Development of Laboratory Assignments for Teaching Communication Systems

Department of Electrical Engineering and Renewable Energy, Oregon Institute of Technology Abstract The high-cost of specialized radio test equipment, like spectrum analyzers and signal generators, presents a challenge to universities offering undergraduate communication systems engineering courses with large class sizes. Many universities either lack laboratory sections or offer limited laboratory assignments that focus on exploring individual concepts. As a result, current practice in teaching classes on communication systems typically rely on involved mathematical calculations and simulations. Students completing these classes may have a general understanding of analog and digital signal processing, but frequently lack hands-on experience in applying these concepts to build functional communication systems. In recent years, affordable software-defined radio (SDR) platforms and open source software like GNU Radio have been developed by the research and hobbyist communities. The main idea of SDR is to use an analog-to-digital converter to sample radio signals and perform most signal processing in the digital domain using a computer (as opposed to using traditional hardware components like mixers and amplifier.) This technology is flexible, convenient, and offers similar capabilities as specialized radio test equipment, but at a fraction of the cost. Similar to SDR, the recent expansion of inexpensive transceivers and home network devices offer new possibilities for applied projects in the classroom. We are developing a series of laboratory assignments for a senior-level Electrical Engineering course in communication systems that leverage the advantages of inexpensive tools like SDR, low-power transceivers and small home network devices. These experiments allow students to transmit and receive live radio systems to directly explore basic concepts like modulation, synchronization, filtering, and noise. By allowing students to build and test functioning radio system and small smart-device networks, students are able to gain a broader understanding of how communication systems work as opposed to the often piecemeal topic coverage in traditional classes. Using live signals also allows for a natural discussion of related topics such as FCC rules, antennas and signal propagation. Although still a work in progress, initial student response to this laboratory content has been positive