Question 4 a. AM modulation is inefficient. With reference to the frequency domain, explain why. How does double sideband and single sideband suppressed carrier modulation improve the efficiency of AM modulation? Despite its increased efficiency, what is a disadvantage of SSB-SC when compared with AM modulation. b. An antenna has an impedance of 75 Q. An unmodulated AM signal produces a current of 3.4A. The modulation is 90 percent. Calculate (a) the carrier power, (b) the total power, and (c) the sideband power. c. With aid of diagrams, explain how frequency modulation works.

Question 4 a. AM modulation is inefficient. With reference to the frequency domain, explain why. How does double sideband and single sideband suppressed carrier modulation improve the efficiency of AM modulation? Despite its increased efficiency, what is a disadvantage of SSB-SC when compared with AM modulation. b. An antenna has an impedance of 75 Q. An unmodulated AM signal produces a current of 3.4A. The modulation is 90 percent. Calculate (a) the carrier power, (b) the total power, and (c) the sideband power. c. With aid of diagrams, explain how frequency modulation works.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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