Section 2-D Flashcards
Waveguides
Special transmission lines that operate above 1GHz. They operate in the microwave range.
Cylindrical Waveguide
A coaxial line with the center hollowed out. They come in three different types Circular, Elliptical and Rectangle
A Wall
The wall that is determined by the operating frequency of the waveguide.
B Wall
The Wall that is determined by the amount of power that will transmit through the wave guide.
Advantages of a waveguide
- copper loss is small due to large surface area
- dielectric losses are small (no center conductor)
- can handle more power (more space between conductors)
- radiation loss, radiation is contained within the waveguide
Disadvantages of a waveguide
- incredibly massive at lower frequencies
- limited bandwidth
Cut-off Frequency
The lowest frequency that can go down the waveguide with maximum signal strength.
Electrolysis
Corrosion brought on by the pairing of two dissimilar metals.
Air Dessicants
Removes moisture from waveguides.
- (blue) when no moisture
- (pink) when moisture is absorbed
Threats to waveguides
Moisture
Corrosion
Dirt
Dents
Waveguide coupling
Device used to measure power, frequency and source leveling within a waveguide.
3 types of coupling
Probe
Loop
Slot/ aperture
Probe Coupling
A probe projecting into a waveguide or cavity resonator, designed to transfer energy to or from an external circuit.
Loop Coupling
A method of transferring energy between a waveguide and an external circuit, by inserting a conducting loop into the waveguide, oriented so that electric lines of flux pass through it.
Slot/Aperture Coupling
Energy enters through small slot in waveguide. E field expands through wave guide.
