Signal transmission over long distances often leads to a loss in the signal strength. To preserve the signal strength and combat this issue, designers often use amplifiers in combination with electronic circuits. While these amplifiers improve the signal strength, they often suffer from the effect of ‘noise.’
The term ‘noise’ can hold many meanings. The ‘noise’ could be a result of a minor distortion in an audio player or the clipping of an audio signal. Noise in an amplifier normally comes from different sources and can affect the signal in different ways.
Knowing about the noise source can help you in minimizing its effects better.
— Atmospheric Noise
Also known as static noise, atmospheric noise results from thunderstorms and other electrical disturbances in the atmosphere.
These electrical disturbances generate spurious signals that are spread over a large frequency range. At any given point, the receiver not only picks up the signal but the noise component as well. Since these components are random in nature, there’s no defined process for their elimination. The only way to prevent the signal is by improving the hardware design, making it less susceptible to extrinsic factors.
— Thermal Noise
The electrons in a conductor are in continuous motion, vibrating and colliding against each other. This vibration is a function of temperature and constitutes the resistance offered by a conductor. However, this random motion of electron results in the addition of an extraneous voltage in the signal called “thermal noise.”
As we discussed above, the vibration of electrons depends on the operational temperature, which means the only way to minimize its effect is by reducing the surrounding temperature.
— Shot Noise
A common type of noise, this noise results due to irregular motion and arrival of electrons at the output terminal. It’s important to understand that even when you apply a biased voltage at the input terminal, there will be some discontinuities in the conductor that’ll cause the charge to scatter, resulting in output fluctuation. While its effect is almost negligible for high input levels, shot noise becomes a concerning factor for amplifiers operating at lower amplitudes.
Whatever be the source of noise, it affects the signal integrity—a grave problem in the world of signal processing. Using filters thus presents a viable solution to restore and separate the distorted signal.
If you’re looking for digital and FIR filters for electronic circuits, get in touch with ADSANTEC. Our range of products also includes delay lines, 4-bit ADC, clock dividers, phase detectors, and several other electronic components.
Contact us today for product details or customized design inquiry!