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An undergraduate design project is described in which a free-space optical communications link is constructed. The interest and motivation for the students is achieved by using a visible laser and constructing a complete system by using the digital output of a CD/DVD player and an audio receiver to transmit music over the free-space link. In addition to providing a high-level technical experience, the project also teaches multidisciplinary teamwork and emulates a real working environment; it is relatively low cost, divisible into modules, and adaptable. An overview of the project is included with representative designs and information. Index Terms--Capstone design, interdisciplinary design, laboratory, optical communications.

A communications systems course laboratory component using an infrared (IR) communication system has been developed as part of the wireless education initiative at the Rose-Hulman Institute of Technology (RHIT), Terre Haute, IN. Students build the system up over several laboratory periods from distinct subsystems, each of which illustrates specific communications concepts. The multiweek laboratory project has the features of being easy to implement on breadboards owing to the low modulation frequency and of being highly motivational to students because of their interest in building a 'working system' with a familiar application. The course, the curricular context, and the laboratory experiments are described, along with student survey data on the perceived effectiveness of the laboratories. The students and instructors have found this laboratory project to be very effective in reinforcing classroom concepts, motivating students, and enhancing debugging skills. Index Terms--Amplitude shift keying, bandpass filters, communication systems, electrical engineering education, infrared (IR) communication systems, light-emitting diodes, optical communication, wireless communication.