Radio signal detection and localisation for uncovering unauthorised signals in an examination environment

Abstract

Examination is a fundamental part of education, both for students and institutions. Cheating on exams is something educational institutions are trying to reduce. One form of cheating is the use of a mobile phone to live-stream the exam to pass the test. The goal of this project is to explore the possibility to detect unauthorised communication and locate the signal source. This is done by constructing a system consisting of three Software-defined radios, ADALM-PLUTO, as anchors. A host computer then utilises the signal strength of incoming signals to estimate the distance to its source, and eventually locate the source using a multilateration algorithm. The combined system resulted in the detection of wireless activity on the 2.4 GHz Wi-Fi band, and it could successfully locate the signal source. However, the localisation could not consistently be repeated. We believe that through further development of the system, there are enormous potential benefits for users, that many interested parties can take advantage of.