Diffusion-based molecular communications: Inter-symbol interference cancellation and system performance

We first compare the performance of the diffusion-based molecular communication (DMC) systems employing respectively the on-off keying (OOK), whose demodulation depends on a non-zero threshold, and the binary molecular shift keying (BMSK). Our studies demonstrate that the OOK is hard to operate in practical DMC environments, while the BMSK is more feasible for implementation in practice. Furthermore, the BMSK has the embedded capability to cancel some inter-symbol interference (ISI), making it significantly outperform the OOK in terms of the achievable error performance. Then, we propose a low-complexity ISI cancellation (ISIC) approach for further enhancing the performance of the BMSK. We propose two ways for estimating the parameters involved in the ISIC, both of which are demonstrated highly effective. The performance of the ISIC-assisted BMSK is compared with that of the OOK and that of the BMSK without ISIC, showing that the proposed ISIC approach is capable of significantly improving the error performance of the BMSK.