Molecular Communication: From Theory to Practice

Always-on, always-available digital communication has changed the world – allowing us to collaborate and share information in ways unimaginable not long ago. Yet many of the physical principles used in everyday digital communication break down as the size of the devices approach micro- or nano-scale dimensions. As a result, tiny devices, with dimensions of microns or less, need to do something different in order to communicate. Moreover, at meter scales there are areas where use of radio signals is not possible or desirable. An emerging biomimetic technique called molecular communication, which relies on chemical signaling is a promising solution to these problems. Although biologists have studied molecular communication extensively, it is very poorly understood from a telecommunication engineering perspective.

Engineering molecular communication systems is important since micro- and nano-scale systems are the key to unlocking a realm of futuristic possibilities such as: self-repairing machines, micro- and nano-scale robotics, synthetic biological devices, nanomedicine, and artificial immune systems that detect and kill cancer cells and pathogens. All these transformative applications have one feature in common: they involve not just single devices working independently, but swarms of devices working in concert. Besides solving the communication problem at small scales, use of molecular communication in areas such as robotics, and infrastructure monitoring can unlock new applications in smart cities and disaster search and rescue.

In this dissertation, after providing a comprehensive survey of the field, two areas of study with high potential impact are identified: on-chip molecular communication, and experimental platforms for molecular communication. First, on-chip molecular communication is investigated towards the goal of networking components within lab-on-chip devices and point-of-care diagnostic devices. This has numerous applications in medicine, environmental monitoring systems, and the food industry. Then in the second part of the dissertation, a tabletop demonstrator for molecular communication is designed and built that could be used for research and experimentation. In particular, no macroscale or microscale molecular communication platform capable of reliably transporting sequential data had existed in the past, and this platform is used to send the world's first text message ("O Canada") using chemical signals.