is, ; 76c
(a; 99’
31",)
23‘ rsi -
EE 439 RADIOWAVE PROPAGATION IN COMMUNICATIONS SP’ll
1; Exam #2 (90 minutes)
I"- «” Jig "i h 4
Name; jD é‘ran ﬂan? fail/ti;
(35%)
1. An AM broadcasting station operates on a frequency of 1 MHz with a transmitter power of

EE 439
RADIOWAVE PROPAGATION IN COMMUNICATIONS
Sample Exam #1
SP11
(15%)
1. An end loaded short dipole antenna has an effective length and gain h = h0 sin a and gain G = 1.5 sin2. An electromagnetic
wave is incident along the = /2 direction with an electr

EE 439
RADIOWAVE PROPAGATION IN COMMUNICATIONS
Sample Exam #2
(35%)
1. Two individuals use walkie-talkies operating at 150 MHz in a rural environment where the ground constants are
= 11, = 0.005 S/m. The antenna gains are equal to unity. The transmitted

334 ANTENNAS
and the Thevenin impedance is 02R where Q = woL/R and the resonant frequency is
given exactly by Eq. (5.31). Show that at the exact resonant frequency IVTHl2= ollvociz‘;
Note that RZC/L = 1/02. ' ’
5.4 Show in detail that Eqs. (5.32) and (5.3

452 PROPAGATION
6.5 A microwave relay link is to be designed such that the signal power level will not
be less than what it would be under free-space propagation conditions. The
frequency of operation is 10 GHz. The antenna heights at each terminal are 30

mum—Unit mm as. “44.”—
. . ._._._—.——._
454 PROPAGATION
6.19 A plane wave propagates along Bo in the ionosphere with f. = l_.4 MHz. The
frequency of the plane wave is 1.5 MHz. ,The electron density is 10“’/m3 and the collisio