100 likes | 238 Views
Chapter 3 Radio Frequency Components, Measurements, and Mathematics. Key Terms & Concepts. 3 Basic Requirements for Communication Two or more devices want to communicate Medium or method for them to communicate Set of rules for them to use. Key Terms & Concepts. Transmitter
E N D
Chapter 3Radio Frequency Components, Measurements, and Mathematics
Key Terms & Concepts • 3 Basic Requirements for Communication • Two or more devices want to communicate • Medium or method for them to communicate • Set of rules for them to use
Key Terms & Concepts • Transmitter • Generates signal at specific frequency • Determines amplitude (power level) of signal • Antenna • Collects AC signal that receives from transmitter • Directs, or radiates, RF waves away from the antenna in a specific pattern
Key Terms & Concepts • Receiver • Receives the signal from the antenna and translates the signal into 1s and 0s • Intentional Radiator (IR) • Specifically designed to generate RF • Consists of all components from transmitter to antenna, excluding antenna
Key Terms & Concepts • Equivalent Isotropically Radiated Power (EIRP) • Highest RF signal strength transmitted from antenna • Focuses the RF generated by the IR and makes it stronger
Key Terms & Concepts • Units of Power • Watt • 1 Watt = 1 ampere (amp) of current flowing at 1 volt • Amp is current • Voltage is pressure generated • Amount of watts generated = volts X amps • Milliwatt (mW) • 1/1,000 of a watt • Decibels relative to 1 milliwatt (dBm) • Compares signal to 1 milliwatt of power • 0 dBm = 1 milliwatt
Units of Comparison Decibel (dB) Represents difference btw 2 values Decibels isotropic (dBi) Gain or increase of power from an antenna when compared to what an isotropic radiator would generate Key Terms & Concepts
Key Terms & Concepts • Units of Comparison • Decibels dipole (dBd) • Increase in gain of an antenna when it is compared to the signal of a dipole antenna • If antenna has value of 3 dBd, it is 3 dB greater than a dipole antenna