What Is the Difference Between External and Internal Noise

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The Answer is External noise and internal noise are two categories of noise that can affect communication systems, electronic devices, and signal processing. Understanding the difference between these two types of noise is important for designing systems that can effectively minimize their impact.

External Noise:
External noise, also known as environmental noise, originates from outside the system or device. It is not inherent to the system's operation but comes from external sources. These sources can be natural or man-made. Examples of external noise include:

1. Electromagnetic interference (EMI) from other electronic devices, power lines, or radio transmitters.
2. Radio frequency interference (RFI) from broadcast stations or wireless devices.
3. Acoustic noise from engines, construction, or human activities.
4. Thermal noise from the environment, which can affect sensitive equipment.

External noise can be mitigated through shielding, filtering, and proper system design to ensure that the noise does not interfere with the desired signal.

Internal Noise:
Internal noise, on the other hand, is generated within the system or device itself. It is inherent to the operation of the electronic components and circuits. Examples of internal noise include:

1. Thermal noise or Johnson-Nyquist noise, which is generated by the random motion of electrons in a conductor due to temperature.
2. Shot noise, which is caused by the discrete nature of electric charge and the random arrival of charge carriers (electrons or holes) at a barrier or junction.
3. Flicker noise or 1/f noise, which is a low-frequency noise that occurs in semiconductor devices due to carrier density fluctuations.
4. Burst noise or popcorn noise, which consists of sudden step-like transitions between different levels, typically in semiconductor devices.

Internal noise is often addressed by improving component quality, using low-noise components, and optimizing circuit design to minimize the generation and impact of noise.

In summary, the main difference between external and internal noise lies in their origin: external noise comes from outside the system and can often be shielded against, while internal noise is generated within the system's components and must be managed through careful design and component selection. Both types of noise can degrade the performance of electronic systems and need to be considered in the design and operation of any sensitive equipment.

What Is the Difference Between External and Internal Noise

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