Modulation

Modulation

AM power distribution
1. Current calculations
Calculation of modulation index
Bandwidth / frequency range
1. BW increases with increase in rate of data transmission
Types of modulation
1. Analog modulation
2. Digital modulation
Modulation by complex signals
Mathematical representation
1. Time domain description
2. Frequency domain discription
Why modulate
1. Reduces antenna height
  1. lamda = speed of light / frequency
    1. height of antenna = lamda / 4
2. Avoids mixing of signals
  1. Frequency slot allocation
3. Increases range of communication
  1. frequency increases / attenuation decreases
4. Improves signal reception quality
  1. Signal noise reduces due to modulation techniques
AM transmitters
1. Low level
2. High level
Disadvantage
1. power inefficient
2. Bandwidth inefficient
3. Prone to noise
Modulation index
1. Linear modulation m<=1
2. Over modulation

Zusammenfassung der Ressource

	Erstellt von log2022 vor etwa 12 Jahre