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U. Glaeser

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TABLE 25.2<br />

Phone<br />

Modem<br />

Fax<br />

Web access<br />

Videophone<br />

Digital camera<br />

Palm-top<br />

DVD player<br />

DVR<br />

Set-top<br />

Digital TV<br />

Games<br />

MP3 player<br />

Home theater<br />

DAB<br />

MP3 Juke-box<br />

E-book<br />

PC<br />

Printer<br />

Car<br />

Speech coding is a traditional speech codec (compression/decompression) algorithm varying from 5<br />

to 12 kbit/s depending on standards, economic forces, and target quality. Above that, several speechquality<br />

enhancement features are added. This includes echo cancellation and noise suppression. A promising<br />

trend is the use of wideband codec. All together, the sum of all speech functions put in a modern<br />

cell phone can require up to 100 DSP MIPS.<br />

Channel coding is working on bits in transmission and (supposedly) in reception. As such, it does not<br />

qualify as a pure DSP application; however, in the first place, the reception is mainly done on samples<br />

and secondly equalization and other heavy DSP techniques (Viterbi algorithm) are classified under<br />

channel coding. Finally, the channel coding problems represent DSP research at its best today.<br />

Wireless Terminals<br />

The cell phone is the first of many types of wireless terminals that will come up over the next decade. In fact,<br />

wireless terminals are in a class of their own. Their rapid evolution differentiates them strongly from their<br />

wired cousins. Wireless is the technology with the most development potential over the next 10 years. It is<br />

easy to explain this statement by taking any existing equipment (from telephones to automobile) and turn<br />

it into a wireless device (Table 25.2). It is left to the reader to complete the table based on his or her own wishes.<br />

25.4 Consumer Products<br />

Section 25.3 proves that wireless will revolutionize many types of equipment. This is especially true for<br />

consumer devices. For instance, Bluetooth and GPS (both based on DSP) will be standard features on<br />

most consumer products described in the following subsections. In addition, consumer products have<br />

been traditionally nonconnected devices (camera, CD player) or passive devices (television). This is<br />

changing, in the form of access to the Web. This itself gives a big push to DSP applications.<br />

Digital Cameras (and Digital Pictures)<br />

One of the most promising consumer DSP applications is the field of digital pictures. Its most common<br />

incarnation is the digital camera. This very large field can be segmented in many ways, following these<br />

© 2002 by CRC Press LLC<br />

A List of Possible Wireless Devices<br />

Cellular<br />

Proximity<br />

(Bluetooth)<br />

Home RF<br />

(Residential)<br />

DECT<br />

(Cordless)<br />

Wireless<br />

LAN Broadband Satellite

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