrate to the phone's baseband, as will all multimedia functions that become popular enough to justify the integration expense. "All of the features that become popular eventually migrate to the baseband," he said. "We need to be ahead of the baseband in integrating functionality because the baseband development cycles are very long and costly."

Analyst Will Strauss, president of Forward Concepts, said the time will come "when the volumes kind of force integration to happen."

But Sirf's Chadha argued that silicon integration isn't uniformly the right solution, noting that with the technology constantly evolving, integrating everything into one platform could have drawbacks.

"Do you want to respin the whole wireless chipset?" Chadha asked. "I think you are going to see a combination. GPS is not 10,000 gates that you can just integrate. It's a pretty sophisticated technology."

- Dylan McGrath
EE Times

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