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U. Glaeser

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Classifying DSP Applications<br />

It is usually to classify DSP applications following the market segments. For the purpose of this chapter,<br />

we conveniently classify the seven main areas of DSP applications without necessarily following the market<br />

segments of Fig. 25.1:<br />

1. Military<br />

2. Telecommunication terminals<br />

3. Consumer products<br />

4. Telecommunication infrastructure (including networking)<br />

5. Computers, peripherals, and office automation<br />

6. Automotive, industrial<br />

7. Others, such as biometrics, biomedical, etc.<br />

25.2 Military Applications<br />

The first DSP applications were born in the 70s and were mainly military (radar, sonar). Today, the same<br />

applications exist with a much higher performance target. In addition, many military applications<br />

(vocoder) are taking advantage of “civilian” work. An interesting development for the military is the<br />

detection and disposal of mines [1]. It must be noted that, since the military community was the first<br />

DSP customer, strong links were created between DSP manufacturers and these pioneers. Despite its<br />

small size, the military community continues today to have a strong influence on the evolution of DSP<br />

architecture (floating-point, multiprocessing).<br />

25.3 Telecommunication Terminals<br />

By 1995, DSP has left its original circles (military, universities) and became a household name. The<br />

most popular DSP applications were telecommunications terminals such as cellular telephone, PC<br />

(modem), fax, and digital-answering machine (Table 25.1). Today, the quantity of telecom terminals<br />

that is produced per year reaches 450 M units for cell phones alone.<br />

Phones and Answering Machines<br />

The plain old residential telephone has very little DSP inside it (maybe calling ID). This is the exception<br />

among voice communication devices. For instance, second generation cordless phones (DECT) use digital<br />

techniques. Also all “packet telephones” such as Internet (IP) phones, LAN phones, are using voice<br />

compression, echo cancellation, and modem techniques to receive/transmit voice. An extreme telephone<br />

application can cater for up to 12 voice conference channels. This requires 12 decompression channels<br />

and mixing. Voice compression is not new, since they allowed the development of cheap “solid-state”<br />

DAM (digital answering machines). All put together, a combo device including a multi-channel cordless +<br />

a DAM + a connection to IP is a very demanding DSP application.<br />

TABLE 25.1<br />

© 2002 by CRC Press LLC<br />

List of Telecom Terminals Using DSP Techniques<br />

Communication Function List of Terminals<br />

Voice (telephony) Feature phone, DAM, cordless phone, Internet phone, business phone,<br />

LAN phone, DECT phone, combo products (LAN/POTS)<br />

PC modem (Voiceband) modem, DSL modem, cable modem<br />

Fax Color fax, fax/phone, fax/printer, fax/printer/scanner/copier<br />

Web access Web station, Web phone, Web pad<br />

Videophony Videophone<br />

Cellular phone Standard, voice + data cellular phone, smart phone, pager

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