Cavity resonator fundamentals

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Cavity Resonator
Dr. A. Petrishia
Associate Professor
TRP Engineering College

2. Outline
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 Introduction
 Wave guides
 Cavity Resonators
 Types of Cavity Resonator
Rectangular Cavity Resonator
Circular Cavity Resonator
 Applications
 Conclusion

3. Waveguides
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 The two-wire transmission line used in conventional circuits is
inefficient for transferring electromagnetic energy at microwave
frequencies
 Structure guide electromagnetic waves at microwave frequencies
 a- operating frequencies- 0.7λ
 b- power handling capacity- 0.2 -0.5 λ
 https://www.youtube.com/watch?v=-4cUv92FCqM

4. Introduction
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 A cavity resonator is a useful microwave device

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Introduction

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8. UWB system
Ultra Wideband – High Bandwidth, FCC - 2002
IEEE 802.15.3a
Foremost communication systems are based on
sinusoidal waves
UWB systems are based on exchanging data using short
duration pulses of sub nanoseconds which covers a very
wide bandwidth in the frequency domain - hence the name
Ultra WideBand

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H L
c
f -f
f

10. UWB system features
Unlicensed spectrum
Ultra short pulses – High data rate
Base band transmission – Simple transceiver
design
Low duty cycle – High energy efficiency
Low probability of detect/intercept –extremely low
pulse width
Immunity to multipath fading
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11. UWB Antenna
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Capable of receiving all frequencies at the same time
Electrical size must be small with high efficiency
Pulse distortion must be kept to a minimum
Constant radiation pattern through out the band of
operation

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Directional Omni Directional
Gain High Low
Antenna Size Large Small
Field of View Narrow Wide

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