ECE 5930 / 6930 Wireless Communication
Midterm I
Name _______________________________________
You may use your portfolio and a calculator, but no textbook.
____ ECE 5930
____ ECE 6930
|
Cell Splitting |
Cell Sectoring |
||||
# of users U |
Decrease |
NoChange |
Increase |
Decrease |
NoChange |
Increase |
S/I |
Decrease |
NoChange |
Increase |
Decrease |
NoChange |
Increase |
Ptx (basestation) |
Decrease |
NoChange |
Increase |
Decrease |
NoChange |
Increase |
Given:
Height of basestation transmitter 100 meters
Height of receiving antenna 2 meters
Frequency 1900 MHz
Distance between TX and RX 1 km
Sensitivity of the phone -100 dB
Maximum power of the phone 1 Watt
Losses in the basestation receiver 5 dB
Gain of basestation antenna 5 dBi
Gain of phone antenna 1.6 dBi
Environment:
USU campus, including buildings and trees.
a. Evaluate the following models for determining the path loss between phone and basestation. Explain the limitations of each model for this application:
Friis transmission equation
Ground Bounce Model
Reflection Model
Log-Distance Model
Okumura Model
Hata Model
b. Using the Okumura model, prepare a link budget to determine the power received by the basestation when the phone is transmitting. Neglect losses not given above or indicated in your model.
c. Explain “path balance” and why it is important.
Explain why.
What value(s) obtained from the
A mobile user is traveling 60 mph
when his call is handed from one basestation to another. The call is accidentally disconnected. List at least five different things that
could have gone wrong.
ECE 5930/6930 Midterm I
Name ________________________________
Problem 1 __________ / 33 points
Problem 2 __________ / 33 points
Problem 3 __________ / 15 points
Problem 4 __________ / 19 points
Total __________ / 100 points