W8EDU is pleased to report four ham-oriented senior projects made possible through the mentorship of Profs. Greg Lee and our own Elmer-in-Chief Prof. Kazdan. See these and other projects at the SOURCE Intersections poster session on April 19th.
Portable Packet Radio Based Location Tracking System
Michael Bowcutt, Department of Electrical Engineering and Computer Science, Michael Codega, Department of Electrical Engineering and Computer Science, William Erickson Department of Electrical Engineering and Computer Science, Professor David Kazdan, Department of Electrical Engineering and Computer Science
The Automatic Packet Reporting System (APRS) is a standard used by amateur radio operators to relay data. Packets, which can contain information such as weather, location, and Internet (TCP/IP) datagrams, can be exchanged point to point among an amateur network. An amateur network may consist of a combination of stations and mobile devices, each of which are identified by their operator’s call sign. A system of mobile APRS nodes could be useful for multi-party location tracking if each node is responsible for transmitting its own location and for retransmitting received locations to the rest of the network, especially in sparse rural areas which might lack cellular network or Internet access. We constructed a mobile APRS device using a Raspberry Pi Zero that is capable of continually transmitting data gathered from peripheral sensors and printing the information in graphical form on a display. We will demonstrate this device using GPS, temperature, pressure, and accelerometer sensors, and we will also establish an audio bus between the development board and a mobile transceiver. This device is designed to work in conjunction with an off-the-shelf amateur radio, expanding on the existing capabilities of that product. Therefore in practice, our product would be cheaper than existing APRS GPS transceivers for those that already use amateur radio.
Helical Antenna Applications
Mercedes Elizalde, Department of Electrical Engineering and Computer Science; Aaron Grgurich, Department of Electrical Engineering and Computer Science; Paul Guativa, Department of Electrical Engineering and Computer Science
The roof of Glennan at CWRU and the NASA Glenn Research Center have line-of-sight propagation, meaning that radio waves will travel in a direct path from the source to the receiver. Line-of-sight propagation is not always an option in RF communications due to Earth’s curvature. However, the Cuyahoga river valley falls in between Glennan at CWRU and the NASA Glenn Research Center, providing a greater line-of-sight than normal for the purposes of this project. Furthermore, the integrated air density between Glennan and NASA is very similar to that of between Earth’s surface and a satellite orbiting the Earth. By establishing line-of-sight communication, the CWRU Amateur Radio Club and Professor David Kazdan can conduct research on weather effects on radio communication. The purpose of Helical Antenna Applications is to provide the CWRU Amateur Radio Club with two low power, high gain helical antennas to be used in their future research and projects. Helical antennas have several advantages over the more common monopole antennas. Since monopole antennas are omnidirectional, more power is required to transmit a signal over large distances. Helical antennas are directional, meaning that they transmit and receive greater power in specific directions, allowing increased performance and reduced interference from unwanted sources. A helical antenna system’s circular polarization also provides a noise-rejection advantage over linear polarization for the proposed research.
Lunar Antenna Control
Sean Liu, Department of Mechanical and Aerospace Engineering; Alex Brandt, Department of Mechanical and Aerospace Engineering
Earth-Moon-Earth (EME) communication is a radio communication technique in which the Moon reflects radio signals transmitted from an Earth-based transmitter back to an Earth-based receiver. This communication technique is highly desirable for amateur radio communication but is difficult to accomplish. Our project is intended to improve, upgrade, and validate an antenna control system used by the Case Amateur Radio Station (W8EDU). This will allow EME communication with a 2-meter antenna. Currently, the system is not implemented within the antenna motor control system. Our project will verify the level of completion and also upgrade the current system to mitigate the challenge of long-distance communication. A feedback control loop will be incorporated into the system to provide better accuracy and easier operation. This system will accurately align the antenna with the moon by utilizing a feedback system via position sensors. Tuning will be accomplished through an investigation into the static and dynamic properties of the 2-meter band antenna. A camera feed will be used to track the moon in its orbit. The ideal result of this project will be complete camera footage proving accurate tracking of the moon. If this cannot be accomplished due to weather conditions, proof of tracking another celestial body will suffice.
ARRL Newsfeed Decoder and Display
Caleb Main, Electrical Engineering; Benjamin March, Electrical Engineering; Benjamin Robinson, Electrical Engineering and Computer Engineering; David Kazdan, Department of Electrical Engineering and Computer Science
The Case Western Reserve University Department of Electrical Engineering and Computer Science lacks an interactive display with which to hook students and touring university guests into exploring a career in electrical engineering. Currently, there exists only static displays outside the Sears Lab in the Glennan building. This project aims to solve that problem by producing an electronic display that shows interested readers news bulletins from the American Radio Relay League station (ARRL). Our work last semester included research of the signal encoding types, which allow the transmission of text over shortwave radio, used by ARRL and established a system to decode their radio news bulletins. Using an amateur radio encoding / decoing software called Fldigi and python libraries, we decoded these messages, corrected the signals for errors caused by noise, and displayed the message in a simple interface. This semester, we continue this project with aims to have the display ready for autonomous operation within the Sears Lab display case. To this end, we are developing a graphical user interface integrating and expanding upon the interface from the previous semester along with a script to automate the process. This new interface will contain the ability to display the most recently decoded message as well as a short history of recent bulletins. This interface will also contain educational information about the decoding process and the technologies in use. Additionally, we are developing an external setup that will allow guests to send a predetermined message over the air. The original setup will receive and decode the message, providing a live demo for guests. Once completed, the Sears Lab display case will have a dynamic exhibit showing the newsfeed broadcasted by the ARRL station. This will provide interested parties with a visible application of an education in electrical engineering.
Dr. Kazdan also served as mentor for the projects “A Method of Recording and Distributing Rehearsal Audio with Conductor Feedback” by Alex Bukovinszky and Tyler Kohrt, and “Sound Reactive LED Cube” by David Fulton, Andrew Riemer, and Michael Ritchey.