With close to 1.18 billion mobile handsets sold in 2007 and an expected 1.8 billion in 2012, the attach rate metrics for GPS technology in cell phones are becoming increasingly important for both industries.
Bluetooth and FM radio technologies have the highest attach rates in today's cell phones, with GPS technology following closely. As attach rates grow and these radios increasingly are embedded in the same system, the technical and cost-structure benefit opportunities build a strong case for integration.
As the technologies approach 100% attach rates and major equipment manufacturers move forward with plans for aggressive propagation, it becomes increasingly viable for these three radios to be integrated into cellular basebands.
The key merits of integration include reduced silicon area due to shared components in the device, reduced external bill of material (eBOM) costs, improved system performance due to tightly integrated algorithm implementations, improved cost structure due to economies of scale of single silicon systems, and shared packaging that leads to ease of assembly.
Technology costs
The semiconductor industry thrives on Moore's Law - the concept that technology becomes exponentially smaller, faster ,and more cost-efficient every two years - making integration a logical trend in connectivity technologies for mobile handsets. Current connectivity integration trends show horizontal integration of technologies like Bluetooth, GPS and Wi-Fi, while the same technologies integrate vertically into the cellular baseband device.
The later trend is typical of technologies that are more mature and have attach rates upwards of 80%. If the attach rates are not high enough, there is a risk of unused silicon on the device, yielding unnecessary costs for equipment manufacturers and consumers.
Case for integration
Several functions on a device can be leveraged across the GPS, Bluetooth, and FM radio technology functions. This integration can deliver a solution that is cost- and size-optimized over a discrete implementation, but at the same time delivers state-of-the-art GPS performance in a cellular handset as a discrete GPS-only device.
There are many key benefits from integration of any two (or more) technologies in a cellular handset:
Complete solution cost
- eBOM savings due to integration
- System savings from sharing interfaces and connectivity
- Easier board layout due to clocking and power management sharing at the phone-level
- Solution size
- Ability to supply a unified firmware package and host software solution that is pre-tested and integrated
- Shortening the test time with easier test setup
- Power consumption savings from sharing functions on a single die
- System level co-existence performance
- Enhancements due to mechanisms built into the device to facilitate co-Existence performance at a phone level for the three technologies.
By integrating Bluetooth, GPS, and FM functions in a handset, a semiconductor and systems company can leverage its broad technology portfolio to provide solutions that drive down the cost of adding these functions into a handset. This cost optimization results in an overall cost savings for the mobile handsets and drives higher attach rates into an increasingly lower tier of cellular handsets, making the technology available for mainstream consumption.
Yatin Acharya is worldwide GPS hardware and systems product manager at Texas Instruments
Amir Faintuch is director of business marketing and product marketing, mobile connectivity solutions, at Texas Instruments
This article originally appeared in GPS World