Velammal College of Engineering and Technology, Madurai Department of Electronics and Communication Engineering Question Bank Subject Name: EC2353 Antennas And Wave Propagation Faculty: Mrs G VShirley Julia Academic Year: 2015-16 Semester/Branch: VI/ECE Unit I 1) What are scattering coefficients? 2) Write down S matrix for N port Network? 3) State the phase shift property of s matrix? 4) What are the advantages of S-matrix over Z and Y matrix? 5) State the unitary property of S matrix? 6) Define hybrid parameters? 7) Define transmission matrix? 8) Define ABCD parameter in terms of Z parameter? 9) When S matrix is symmetric? 10) Write down condition for reciprocal and lossless network? 11) Draw the equivalent Circuit of High frequency Inductor & Capacitor? 12) Draw frequency response of impendence of RFC? 13) Name the different types of high frequency resistor? 14) Draw equivalent circuit of High frequency wire wound resistor? 15) Scattering Matrix from measured from the S parameter of two port network given below: [s]=. From the above data, determine the network is symmetric or not. PART B 1) Compare Z, Y, and h and ABCD parameters? 2) State & explain any four properties of S matrix. 3) What is Transmission matrix? Obtain an expression of a cascade connection of Transmission matrix? 4) Write short notes on (i) RF component of wire (ii) High frequency inductor 5) Write short notes on (i) High frequency resistor (ii) High frequency capacitor 6) State and explain for S matrix of an N port network? 7) Discuss the various applications of RF. 8)Discuss the reasons for using S parameters at high frequencies and also explain the properties with proof Unit II
1) What is impedance Matching Network? 2) Draw any two types of two component L section matching networks. 3) Name different types of Stabilization in RF Circuits 4) Write the unilateral Power Gain (G TU ) of a Single Stage RF Power Amplifier. 5) What is meant by Rolette factor (K)? 6) Define Quality factor. 7) Draw the structure of section matching networks. 8) What is meant by forbidden region in a Matching network? 9) Define Noise Figure. 10) What are the different types of Microstripline Matching networks? PART B 1. Discuss in detail about Power relations of a Single Stage RF power amplifier. 2. Write short notes on (i) Stability and (ii) Gain considerations of RF amplifier. 3. What is impedance Matching Network? How many network topologies exist in a Two component matching nework? Draw and Explain. 4. Explain with a neat Sketch T & section matching networks. 5 (i) Write about Frequency Response of Matching Networks (ii) What are the design procedures of matching networks using Smith chart Write short notes on Microstripline Matching Networks (ii) What are the advantages of Impedance Matching Networks? 6. (i) Unit III 1. Give the X band frequency range. 2. State the properties of S matrix of lossless, reciprocal, perfectly matched network. 3. What are Micro waves? State their applications. 4. Write down the ABCD parameters of a lossless transmission line. 5. Give the applications of directional coupler 6. Name some wave guide components used to change the direction of the guide 7. What is Tee junction? Give two examples 8. What should be the minimum radius of curvature for E plane bend and H plane bend? Validate your answer. 9. What are nonreciprocal devices? Give two examples 10. Difference between Isolator and Circulator? 11. Write down the Scattering Matrix of an ideal lossless transmission line. 12. What is the principle of Microwave phase shifter?
13. What do you meant by Faraday rotation Isolator? 14. Define the directivity of Directional Coupler. 15. what are called Resonators? 1. (i) What is a Hybrid ring. With the help of a neat diagram explain its working principle. (ii) Derive scattering matrix of H-plane Tee using S-parameters theory. 2. (i) What are the advantages of S-parameters over Z or Y parameters. (ii) What is the directivity of an ideal directional coupler? Why. (iii) From the first principles derive the scattering matrix of an ideal Directional coupler 3. (i) What is scattering matrix? Derive scattering matrix formulation for N-port network (8) (ii) Derive scattering matrix for E-plane Tee using 'S' parameter theory. (8) 4. (i)what is the function of an isolator? Write down its 'S' parameters. (4) (ii)explain the working of a circulator and hence obtain the scattering matrix of the Circulator from the first principle. (12) 5. Derive the S Matrix of the Magic Tee. 6. Explain with neat diagrams waveguide Corners, Bends and Twists. 7. A Three port circulator has an insertion loss of 1 db, an isolation of 20 db, and VSWR of 1.2 when all the ports are matched and terminated. Find the S Matrix of the junction and output power at ports 2 and 3 for an input power of 100 mw at port 1. 8.Prove that it is not possible to construct a perfectly matched, lossless, reciprocal 3port junction. 9)(i) What is scattering matrix? Derive scattering matrix formulation for N-port network (ii) Derive scattering matrix for E-plane Tee using 'S' parameter theory. Unit IV 1. What are HEMT s? 2. What is MESFET? 3. Define GUNN effect. 4. What is the necessary condition for an IMPATT to produce oscillations? 5. List the differences between microwave transistor and TED devices. 6. What are the advantages and disadvantages of parametric amplifier? 7. What is meant by avalanche transit time device? 8. Discuss the applications of PIN diode. 9. What is a parametric amplifier? How is it different from a normal amplifier? 10. Mention the basic materials required for microwave integrated circuit. 11. What are the advantages of MMIC over discrete circuit? 12. What are the properties of dielectric materials?
