Yarmouk University
Hijjawi Faculty of Engineering and Technology
Department of Communication Engineering
Microwave Systems Lab (CME447a)
Part 3: Microwaves
Experiment 3:
Measurement of Microwave power
Objectives:
Upon completion of the laboratory study and experimentation, the student will be able to:
[1].
[2].
[3].
Background Discussion
Part 2
Microwave Antennas
Page 1
Yarmouk University
Hijjawi Faculty of Engineering and Technology
Department of Communication Engineering
Power Measuring Circuit
Part 2
Microwave Antennas
Page 2
Yarmouk University
Hijjawi Faculty of Engineering and Technology
Department of Communication Engineering
Equipment Required
Experimental Procedures
1. Connect the Bolometer to the bridge as shown above, slowly raise the bridge
current and watch the meter. Adjust the bridge current until the meter needle is
central, checking the balance of the bridge and adjust it if necessary to fill the
table below:
Attenuators Bridge current d.c power in
(mA)
setting(degrees)
thermistor(mw)
r.f power in
thermistor
(mw)
Oscillator is OFF
Part 2
Microwave Antennas
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Yarmouk University
Hijjawi Faculty of Engineering and Technology
Department of Communication Engineering
Calculations:
Conclusion:
Part 2
Microwave Antennas
Page 4
Yarmouk University
Hijjawi Faculty of Engineering and Technology
Department of Communication Engineering
Experiment 4:
Measurement of Voltage Standing Wave Ratio (VSWR)
Objectives:
Upon completion of the laboratory study and experimentation, the student will be able to:
[1].
[2].
[3].
Background and Discussion
Part 2
Microwave Antennas
Page 5
Yarmouk University
Hijjawi Faculty of Engineering and Technology
Department of Communication Engineering
Material Required:
Experimental Procedures
1. Set up test fixture in figure 2-4.
2. Using the Slotted Line Detector output to complete the table shown below:
Distance along the line
(cm)
Meter readings(μA)
part 1 (………..dB)
Meter readings(μA)
part2 (………..dB)
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
Part 2
Microwave Antennas
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Yarmouk University
Hijjawi Faculty of Engineering and Technology
Department of Communication Engineering
2.6
2.8
3.0
3.2
3.4
3.6
3.8
4.0
3. Plot a curve of distance and readings for the two above cases.
4. Calculating the voltage standing wave ratio (VSWR) for different source and
load attenuator settings. In each time we use the Normal and the Double
Minimum Method (Avoiding the case of 0 dB with 0 dB attenuator setting)
and complete the table below:
Attenuators
settings
Part 2
Microwave Antennas
Imax
Imin
d
VSWR
VSWR
Method-1
Method-2
Page 7
Yarmouk University
Hijjawi Faculty of Engineering and Technology
Department of Communication Engineering
Calculations:
Conclusion:
Part 2
Microwave Antennas
Page 8