q1_03

# q1_03 - Use Huffman coding to find the binary codes. What...

This preview shows pages 1–4. Sign up to view the full content.

EE455 Quiz1 2/25/2003, 3:15-4:30 (Close book, 1 page formula sheet allowed) Put and hand in answers on quiz . You may use back pages Name: ID# . Each bullet is 5 points unless stated otherwise. Problem 1 Who invented the telephone, wireless communication, and the FM radio? What is conventional AM? For color television, what modulation formats are (i.e. the kind of FM and AM modulation) used for transmitting the luminance signal, the chrominance signal, and the audio signal? Describe briefly how stereophonic FM is transmitted

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

View Full Document
Problem 2 (Huffman Coding) We have an alphabet of 2 letters } , { b a of probabilities 1/3 and 2/3. What is the entropy of this alphabet? Now give a binary code for this alphabet. Compared to the entropy of the source, how much more transmission is needed per letter on average? (10%) To approach the source entropy for the number of bits per letter transmitted, we group 3 letters together (such as aaa, aab, aba, abb etc. with probabilities 1/27, 2/27, 2/27, 8/27, etc.) to make up codes.

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.

Unformatted text preview: Use Huffman coding to find the binary codes. What is the average coded message length? Problem 3 Plot the Fourier Transforms for t f A t c c 2 cos ) ( = and for t f t f t m m m sin ) ( = ? (You may choose to forfeit the points and ask the TA to give you an answer). Plot the spectrum of the AM modulated signal t f t Am t u c 2 cos ) ( ) ( = . What is the energy of the AM modulated signal? Now suppose we use Phase Modulation with 10 = p k , what is the bandwidth of the PM signal? Now suppose we use Frequency Modulation with 10 = f k , what is the bandwidth of the FM signal? Describe how you would obtain SSB-SC from ) ( t u , and plot the corresponding spectrum. We use a BPF given as follows to filter ) ( t u to give ) ( t v . Plot the spectrum of the resulting signal....
View Full Document

## This note was uploaded on 11/01/2009 for the course EEE 455 taught by Professor Hui during the Spring '09 term at ASU.

### Page1 / 4

q1_03 - Use Huffman coding to find the binary codes. What...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online