Name: ________________________________________________________________ CS4323
1. Let 0  t  1. Find the
a. Amplitude
b. Frequency
c. Period
d. Phase
For the functions
A.
f (t )  sin( 2  t )
B.
f (t )  6 sin( 8  t )

C.
f (t )  sin(
 t)
2
D. f (t )  120 sin( 60  t )
E.
f (t )  3 sin( 4  t 

2
)
2. T  12 s, find f in MHz.
3. What is the bandwidth of a signal that can be decomposed into five sine waves with
frequencies at 0, 20, 50, 100, and 200Hz?
a. Draw an amplitude vs frequency plot if the amplitudes are 10, 5, 1, 2, 3
respectively.
b. Is this signal periodic?
4. What is the bandwidth of a signal containing one frequency = 1kHz?
5. A device is sending out data at the rate of 100bps.
a. How long does it take to send 10 bits?
b. How long does it take to send one character?
c. How long does it take to send a file with 100k characters?
6. A TV channel has a bandwidth of 6MHz. If the digital signal uses one channel, what are
the data rates if we use:
a. The first harmonic only?
b. The first and third harmonic?
7. The attenuation of a signal is -10dB. What is the final signal power if it started out at 5
Watts?
8. If the bandwidth of the channel is 5kbps, how long does it take to send a frame of 100kb?
9. A signal has a wavelength of 1  m. How far can the front of the wave travel during 1000
periods? Express the answer in mm.
10. A telephone line with bandwidth 4kHz, has a signal strength of 10V, and a noise level of
5V. What is the maximum data rate supported by this telephone line?
11. A computer monitor has a resolution of 1200x1000 pixels. If each pixel uses 1024 colors,
how many bits are needed to send the complete contents of the screen?
12. If the peak voltage value of a signal is 20 times the peak voltage value of the noise,
calculate the SNR and the SNR(dB).
13. How many bits can fit on a link with a 2ms delay if the bandwidth of the link is 1 Mbps?
14. How much is the capacity of a link improved (bps) if the bandwidth in Hz is doubled?
15. How much is the capacity of a link improved (bps) if the SNR is doubled?
16. What is the transmission time of a packet sent by a station if the length of the packet is
1MB and the channel bandwidth is 200 Kbps?
17. What is the difference between baseband and broadband transmissions?
18. What is the Nyquist Theorem Bit Rate?
19. Why do optical signals used in fiber optic cables have very short wave lengths?
20. Is a modulated signal baseband or broadband?