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ultimateguy
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I was wondering if someone could give me some ways to combat Johnson noise and shot noise.
Thanks
Thanks
ultimateguy said:There isn't really a context. I'm in an instrumentation class, and one of the questions is "Describe the origins of Johnson noise and Shot noise and appropriate countermeasures you can take to deal with them."
I know what they are, but I've been trying for the life of me to find out what the countermeasures are. I don't have them in my class notes and they're not in the textbook.
Johnson noise, also known as thermal noise, is a type of noise that arises from the random thermal motion of electrons in a conductor. It is present in all electrical circuits and is a fundamental limit to the minimum amount of noise that can be achieved in a system.
Johnson noise is a type of noise that is present in all electrical circuits, while shot noise is a type of noise that occurs when a current is carried by individual particles, such as electrons. Shot noise is caused by the discrete nature of the particles and is present in systems where the current is low and the number of particles is small.
Johnson noise can be measured using a spectrum analyzer or an oscilloscope. By measuring the noise power over a range of frequencies, the Johnson noise can be determined. The noise level is directly proportional to the temperature of the conductor and the bandwidth of the measurement.
Johnson noise can affect electronic devices in several ways. It can increase the noise level in a circuit, reducing the signal-to-noise ratio and potentially degrading the performance of the device. It can also lead to errors in measurements and limit the sensitivity of certain devices.
Johnson noise can be reduced by cooling the conductor, as the noise level is directly proportional to temperature. This is one of the reasons why electronic devices, such as transistors and amplifiers, are often designed to operate at lower temperatures. Additionally, using low-noise components and optimizing the design of the circuit can help reduce Johnson noise.