Research On Channel Capacity Of Diffusion Molecular Communication Model Based On OOK Modulation

The molecular communication model based on OOK(On-Off Keying)modulation is one of the most promising models of nanoscale communication.At present,scholars have limited research on the channel capacity of diffusion molecular communication model based on OOK modulation.Since the released molecules follow the Brownian motion rule in the diffusion-based molecular communication model,ISI(Inter-Symbol Interference)and IUI(Inter-User Interference)inevitably exist.Therefore,how to improve the channel capacity of the system is one of the challenges of molecular communication model research.Based on the above problems,the main work of this paper is as follows:(1)In a point-to-point communication scene that is divided into slots,the ISI of all the time slots in the current time slot is considered,and the optimal decision in the detection process of the receiver nanomachine is obtained by the minimum average error probability criterion threshold,then the mutual information expression of the diffusion-based molecular communication model is obtained,and the channel capacity of the model is analyzed.Simulation results show that different parameters including the distance between two nanomachines,the diffusion coefficient of the biological environment,the duration of each time slot,and the number of time slots have very important influence on the channel capacity.(2)Aiming at the multi-user molecular communication model based on OOK modulation,the ISI and IUI are analyzed,and the optimal decision threshold in the process of receiver nanomachine detection is obtained by the minimum average error probability criterion,therefore the channel capacity is optimized.Finally,the simulations by using MATLAB show the impacts of different parameters on the channel capacity performance of the molecular communication model.The simulation results show that by setting the appropriate prior probability,increasing the diffusion coefficient and the duration of the time slot,and reducing the distance and the number of users between the transmitter nanomachine and the receiver nanomachine,the channel capacity of the molecular communication model based on inter-user interference can be improved and the bit error rate is reduced.(3)Finally,according to the above two different molecular communication models,a visual simulation system is set up.Different parameters can be set in the interactive interface,and the results can be displayed by a visual way,which is convenient for analysis and comparison of the performance of molecular communication models.