Enhanced Rate Division Multiple Access for Electromagnetic Nanonetworks

An electromagnetic (EM) nanonetowork is considered to be a key technology in realizing Internet of Nano-Things. However, the traditional communication schemes cannot be directly applied at nanoscale level due to extreme limitation in energy, memory, computational resources, and hardware designs. Due to unique properties of pulse-based communication in nanonetoworks, rate division time-spread ON-OFF keying is considered to be appropriate modulation and channel access mechanism. As such, a symbol in EM nanonetwork would be is represented by either a single pulse or absence of pulse. In rate division, the symbol streams transmitted by multiple users are interleaved by assigning different time periods between two symbols of each user referred as symbol interval. The symbol interval is required to be derived from prime or coprime numbers to minimize the number of collisions. In this paper, we propose a scheme to derive the symbol interval by generating unique prime number at each user node using Prime Mod algorithm. Our scheme do not require coordination between transmitter and receiver and it can be easily implemented in both infrastructure based and ad hoc nanonetworks. Moreover, we show the statistical properties of the computed prime numbers, bounds on prime numbers that can be used, collision probability, and comparison of computational complexity with conventional schemes.