A Receiver Design for Molecule Shift Keying Modulation in Diffusion-Based Molecular Communications

In this paper, the receiver design for Molecular Shift Keying (MoSK) modulation is studied to recover the transmitted sequence distorted by inter-symbol interference (ISI) in diffusion-based molecular communications. Firstly, the receiver design based on the maximum likelihood detection is discussed, which is based on the arrival time of the molecules at the receiver. Considering the implementability, the method of Maximum Likelihood Detection with Overlapping Segmentation (MLDOS) is proposed. Compared with the direct demodulation scheme which is based on the arrival order of received molecules, numerical results show that the bit error ratio (BER) performance of MLDOS is significantly better when the channel is severely impacted by ISI. Then a simple method called Simplified Mapping Detection (SMD) method is derived to reduce the computational complexity. The simulation results show that the BER performance of SMD, which has relatively lower time complexity, is nearly the same as that of MLDOS.