Offline-based clicker using Gaussian frequency shift keying and arduino NRF24L01

The determination of students' proficiency and comprehension has been a struggle for many educational institutions. Response systems, such as clickers, are used to track real-time student response to serve as a justification whether the students understood the topics and concepts that were taught by their instructors or not. The goal of the study is to create an offline-based learning response system that utilizes smartphones as input devices and RF technology as transmission media. The system could gather real-time responses and display its data interpretation by stacked bar graphs. Several trials were made to test the viability of the system in terms of data transmission and reception of information keyed in from the smartphones to the master device attached to a base terminal. Gaussian Frequency-Shift Keying is an effective modulation technique to transmit data in high frequency bands without the interference of Wireless Fidelity. The system is an effective learning response system for offline-based sessions as well as institutions without a stable internet infrastructure. It is scalable in terms of packet transmission as well as sample size of the transmitting devices.