Chapter 2 Flashcards
What is EM?
Electromagnetic Spectrum
Which is usually simply referred to as spectrum is the range of all possible electromagnetic radiation.
Low Frequency?
High Frequency?
Low Frequency - Long Wavelength
High Frequency - Short Wavelength
How much is 1 Ghz?
1,000,000,000 (billion) cycles per second
What is Absorption?
When signal gets absorbed by some material.
Leading cause of attenuation (loss)
What is Reflection?
When wave bounces off a material.
Sky Wave Reflection?
Can occur in frequencies below 1Ghz, where the signal has very large wavelength.
Microwave Reflection?
Exist between 1Ghz and 300Ghz. Much smaller frequencies
Scattering?
Scattering is multiple reflections.
Chain link fences, tree folliage, rocky terrain.
Refraction?
Bending of RF signal
FSPL?
Free Space Path Loss
Is the loss of signal strength caused by the natural broadening of the waves.
Multipath?
Is a propagation phenomenon that results in two or more paths of a signal arriving at the same time or within nanoseconds of each other.
Four possible results of Multipath?
Upfade
Downfade
Nulling
Data Corruption
What is Upfade?
Increased signal strength.
What is Downfade?
Decreased signal strength.
What is Nulling?
Signal cancellation