Day 1: RF Wave Characteristics Flashcards
(44 cards)
One positive and negative iteration of a wave representing a full 360
Cycle
Time it takes to complete one cycle, measured in Seconds
Period
Number of cycles completed in one second, measured in Hertz
Frequency
Denotes the particular point in the cycle of a waveform, measured as an angle in degrees
Phase
The distance of one cycle, measured at the beginning and end of the waveform
Wavelength
Value of the power of the sine wave, often measured in decibels (dB)
Amplitude
The larger the amplitude, the more what?
Power the signal has
What is the relationship between wavelength and frequency?
Inversely proportional; shorter wavelength, higher frequency
How an EM wave travels through a medium, such as the atmosphere or space, from a transmitter to a receiver
Signal Propagation
Repeat a pattern over subsequent identical periods
Periodic Signals
In most data communications, we see periodic ______ signals.
Analog
Occurs when the signal bounces off a surface in a different direction
Reflection
Occurs when the signal bends around an object
Diffraction
Occurs when the signal encounters small objects of size and gets scattered in multiple directions
Scattering
Power loss between the transmitter and receiver due to the spreading of the wave’s energy
Free Space Loss
Rapid and random changes to a wave’s amplitude, phase, and polarity caused by charged (ionized) particles as a wave travels through the Earth’s Ionosphere
Scintillation
Affects signals in the UHF frequency range the most significantly (lower frequencies)
- Scintillation
- Faraday Rotation
When an electromagnetic (EM) wave’s polarization direction twists as it passes through a magnetic field in a medium, like the Earth’s ionosphere
Faraday Rotation
Higher frequencies are more likely to be absorbed or scattered by water and other molecules due to the shorter wavelengths being of a similar size, resulting in power loss
Water/Atmo Absorption
Higher energy waves have a natural tendency to spread out faster, and therefore are more susceptible to _____.
Free Space Loss
Refers to the direction of an electromagnetic wave’s E-field in reference to the earth’s surface
Polarization
To adjust the orientation of your polarizer relative to the EM wave to align with it, is called what?
Pol’ing
What are the two categories of polarization?
Linear and Circular
What are the two linear polarization?
Vertical
Horizontal
