Odor-Based Molecular Communications: State-of-the-Art, Vision, Challenges, and Frontier Directions

Humankind mimics the processes and strategies that nature has perfected and uses them as a model to address its problems. This has led to a new communication technology, molecular communication (MC), using molecules to encode, transmit, and receive information. Despite extensive research, an innate MC method found abundantly in nature-olfactory or odor communication-has not been thoroughly studied using information and communication technologies (ICT). Existing studies focus on digitizing this sense and developing actuators without examining odor-based information coding and MC principles, significantly limiting its application potential. Hence, cross-disciplinary research is needed to uncover the fundamentals of this unconventional communication modality from an ICT perspective. The ways of natural odor MC in nature need to be anatomized and engineered for end-to-end communication among humans and human-made things to enable several multi-sense augmented reality technologies reinforced with olfactory senses for novel applications and solutions in the Internet of Everything (IoE). This paper introduces odor-based molecular communication (OMC) and thoroughly examines olfactory systems, exploring odor communication in nature, including odor information, channels, reception, spatial perception, and cognitive functions. Additionally, a comprehensive comparison of various communication systems sets the foundation for further investigation. By highlighting OMC’s unique characteristics, advantages, and potential applications, this paper lays the groundwork for modeling end-to-end OMC channels, designing OMC transmitters and receivers, and developing innovative OMC techniques.