Everyone knows of the basic cellphone that has the "killer ap" of voice. But even if that's all one uses it for, the elemental cellphone is giving way to perhaps 100 new cellphone designs a year, many of which are called "smartphones." But, what's really a smartphone?
There is no accepted industry definition. For one company, a smartphone is (at least by implication) a cellphone with PDA capabilities; in another it's a PDA with cellphone capabilities. Some insist it's any cellphone with data capabilities. Others insist that a color screen is necessary for the moniker to apply. And everybody agrees that if it has a camera, it must be a smartphone. And yet others insist that it has to be a cellphone with secondary wireless capabilities like Bluetooth, GPS and/or 802.11b. And others would ascribe the label only to cellphones with a separate application processor chip for multimedia functions. Some cellphone companies, not wanting to be pinned down, simply have a "family" of cellphones, some units with more of these features than others.
As market researchers, we are often asked, "How big is the smartphone market?" Unfortunately, if we group all of the products mentioned above into a single category, the information is virtually useless to anyone involved in product planning. That is, if a smartphone doesn't have to have a camera to deserve the label, how can we gage the number of the cameras if we group all of them into a single category? But, some public relations person will insist that their client's product addresses the $xx billion smartphone market. That becomes a big "gee-whiz" number that gets attention, but conveys little information about the true market served by that product.
So, what does all of this have to do with digital signal processing technology? Cellphones are the biggest single market for DSP silicon, so it is important that we understand the extent that DSP technology pervades that market. Digital signal processing is the underlying technology for all digital cellphones, originally as the cellular baseband modem, but now expanding into additional functionality, with so-called "multimedia."
Multimedia is the human perception of DSP functionality related to audio and video. First implemented as an MP3 player on cellphones, multimedia has expanded into digital still camera capability and even video capture and playback.
This advanced multimedia functionality requires considerable DSP power, and not wanting to disturb the DSP baseband that took months to qualify in each global region, a second chipthe application processorhas emerged. And we have to count that additional instance of DSP functionality. Does this constitute a smartphone? What about the ones that only have ringtones and MP3 player capability? Are they dumb phones?
DSP is also necessary for GPS reception and basebands for Bluetooth and 802.11x. We are first seeing these as separate chips in the cellphone, but as geometries shrink over time, everything except the RF circuits will be sucked unto the single cellphone baseband dieeither as separate DSP "engines" or as one or more dynamically reconfigurable DSP elements. Exactly how this will evolve is unclear, but it is clear that the term "smartphone" will be a continually moving target.
About the Author:
Will Strauss is the President of Forward Concepts (www.fwdconcepts.com), and is considered an authority on markets driven by DSP technology.