EEE206_2003_Solutions

# EEE206_2003_Solutions - Solutions to EEE206 Spring Semester...

This preview shows pages 1–2. Sign up to view the full content.

Solutions to EEE206, Spring Semester 2003 1. (a) Improvement in signal to noise ratio Ease of radiation in radio systems, since efficient radiation from an antenna requires its length to be λ /4 Use different carrier frequencies to separate signals with similar baseband frequencies Facilitates multiplexing (b) For AM, m = E m / E c m should be kept less than 1 to avoid 'splatter' in output spectrum (c) (i)Total power = P c (1+m 2 /2) = 5 x 10 3 when m = 1 Hence carrier power = 3.33 x 10 3 watts (ii) m = 0.85 Power in one sideband = m 2 P c /4 = 0.85 x 0.85 x 0.25 x 3.33 x 10 3 = 601.5 watts if P RC = power in reduced carrier, 10 log 10 (P c / P RC ) = 25, hence P RC = 10.5 watts Total output power = 10.5 + 602 = 612 watts (d) m 1 = 0.7, m 2 = 0.5 and m 3 = 0.2 Composite m = (0.7 2 + 0.5 2 + 0.2 2 ) = 0.883 Total power output = 3.33 x 10 3 (1 + .883 2 / 2) = 4.633 x 10 3 watts 2 (a) Diagram should show a single superhet circuit with RF amp, mixer, LO, IF amp, demodulator, AF amp and LS. The demodulation process should be explained with the aid of a spectrum plot of the FM modulated carrier for both mono and stereo signals.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern