Microwave Electronics

Pre-Requisite: EC308
Contact Hours and Credits: (3 -0- 0) 3


To impart knowledge on basics of microwave electron beam devices and their applications in X band frequency.

Topics Covered:

Klystrons: Limitations of conventional vacuum tubes, Two cavity klystron  - Reentrant cavities, Velocity modulation process, Bunching process ,Power output and efficiency; Multi-cavity klystron , Reflex klystron- Velocity modulation process, Bunching process, Power output and efficiency ,  Mode Characteristics ,Electronic admittance spiral.

Travelling-wave tubes: Slow-wave structures, Helix TWT- Amplification process, Convection current, Wave modes and gain; Coupled cavity TWT, Backward wave oscillator.

Crossed -field devices: Magnetrons- Principle of operation, characteristics, Hull cut-off condition; Carcinotron, Gyrotron.

Microwave transistors and FETs: Microwave bipolar transistors-Physical structures, characteristics, Power-frequency limitations; Microwave tunnel diode, Microwave unipolar transistor – Physical structure, principle of operation, characteristics ,High electron-mobility transistors.

Transferred electron and Avalanche transit-time devices : Gunn diode, Gunn diode as an oscillator. IMPATT, TRAPATT and BARITT.

Course Outcomes:

Students are able to

  • CO1: Apply the basic knowledge of waveguide and microwave resonator circuits.
  • CO2: Asses the methods used for generation and amplification of the microwave power.
  • CO3: Distinguish between the linear and cross field electron beam microwave tubes.
  • CO4: Critically analyze the operating principles and performances of the microwave semiconductor devices.
  • CO5: Identify the suitable microwave power sources of given specification for the selected application.
  • CO6: Aware of current technological changes in the engineering aspects of microwave components.

Text Books:

  • S.Y. Liao, Microwave Devices and Circuits (3/e), PHI(2005).

Reference Books:

  • R.E. Collin, Foundations for Microwave Engineering (2/e) , Wiley India(2007).
  • D.M. Pozar, Microwave Engineering (3/e) Wiley India (2009).