Gamifying Signals : Communications-themed capture the flag for outreach, engagement, and education

Abstract

This article presents and discusses a communications-themed Capture the Flag (CTF) competition designed to enhance visibility and engagement with Electrical and Communications Engineering (ECE). In response to declining enrollments in ECE disciplines worldwide, and in line with pedagogical research advocating for early technical exposure, our initiative leverages Software Defined Radio (SDR) as both a teaching tool and a medium for community building. The CTF features two complementary formats: a virtual edition, designed for technically advanced students and professionals, and an in-person edition, aimed at high-school students and the general public. The virtual challenges are based on recorded IQ signals, requiring participants to decode messages using SDR tools like GNU Radio, guided by appealing narrative clues. The in-person version takes the form of a treasure hunt using live radio signals—initially with SDRs and later simplified to smartphone-accessible signals such as audio, Bluetooth or Wi-Fi. In addition to describing in detail both versions of the CTF, we share pivotal lessons learned in our five years’ experience. During this time, the CTF has grown into a robust educational and outreach platform, fostering a community of SDR practitioners, supporting curriculum development, and motivating students to pursue careers in telecommunications. We are convinced that this kind of hands-on, narrative-driven technical challenges can play a significant role in demystifying complex concepts, stimulating interest in ECE, and bridging gaps between education, industry, and the public.