Communications Fundamentals

Chapter 6: MODULATION

In this chapter, we return to the core stages of the digital communications system by examining modulation. Whereas cryptography transforms information for security, modulation transforms digital symbols into physical waveforms suitable for transmission over real channels. Understanding this transformation is essential, because the performance limits of modulation, noise, bandwidth, and signal power ultimately constrain the secure transmission of encrypted data.

Chapter Contents

• 6.1 INTRODUCTION
• 6.2 ANALOG MODULATION
• 6.3 AMPLITUDE MODULATION
• 6.4 FREQUENCY MODULATION
• 6.5 SUMMARY OF ANALOG MODULATION TECHNIQUES
• 6.6 DIGITAL MODULATION
• 6.7 PSK
• 6.8 LOOKING AHEAD
• 6.9 REVISION QUESTIONS
• 6.10 FREQUENTLY ASKED QUESTIONS