Morse Code Decoder using Finite State Automata

Morse code remains a practical mode of communication in constrained or low-bandwidth environments. However, traditional decoding systems often lack adaptability, scalability, and educational integration. This paper proposes a hybrid Morse code decoding framework that integrates Finite State Automata (FSA) for real-time deterministic decoding and Pushdown Automata (PDA) for handling complex, nested input structures using stack memory. Developed in Python with a Tkinter-based graphical user interface, the system enables users to visualize automata transitions, stack operations, and the decoding process interactively. The decoder achieves over 98.5% accuracy across benchmark Morse sequences, with average decoding times of 12–19 ms per message. Time complexity is maintained at O(n), with space complexity ranging from O(1) to O(n). Experimental results validate the system’s robustness and efficiency, while its visual interactivity enhances understanding of formal language concepts. By bridging the gap between theoretical computation models and practical decoding tasks, the system provides both functional utility and pedagogical value for learners and developers.