What is an adjacent channel interference (ACI)? ACI may be caused by inadequate filtering, improper tuning and poor frequency control
Mention 4 ways by which adjacent channel interference can be reduced or eliminated.
- Using modulation which shows the scheme have low out-of-bound radiation.
- Carefully designing the bandpass filter at the receiver front
- Assigning adjacent channel to different cells in order to keep the frequency separation between each channel in a given cell as large as possible.
- Accurate filtering and channel allocation ( maximizing channel intervals of the cell)
Frequency deviation: it is used in FM radio to describe the difference between the minimum or maximum extent of a frequency modulated signal and the nominal center or carrier frequency.
Side frequency: The frequency of oscillation that appears along with the principal carrier frequency is when the oscillation are modulated. They differ from the carrier frequency by a value that is either equal to or a multiple of the frequency of the modulating signal.
Modulating index: It’s defined as a measure of the extent of modulation done on a carrier signal wave. In amplitude modulation, it can be defined as the ratio of the amplitude of a modulating signal to that of the amplitude of carrier signal.
Side band: Is the portion of modulating carrier waves that is either above or below the basic (baseband) signal. The portion above baseband signal is the upper sideband while the portion below is the lower sideband.
