Ele569 2011 Exam Paper
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**** 2011 ****
ELE569 MICROWAVE ELECTRONICS Duration: 2 hours 30 minutes
YOU ARE NOT PERMITTED TO READ THE CONTENTS OF THIS QUESTION PAPER UNTIL INSTRUCTED TO DO SO BY AN INVIGILATOR.
Answer FOUR Questions. The Smith Chart is Attached.
calculators arE permitted in this examination. Please state on your answer book the name and type of machine used.
Complete all rough workings in the answer book and cross through any work which is not to be assessed.
important note: thE academic Regulations state that possession of unauthorised material at any time when a student is under examination conditions is an ASSESSMENT offence AND CAN LEAD TO EXPULSION FROM THE COLLEGE. Please CHECK NOW TO ENSURE YOU DO NOT HAVE ANY NOTES in your possession. IF YOU HAVE ANY THEN please RAISE YOUR hand AND GIVE them to AN invigilator IMMEDIATELY.
EXAM PAPERS CANNOT BE REMOVED FROM THE EXAM ROOM
Examiners: Prof. Y. Hao and Prof. C. G. Parini
© Queen Mary, University of London, 2010
Question 1
Answer the following questions on the Smith Chart and its applications.
(a) Starting from the definition of Reflection Coefficient, explain the construction of the Smith Chart. It is NOT necessary to derive the equations for the constant impedance and constant reactance circles.
[8 marks]
It is a polar plot of the complex reflection coefficient. It is also known as the 1-port scattering parameter s or s11, for reflections from a normalised complex load impedance z = r + jx;
[4 marks]
[2marks]
[2marks]
(b) Consider the transmission line circuit below (Figure 1). Use the Smith Chart to find SWR on the line, the return loss, the reflection coefficient at the load, the load admittance, the input impedance to the line, the distance to the first voltage minimum, the distance
**** 2011 ****
ELE569 MICROWAVE ELECTRONICS Duration: 2 hours 30 minutes
YOU ARE NOT PERMITTED TO READ THE CONTENTS OF THIS QUESTION PAPER UNTIL INSTRUCTED TO DO SO BY AN INVIGILATOR.
Answer FOUR Questions. The Smith Chart is Attached.
calculators arE permitted in this examination. Please state on your answer book the name and type of machine used.
Complete all rough workings in the answer book and cross through any work which is not to be assessed.
important note: thE academic Regulations state that possession of unauthorised material at any time when a student is under examination conditions is an ASSESSMENT offence AND CAN LEAD TO EXPULSION FROM THE COLLEGE. Please CHECK NOW TO ENSURE YOU DO NOT HAVE ANY NOTES in your possession. IF YOU HAVE ANY THEN please RAISE YOUR hand AND GIVE them to AN invigilator IMMEDIATELY.
EXAM PAPERS CANNOT BE REMOVED FROM THE EXAM ROOM
Examiners: Prof. Y. Hao and Prof. C. G. Parini
© Queen Mary, University of London, 2010
Question 1
Answer the following questions on the Smith Chart and its applications.
(a) Starting from the definition of Reflection Coefficient, explain the construction of the Smith Chart. It is NOT necessary to derive the equations for the constant impedance and constant reactance circles.
[8 marks]
It is a polar plot of the complex reflection coefficient. It is also known as the 1-port scattering parameter s or s11, for reflections from a normalised complex load impedance z = r + jx;
[4 marks]
[2marks]
[2marks]
(b) Consider the transmission line circuit below (Figure 1). Use the Smith Chart to find SWR on the line, the return loss, the reflection coefficient at the load, the load admittance, the input impedance to the line, the distance to the first voltage minimum, the distance