13. List the various MMIC fabrication techniques. 14. List the advantages of Microwave IC's. 15. Name the different types of lithography. 1.(i) Explain the constructional details and operation of GaAs MESFET with neat diagrams and characteristics curves. 2. (i) What are avalanche transit time devices. (ii) With a neat diagram explain the construction and operating principle of IMPATT diode. (iii) Mention any two applications of IMPATT diode. 3. Enumerate with appropriate equations the power frequency limitations of BJT's at high frequencies. (16) 4. Write short notes on: (i) Microwave FET's (8) (ii) HEMT (8) 5. Derive the Manley Rowe power relation. Show how it can be applied to find the gain of up converter and down converter. 6. (i) Write down RWH theory of Gunn diode.(ii) Explain the various modes of operation of Gunn diode. 7. Explain the following: (i) BARITT diode (ii) TRAPATT Diode (iii) Varactor diode and (iv) Step recovery diodes 8. (i)list the basic characteristics required for an ideal substrate material. (4) (ii)explain in detail with suitable diagrams the fabrication techniques of a monolithic microwave integrated circuit. Unit V 1. What is transferred electron effect? 2. What is velocity modulation? 3. Draw the electronic admittance diagram of reflex klystron. 4. State the differences between TWT and klystron? 5. Can a two cavity klystron amplifier be used an oscillator? If yes, how? 6. What is the purpose of slow wave structures in TWT? 7. How is bunching achieved in a cavity magnetron? 8. How is tuning achieved in reflex klystron oscillators? 9. What is strapping in magnetron? How is the same effect obtained without strapping? 10. Distinguish between ATD's and TED's. 11. Mention two methods to measure impedance. 12. Define return loss and write its expression 13. What is Bolometer? Give two examples?
14. A wave guide load is used to absorb power of 2W. Reflected power is 3mW.Find the VSWR. 15. What are the sources of error in return loss measurement using a waveguide reflectometer and klystron source? 16. Name two methods to measure the dielectric constant of a solid. 17. What is the principle by which high power measurements could be done by Calorimetric method? 18. How are microwave measurements different from low frequency measurements? 19. List the various techniques of measuring unknown frequency of a microwave generator. 20. How can you extend the range of power measurement? 21. Write the types of lithography 22. State the Applications of Reflex Klystron 1. (i) Describe with the neat sketch the constructional details and principle of operation of a reflex klystron tube. With the help of Applegate diagram illustrate the phenomenon of bunching. (ii) Derive expression for bunched beam current and efficiency. 2(i)Draw a neat sketch showing the constructional features of a cavity magnetron and explain why Magnetron is called as crossed field device. (4) (ii)derive an expression for cut off magnetic field for a cylindrical magnetron. (8) (iii)explain how 'strapping' enables the separation of II mode from other modes. (4) 3. Describe in detail with block diagram the measurement of VSWR through Return loss measurement. 4. Explain in detail the measurement of load impedance through slotted line method. 5. (i) With neat diagram explain the Insertion loss and Attenuation measurements. (8) (ii) Explain the measurement of load impedance by slotted line method. (8) 6. (i)describe with neat diagram and mathematical formulation the measurement of Dielectric constant of a solid using rectangular waveguide. (8) (ii)explain the measurement of cavity 'Q' by slotted line method. (8)