Assessing Fundamentals of Analog-to-Digital Conversion Using Virtual Experiments in Electrical Engineering

Abstract

Analog-to-digital (AD) conversion is a widely covered topic in Electrical and Electronic Engineering undergraduate programs. To enhance the effectiveness of learning and to engage students in this subject, hands-on activities, such as laboratory experiments, are essential bridging theory and practice. However, it has been observed that many students experience difficulties in learning this topic. One of the reasons is the students’ lack of practical skills in carrying out experimental hardware assemblies and handling instruments. Furthermore, note that the high cost of laboratory teaching infrastructure limits the availability of a sufficient quantity of materials and hardware equipment, especially when it is necessary to accommodate numerous students in practical activities simultaneously. To address these challenges, this study proposes a user-friendly Virtual Instrument (VI) developed in LabVIEW® to enhance the understanding and learning of AD conversion concepts. The VI allows users to select different signal types and configure the AD converter parameters, so the resulting effect of these modifications can be immediately viewed on the student computer screen. Due to its versatility, the computational tool has been applied to Electrical Engineering students at the Escola Politécnica of the Universidade de São Paulo (EPUSP) since 2020. It was first implemented during the social isolation caused by the COVID-19 pandemic and later incorporated into the Electrical Instrumentation course as an additional resource for in-person classes. To evaluate the effectiveness of the VI, an analysis was conducted with 59 students — 29 who exclusively performed the AD conversion experiment using the VI and 30 who used traditional electronics bench infrastructure. The first group achieved a mean grade of 8.78, compared to a mean grade of 7.53 for the control group, which used the laboratory infrastructure. These findings suggest that students using the VI statistically outperformed their counterparts, with an average grade improvement of 16.6%. Therefore, we consider our approach a valuable complementary resource for teaching fundamental AD conversion concepts, with potential for application in other areas of engineering, such as in telecommunications, embedded systems, signal processing, among others.