On the characteristics of concentration-encoded multi-level amplitude modulated unicast molecular communication

In this paper we have investigated into a multi-level amplitude modulation (M-AM) scheme for concentration encoded unicast molecular communication between a transmitting nanomachine (TN) and a receiving nanomachine (RN) in a nanonetwork. The performance of M-AM scheme has been evaluated on the basis of signal strength in the form of average loss of concentration of received molecules at the location of RN, and interference strength in the form of concentration of undesired molecules that originate at previous symbol but provide additional concentration of molecules over the transmission rate, and interfere with the detection of current symbol. In order to evaluate signal strength and interference strength characteristics two performance metrics have been proposed and explained by observing their behavior as a function of communication range and number of amplitude levels. In addition, results of M-AM scheme have been compared with conventional binary scheme in order to show the corresponding improvement and/or drawbacks when a random sequence of bits is transmitted.