THE FUTURE AS SEEN THROUGH TECHNOLOGY
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Qualcomm has a lot on its plate these days, providing the core silicon technology for 3G. But the CDMA innovator already has its eye on the next phase of wireless data. EV-DO Revision A networks haven't been launched yet, and it's already looking toward Revision B. The first commercial high-speed downlink packet access, or HSDPA, handset has yet to be shipped, but it's already planning to exceed the technology's impressive 14.4 Mb/s theoretical ceiling.
At the core of these developments is a new technology it calls multicarrier multilink eXtensions or MMX. Actually two technologies following the separate standards paths (HSDPA MMX and EV-DO MMX, respectively), the MMXes are not the next rungs on the standards' ladders. They are actually technologies optimized within the existing standards — Qualcomm's effort to ring every last bit of performance out of 3G before we move on to the elusive technologies of the fourth generation.
Qualcomm is essentially wrapping up a half-dozen new performance enhancement innovations into a single platform that will improve receive diversity, range and spectral efficiency, but the biggest features of MMX are its adoption of the multiple input/multiple output (MIMO) technology and the ability to access multiple channels over a single band of spectrum. MIMO is a multi-antenna technology usually associated with orthogonal frequency division multiplexing (OFDM) systems, but here Qualcomm is applying it to CDMA as a way to establish multiple airlinks simultaneously over separate frequencies and different transmission protocols.
The multicarrier aspect allows a device to access multiple channels of spectrum, increasing the overall capacity of the network. Combined, the two form a double punch, allowing not only capacity improvements of several orders of magnitude, but the ability to simultaneously access multiple networks for a single application.
“The fact today is we think about wireless in terms of one monolithic airlink versus another monolithic airlink,” said Jeff Belk, vice president of marketing for Qualcomm. “We want to use all of those airlinks concurrently, to pull together these disparate elements.”
For instance, a MediaFLO handset could access an OFDM signal in the 700 MHz band to receive a digital TV signal while simultaneously accessing the EV-DO network over 1900 MHz. Location-specific information could then be overlaid over the broadcast transmission. Another example would be using an HSDPA handset to receive both an assisted GPS signal and a data feed for real-time location-based services. There is no end to the amount of network technologies and applications that could be mixed and matched with the technology, Belk said.
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