Down scaling to the nano-scale in body-centric nano-networks

As Metin Sitti said, small-scale network has a quite bright future, especially in healthcare and bioengineering scenario because the corresponding devices in the network are "unrivalled for accessing into small, highly confined and delicate body sites, where conventional medical devices fall short without an invasive intervention" [1]. Nano-technology has gained a great attention since it was put forward in 1959 [2]. The most fundamental elements to materialize nano-technology are the development of battery-free nano-devices, which can be used to accomplish simple tasks such as computation, sensing, and communication [3]. Furthermore, by combining these basic units, the capacity of these nano-devices could be substantially expanded and much more complex tasks can be targeted, which highlights the concept of nanonetworks. The latter opens the door to an immense range of applications ranging from medical technologies to flexible electronics [4]. On the other hand, researches on body area networks (BAN) at microwave frequencies have obtained great achievements, and it is pointed out by Prof. Metin Sitti that the entire network systems would be shrunk into nano-scale with the nano-robots and molecular machine as the elements in the near future [1]. Additionally, combined with the concept of internet of things, the internet of multi-media nano-things has been introduced and detailed in Reference 5, which indicates the significance of the study of nano-communication. As the name indicates, nano-communication encapsulates the communication between devices at the nano-scale applying novel and modified communication and radio propagation principles in comparison to conventional and existing solutions as further explained in this manuscript [3]. Among three scenarios of body-centric communications, namely: in-body, on-body, and off-body [6], where the in-body application related to medical healthcare is the most promising and of great interest.