通过集中处理和约翰逊噪声和散粒噪声测量，TeachSpin的噪声基础，让学生以确定双方玻尔兹曼常数，KB ，电子电荷的幅度?#39;E'、/p>
约翰逊噪?/strong>的波动电动势在任?*温度?> 0 电阻油然而生。Nyquist的预测是，这个电动势的均方服仍em>
散粒噪声是衡量观察到的波动一定的电流，由于量化地对它们所加的粒度。在这种情况下，肖特的预测是一个直流电?em>成sub>直流服从另一均方有关的波动会伴随着，[成/em>＇em>?/em>）]2> = 2??/em>成sub>直流DF。此结果使要测量的基本电荶em>??/em>的大小、/p>
从这些来源之一，还有更多的噪音，可以观察到，因为模块化，用户可配置的，我们的电子安排。本装置的信号流的透明布局使得它很清楚如何在实践中量化噪声，由于过程的放大，滤波的频率，平方和平均的时间，可以单独和详细理解。其结果是量化噪声的方法，和噪声密度，学生其实可以理解。这会产生一个便携式的一套适用于整个测量科学的广度技能 噪声测量在物理学的许多领域中有一个非常当前的应用程序、/p>
Introduction
By concentrating on the processing and measurement of Johnson noise and shot noise TeachSpin’s Noise Fundamentals allows students to determine both Boltzmann’s constantkB and the magnitude of the charge on the electron ‗em>e?
Johnson noiseis the fluctuating emf which arises spontaneously in any resistor at absolute temperatureT> 0. Nyquist’s prediction is that the mean square of this emf obeys <V2(t) > = 4kBT RDf where Dfis the bandwidth over which noise is measured. This result allows Boltzmann’s constantkBto be measured.
Shot noiseis a measure of the fluctuations observed in certain currents due to the granularity imposed on them by the quantization of charge. In this case Schott’s prediction is that a dc currentidcwill be accompanied by fluctuations obeying another mean-square relation < [i(t)]2> = 2e idcDf. This result allows the magnitude of the fundamental chargeeto be measured.
Noise from either of these sources and many more can be observed because of the modular and user-configurable arrangement of our electronics. The transparent signal-flow layout of our apparatus makes it very clear how noise is quantified in practice since the processes of amplification filtering-in-frequency squaring and averaging-in-time can be understood separately and in detail. The result is a method for quantifying noise and noise densities that students can actually understand. This generates a portable set of skills applicable across the breadth of measurement science.
