Performance of diffusive molecular communication systems with binary molecular shift keying modulation

The authors analyse and investigate the bit error rate (BER) performance of the diffusive molecular communication (DMC) systems employing binary molecular shift keying (BMoSK) modulation. The DMC systems both without and with inter-symbol interference compression (ISIC) are considered. Specifically, by modelling the number of molecules of one type presenting in a three-dimensional (3D) detection space as a Poisson or Gaussian distributed random variable, they derive the BER expressions of the BMoSK-modulated DMC systems without/with ISIC. However, the strong inter-symbol interference (ISI) present in DMC systems makes the computation of the above-mentioned BER formulas highly involved or even impossible. Therefore, they introduce some simplified approaches, namely the Monte-Carlo and the simplified Poisson (or simplified Gaussian) approaches, to reduce the computation complexity in the cases of long ISI. Furthermore, based on the statistics of decision variables, they analyse the effect of decision threshold on the BER performance. Finally, the BER performance of the BMoSK-modulated DMC systems without/with ISIC is investigated by considering the impact from different aspects, while the different analytical approaches are compared in terms of the accuracy of the BER evaluated based on these approaches.