Overview - Digital Design of Signal Processing Systems: A Practical Approach - page 1

1
Overview
No exponential is forever ... but we can delay “forever”
Gordon Moore
1.1 Introduction
This chapter begins from the assertion that the advent of VLSI (very large scale integration) has
enabled solutions to intractable engineering problems. Gordon Moore predicted in 1965 the rate of
development of VLSI technology, and the industry has indeed been developing newer technologies
riding on his predicted curve. This rapid advancement has led to new dimensions in the core subject
of VLSI. The capability to place billions of transistors in a small silicon area has tested the creativity
of engineers and scientists around the world. The subject of digital design for signal processing
systems embraces these new challenges. VLSI has revolutionized the commercial market, with
products regularly appearing with increasing computational power, improved battery life and
reduced physical size.
This chapter discusses several applications. The focus of the topic is on applications primarily in
areas of signal processing, multimedia, digital communication, computer networks and data
security. Some of the applications are shown in Figure 1.1.
Multimedia applications have had a dramatic impact on our lives. Multimedia access on handheld
devices such as mobile phones and digital cameras is a direct consequence of this technology.
Another area of application is high-data-rate communication systems. These systems have
enormous real-time computational requirements. A modern mobile phone, for example, executes
several complex algorithms, including speech compression and decompression, forward error-
correction encoding and decoding, highly complex modulation and demodulation schemes, up-
conversion and down-conversion of modulated and received signals, and so on. If these are
implemented in software, the amount of real-time computation may require the power of a
supercomputer. Advancement in VLSI technology has made it possible to conveniently accomplish
the required computations in a hand-held device. We are alsowitnessing the dawn of new trends like
wearable computing, owing much to this technology.