A Novel Pre-Equalization Method for Molecular Communication via Diffusion in Nanonetworks

Abstract

In this paper, a novel pre-equzalization method in the context of molecular communication via diffusion (MCvD) is proposed. Our method is based on the emission of two types of messenger molecules (MMs) from the transmitter in order to mitigate the high intersymbol interference (ISI), which critically hinders the performance of any MCvD system. In this approach, the difference between the number of received molecules of each MM type is considered as the actual signal at the receiver side. We model the underlying diffusion channel, and conduct an analysis on the error performance of the proposed method. We compare the proposed method with other modulation and ISI mitigation techniques in the literature, such as concentration shift keying, molecular shift keying, molecular concentration shift keying, and minimum mean squared equalization. Simulation results show that, by tuning the delay value between the emissions of the two MM types and their respective molecule counts, the proposed preequalization method outperforms the aforementioned methods and reduces the bit error rate of the MCvD system significantly.

Simulation Study and Analysis of Diffusive Molecular Communications With an Apertured Plane

“…For an MCvD channel with memory L, theoretical BER evaluation ideally requires 2 L cases' error probability evaluations. Stemming from the complexity of such an operation, various performance metrics including signal-to-interference ratio (SIR) [24], signal-to-interference-and-noise ratio (SINR) [25], and signal-to-interference difference (SID) [15] have been proposed in the literature. Inspired by the existence of a correlation between BER and the ratio between a molecular signal's mean and standard deviation [26], we propose an alternative performance metric to evaluate the signal quality in this work.…”

A vertical channel model of molecular communication and its test-bed

“…The MCvD system [20] is shown in Figure 1. The general processes of MCvD system include Encoding, Sending(Emission), Propagation(Diffusion), Reception(Absorption), and Decoding [6,[21][22][23]. Encoding is the process in which a transmitter node translates information into information molecules that the receiver node can detect.…”

Local Convexity Inspired Low-Complexity Noncoherent Signal Detector for Nanoscale Molecular Communications

“…After accurately acquiring the channel response, a decision-feedback equaliser (DFE) has been proposed [16]. In addition to the aforementioned post-equalisation schemes, a pre-equalisation scheme has also been investigated [20].…”

“…In this work, we propose a simple yet efficient non-coherent detector premised on the local convexity of the diffusion channel response, which may differ dramatically from the common coherent concepts [16], [19], [20]. Note that, rather than a spatial concept, the local convexity in fact refers to the time domain.…”

“…(19)- (20), the threshold γ will be related to three factors: 1) the length of each convexity sub-metric, namely L (recall that each sub-metric is the linear combination of L terms);…”