# On Hybrid MoSK-CSK Modulation based Molecular Communication: Error Rate Performance Analysis using Stochastic Geometry

## TL;DR

This paper introduces a hybrid molecular communication system with multiple transmitters and receivers using different molecule types, employing stochastic geometry for error rate analysis and outperforming existing schemes.

## Contribution

It proposes a novel hybrid modulation scheme with multiple molecule types to eliminate inter-link interference and uses stochastic geometry for analytical error rate performance evaluation.

## Key findings

- Hybrid modulation reduces inter-link interference.
- Analytical error probability expressions derived.
- System outperforms OOK, BCSK, and QCSK schemes.

## Abstract

Data transmission rate in molecular communication systems can be improved by using multiple transmitters and receivers. In molecular multiple-input multiple-output (MIMO) systems which use only single type of molecules, the performance at the destination is limited by inter-symbol interference (ISI), inter-link interference (ILI) and multi-user interference (MUI). This work proposes a new hybrid modulation for a system with multiple transmitters and receivers which uses different types of molecules to eliminate ILI. Further, to enhance the data rate of the proposed system under ISI and MUI, Mary CSK modulation scheme is used between each transmitter-receiver pair. In this paper, the random locations of transmitters present in the three dimensional (3-D) space are modeled as homogeneous Poisson point process (HPPP). Using stochastic geometry tools, analytical expression is derived for the probability of symbol error for the aforementioned scenario. Finally, the performance of the proposed system is compared using the different existing modulation schemes such as on-off keying (OOK), binary concentration shift keying (BCSK) and quadruple concentration shift keying (QCSK) to develop several important insights.