Development of low-cost radio frequency test equipment

Abstract

This paper focuses on the construction of low-cost radio frequency test equipment which will besubsequently used to conduct performance measurements on a 7 MHz Radio Frequency (RF)transceiver. The transceiver project provides a "Project Based Learning" RF capstone experiencefor students in Electrical and Computer Engineering Technology. The Transceiver Projecttogether with performance testing is structured to support course goals and objectives of "Topicsof RF Communications" offered as a technical elective at the beginning of the senior year. Eachstudent enrolled in the course is required to build and test a complete transceiver system. Students may "team-up" in groups of no more than two students for the purpose of cost sharing, but each student must contribute equally to the building and testing phases of the project. High quality commercial RF test equipment is difficult to obtain and often limits laboratory testing activities. In this paper the author presents low-cost, easy to construct test equipment that partially circumvents this difficulty. In addition to constructing the transceiver a goal of the course is for students to execute a set of test protocols that will extract performance characteristics of the receiver portion of the transceiver. Performance parameters such as noise floor, minimum discernable signal, third-order inter-modulation intercept point, and blocking dynamic range are measured with low-cost test equipment. An additional goal of the project is to prepare students for the upcoming Senior Design Capstone Experience required for a baccalaureate degree in engineering technology. Students are requiredto maintain a detailed project journal to record test results, and experiences throughout the project. To date, student feedback on this project has been very positive and a representative selection of student comments is included in the paper. © 2011 American Society for Engineering Education.