Wireless and Digital Communication Systems Research
The Department of Electrical and Computer Engineering (ECE) at Rutgers University has a long history of wireless communications research. In 1989, the school established the Wireless Information Network Laboratory (WINLAB), which focuses on advancing the development of wireless networking technology by combining the resources of government, industry, and academia. Associate Professor Dr. Predrag Spasojevic carried out part of the center’s educational mission to train the next generation of wireless researchers in industry by updating his digital communications graduate courses to incorporate hands-on laboratories and project-based design.
Introducing Tools that Engage Students and Create Interest in Research
Professors at Rutgers observed that students often found it difficult to connect how they could apply theories learned during lecture to real-world applications. For many years, engineering courses used simulations to help students apply theory and gain additional insight on the subject matter. I discovered that more focused, project-based experimentation with real-world signals provided greater insight and gave students the tools they needed to dig deeper and understand why the real-world results did not always provide the same results as the simulation.
I started by introducing my graduate students in the ECE 545 course to the NI USRP-2920 transceiver for the first time in the spring semester of 2012. I introduced my undergraduate students the in the fall semester of 2012. My teaching assistant and I got started by using prewritten labs from the “Digital Wireless Communication: Physical Layer Exploration Lab Using the NI USRP,” by Dr. Robert W. Heath Jr. of The University of Texas at Austin. In addition to experiencing modulation techniques and filtering, our students faced real-life synchronization challenges such as channel estimation and carrier recovery. Every step of the way, we encouraged them to develop critical thinking skills, an understanding, and an intuition for how real-life communication systems worked and how they could be improved through research. I customized the lab experience to reinforce concepts taught in the lecture by using hands-on projects to teach more advanced communication techniques such as the use of Reed-Solomon (RS) codes and Galois fields during channel coding and decoding of a wireless signal.
My students enhanced their understanding by changing algorithms and parameters and seeing results instantly. Everyone was enthusiastic about the course and some students were very motivated. Challenging the graduate students early on is beneficial so that they know how to deal with similar challenges later and have practical knowledge for solving them during their research.
Results After Two Semesters
Students rated the course an average of 4.6 out of 5, which is considered excellent by Rutgers standards, and offered overwhelmingly positive responses:
“I have developed a strong interest in communications. The course was of great standard, offered stimulating thoughts, and was well-supplemented by the labs.”
“In lab assignments, we could really test out the theory and gain a deeper understanding of how communication systems work.”
The initial success of using hands-on equipment extended beyond my ECE 545 course as well. A group of senior undergraduate students learned of the NI USRP-2920 and wanted to use it for their capstone design project. They successfully completed the capstone project using several NI USRP transceivers to form a wireless network of independent nodes acting together to create a wireless orchestra. Undergraduate research students also used the NI USRP-2920 in a project to gain a comprehensive understanding and verify the usefulness of RS coding. Using the NI USRP-2920 to create a real wireless channel helped the students see the effects of additive white Gaussian noise versus burst interference and gain understanding of different coding techniques under various interference conditions.
We achieved impressive productivity with success in a very short time. Because of the success of the course, capstone design project, and research project, I plan to expand the NI USRP platform and NI LabVIEW software platform to both graduate and undergraduate students in future semesters to better prepare and interest students for research work in signal processing, communications, and information theory. The NI USRP platform scales with students as they progress in their studies and move on to research or industry applications, so the knowledge they learn now will transfer with them as they prosper in their careers.
Dr. Predrag Spasojevic