Tradeoff Between the Number of Transmitted Molecules and the BER Performance in Molecular Communication between Bionanosensors

In the domain of molecular communication (MC), information is conveyed through the characteristics of molecules transmitted between the transmitter and the receiver bionanosensors via propagation. The constrained size of the transmitter imposes limitations on its storage capacity, constraining the number of available molecules for transmission, with a resulting effect on communication reliability. This paper primarily focuses on achieving an equilibrium between the number of transmitted molecules and the bit error rate (BER) performance. To this end, we first analyze the relationship between the number of transmitted molecules and the BER performance. Subsequently, a balancing function that considers both the number of transmitted molecules and the BER performance is introduced, taking into account the molecules' respective weights. Given the difference in magnitude between the number of transmitted molecules and the BER, these parameters are normalized to facilitate analysis. Subsequently, a Gradient Descent Algorithm is employed to determine the optimal number of transmitted molecules, aiming to achieve the optimal equilibrium in the analyzed MC system. Theoretical and simulation results are provided, substantiating that the optimal outcome indeed establishes an ideal balance between the number of transmitted molecules and the BER.