Noise in Communication
Table of Contents
Noise in Communication
What is Noise?
Noise is an unwanted signal that tampers with the primary message signal and tampers with its parameters. Because of this change in the communication process, the message is changed. Most likely, it will be entered at the receiver or the channel.
The noise signal can be understood by taking a look at the following example.
So it follows that a signal that lacks a pattern and a constant frequency or amplitude is considered to be noise. It is very haphazard and uncertain. There are usually steps taken to lessen it, even though it cannot be completely stopped.
Most common examples of noise are −
- Buzz sound amidst of telephone conversations
- Hiss sound in radio receivers
- Flicker in television receivers, etc.
Effects of Noise
Noise is an annoying aspect that degrades system efficiency. The following are noise’s effects.
Noise limits the operating range of the systems
The weakest signal that an amplifier can amplify is indirectly limited by noise. Due to noise, the oscillator in the mixer circuit might have a frequency limit. The functionality of a system is dependent on how well its circuits work. The smallest signal that a receiver can process is constrained by noise.
Noise affects the sensitivity of receivers
Sensitivity is the smallest amount of input signal required to produce an output with the desired quality. A receiver system’s sensitivity is impacted by noise, which eventually has an impact on the output.
Types of Noise
Noise is categorized based on the type of source, the effect it produces, the relationship it has with the receiver, etc. Noise is primarily created in one of two ways. One comes from an external source, whereas the other is produced internally, in the receiver section.
External Source
This noise is typically caused by outside factors that could affect the communication channel or medium. It is impossible to completely stop this noise. Preventing noise from affecting the signal is the best course of action.
Examples
Most common examples of this type of noise are −
- Extra-terrestrial noise, such as solar noise and cosmic noise.
- Atmospheric noise (due to irregularities in the atmosphere).
- Industrial noise.
Internal Source
When the receiver is operating, its components make this noise. Due to their continuous operation, circuit components may produce a variety of noise. This noise can be measured. The impact of this internal noise may be lessened with an appropriate receiver design.
Examples
Most common examples of this type of noise are −
- Shot noise (due to the random movement of electrons and holes).
- Thermal agitation noise (Johnson noise or Electrical noise).
- Another type of noise is miscellaneous noise, which includes noise produced by mixers, flicker, and resistance effects.
- Transit-time noise (during transition).