Microwave Transmission Lines : Microwave spectrum and bands, Applications of microwaves. Rectangular Waveguides TE/TM mode analysis, Expressions for fields, Characteristic equation and cut-off frequencies, Filter characteristics, Dominant and degenerate modes, Sketches of TE and TM mode fields in the cross-section, Mode characteristics Phase and group velocities, Wavelengths and impedance relations; Power transmission and power losses in rectangular guide. Related problems.Circular Waveguides : Nature of fields, Characteristic equation, Dominant and degenerate modes. Impossibility of TEM mode. Microstrip lines Introduction, Z0 relations, Effective dielectric constant, Losses, Q factor. Cavity Resonators Introduction, Rectangular and cylindrical cavities, Dominant modes and resonant frequencies, Q factor and coupling coefficients. Related problems.Waveguide Components and Applications - I : Coupling mechanisms Probe, Loop, Aperture types. Waveguide discontinuities Waveguide irises, Tuning screws and posts, Matched Loads. Waveguide attenuators Resistive card, Rotary vane types; Waveguide phase shifters Dielectric, Rotary vane types. Waveguide multiport junctions E plane and H plane tees, Magic tee, Hybrid ring ; Directional couplers 2 Hole, Bethe hole types.Waveguide Components and Applications - II : Ferrites Composition and characteristics, Faraday rotation; Ferrite components Gyrator, Isolator, Circulator. Scattering matrix Significance, Formulation and properties. S matrix calculations for 2 port junction, E plane and H plane tees, Magic tee, Directional coupler, Circulator and isolator. Related problems.Microwave Tubes - I : Limitations and losses of conventional tubes at microwave frequencies. Microwave tubes O type and M type classifications. O-type tubes : 2 Cavity Klystrons Structure, Reentrant cavities, Velocity modulation process and applegate diagram, Bunching process and small signal theory Expressions for o/p power and efficiency. Reflex Klystrons Structure, Applegate diagram and principle of working, Mathematical theory of bunching, Power output, Efficiency, Electronic admittance; Oscillating modes and o/p characteristics, Electronic and mechanical tuning. Related problems.Helix TWTs: Significance, Types and characteristics of slow wave structures; Structure of TWT and amplification process (qualitative treatment), Suppression of oscillations, Nature of the four propagation constants, Gain considerations.M-type Tubes : Introduction, Cross-field effects, Magnetrons Different types, 8-Cavity cylindrical travelling wave Magnetron Hull cut-off and Hartree conditions, Modes of resonance and PI-Mode operation, Separation of PI-Mode, O/P characteristics.Microwave Solid State Devices : Introduction, Classification, Applications. TEDs Introduction, Gunn diode Principle, RWH theory, Characteristics, Basic modes of operation, Oscillation modes. Avalanche transit time devices Introduction, IMPATT and TRAPATT diodes Principle of operation and characteristics.Microwave Measurements : Description of microwave bench Different blocks and their features, Precautions; Microwave power measurement Bolometer method. Measurement of attenuation, Frequency, VSWR, Cavity Q. Impedance measurements.Microwave Transmission Lines : Microwave spectrum and bands, Applications of microwaves.
|Publisher||:||Technical Publications - 2009-01-01|