Higher Order Derivative-Based Receiver Pre-processing for Molecular Communications

TL;DR

This paper introduces a higher order derivative-based pre-processing technique for molecular communication receivers, effectively reducing inter-symbol interference and improving bit error rate performance by optimizing derivative order.

Contribution

It generalizes time differentiation pre-processing to higher orders, characterizes the trade-off between ISI mitigation and noise, and provides optimization and analysis for threshold and complex detectors.

Findings

Optimal derivative order minimizes BER.

Derivative pre-processing reduces window size for complex detectors.

Numerical results confirm theoretical and performance improvements.

Abstract

While molecular communication via diffusion experiences significant inter-symbol interference (ISI), recent work suggests that ISI can be mitigated via time differentiation pre-processing which achieves pulse narrowing. Herein, the approach is generalized to higher order differentiation. The fundamental trade-off between ISI mitigation and noise amplification is characterized, showing the existence of an optimal derivative order that minimizes the bit error rate (BER). Theoretical analyses of the BER and a signal-to-interference-plus-noise ratio are provided, the derivative order optimization problem is posed and solved for threshold-based detectors. For more complex detectors which exploit a window memory, it is shown that derivative pre-processing can strongly reduce the size of the needed window. Extensive numerical results confirm the accuracy of theoretical derivations, the gains in performance via derivative pre-processing over other methods and the impact of the optimal derivative order. Derivative pre-processing offers a low complexity/high-performance method for reducing ISI at the expense of increased transmission power to reduce noise amplification.