Abstract:

Distance learning in the last three years has necessitated the creation of alternatives that have largely enabled students studying engineering specialties to relatively easily and quickly adapt and promptly learn the not easy theoretical material by using virtual laboratories. In this way, the continuity of the learning process was ensured and at the same time, the teachers expanded their practical and laboratory classes through the application and use of cloud technologies on the one hand and virtual tools on the other.

The possibility of remote access to the relevant laboratory stands and models is a good alternative to training, especially in the situation of a pandemic, in which students can't have a real learning process at the university and on time to carry out real experimental research and analysis.

The authors of this publication examine the fundamentals involved in the construction and implementation of digital filters as virtual instruments. The LabView development environment was used for the development of models of recursive and non-recursive digital filters to study and analyze the main parameters and characteristics of analog and digital signals.

The students' training includes the study of the disciplines of signals and systems and digital signal processing, and in these two disciplines, there are sections related to the digital filtering of signals and their analysis. The study of digital filters provides students with a relatively broad worldview and an idea of their application in practice - high-quality sound processing; suppressing the influence of noises; their use in modern measuring technology; in restoring signals and removing the interference, which in most cases arises from the distortion of the shape of signals and others on the one hand.

On the other hand, students will be able, through the LabView development environment, to explore and analyze the parameters and characteristics of digital signals of modeled digital filters as virtual instruments. In this way, students in engineering majors are given ample opportunities to perform various types of manipulations by changing basic parameters and characteristics and observing the corresponding graphic dependencies. This, on the one hand, develops the skills and competencies of the students, and on the other, creates conditions for developing the creative and intellectual inclination to analyze and create analogies and generalizations.

Also, students can access the given virtual tools at any time, for which they will need an Internet connection and a personal computer or tablet. Providing these access opportunities increases the capacity to conduct more experimental studies and analyze them analytically and graphically on time.

The use of the LabView virtual environment for teaching students from Plovdiv University Paisii Hilendarski, Faculty of Physics and Technology, allows upgrading and expanding the register of functional capabilities by including and embedding additional recursive and non-recursive digital filters.

This sequence of actions - designing, applying digital filters for signal processing, and obtaining data in a different form, provides a good opportunity for students to expand their skills and competencies by interfacing the virtual instruments with other programming environments for additional authentication and verification of the received results.

Keywords:

Filter, recursive, non-recursive, elliptic, Chebyshev, LabView.