Lab Exercise on Application- and Frequency-Dependent Current Measurement

To prepare future (electrical) engineers for challenges in their professional life, the fundamentals of measurement engineering with the respective sub-aspects are an essential component. This paper describes the design and implementation of a modern laboratory exercise for the precise measurement of small, rapidly changing currents using an example of the varying current consumption of a small micro-controller caused by cryptographic algorithms. Encryption and decryption is implemented for a wireless communication system dedicated for industrial applications to be taught as practical skills embedded into a typical real-world engineering task. To determine measurement uncertainties, the Gaussian error propagation law is employed as described in the Guide to the Expression of Uncertainty in Measurement (GUM). Additionally, students learn about the relationships between signal representation in the time and frequency domain. The paper contains a detailed description of the experimental setup, theoretical knowledge, exemplary measurements as well as experiences and a first evaluation by the students.