analog waveforms

Assignment No 2

1. Convert the binary data “011010” into analog waveforms using following modulation

techniques:

a. Two level Amplitude Shift Keying

b. Two level Frequency Shift Keying

c. Two level Phase Shift Keying

d. Differential Phase shift keying

e. Four level Amplitude Shift Keying

f. Four level Phase Shift Keying

g. Eight level Amplitude Shift Keying

2. With fc = 500 kHz, fd = 25 kHz, and M = 16 (L = 4 bits), compute the frequency

assignments for each of the sixteen possible 4-bit data combinations.

3. Draw the approximate Analog Modulation and Frequency Modulation waveforms in

complete steps for the following signal:

4. Draw the 16 QAM Constellation Diagram having two different amplitude levels and eight

different phase levels.

5. Explain and draw the Error Detection Process for Cyclic Redundancy Check (CRC).

6. Compute the frame check sequence for the following information:

Message = 10111100, Pattern = 11011

7. Compute the transmitted signal using Direct Sequence Spread Spectrum for the

following information:

Input: 1011, Locally Generated PN bit stream: 101011011010, T = 3Tc

8. What is the difference between Infrastructure and ad hoc modes in WLAN? Draw their

relative diagrams as well.

9. Compare the differences of TCP and OSI protocols for wired and wireless LANs using

diagrams.

10. Explain why the square and circle shapes cells for cellular communications are not

appropriate as compared to hexagonal shape cells.