Research On Encoding Mechanism Of DNA-based Molecular Communication

DNA based molecular communication refers to the use of DNA as information transmission carrier.Similar to molecular communication,it completes information transmission through molecular motion.Owing to the characteristics of high stability,diversity and high density,DNA is an ideal information storage medium,which can improve the low efficiency of molecular communication information transmission.Compared with traditional electromagnetic communication,DNA molecular communication has the characteristics of low energy consumption,biocompatibility and high stability.Therefore,DNA molecular communication system has a wide range of applications in biomedicine,environment,industry,military and other fields.Taking the DNA biological information encoding mechanism as the starting point,combined with the structure design of communication system and the derivation of system channel capacity,the main research contents are as follows:(1)In the diffusion environment,the transmitter of the length information encoding mechanism based on DNA length adopts multi-layer metal foil,the receiver adopts nano pore structure for information decoding,the transmitter adopts OOK(On-Off Keying)modulation,and the length of DNA molecules released in each time slot is different.The effects of molecular diffusion arrival and length recognition on information transmission performance are exhaustively studied.Nanopores recognize the molecular length by monitoring the current blocking time.The probability distribution of length recognition satisfies semi-Gaussian and semi-exponential distribution,then the length recognition error rate is deduced.Based on this communication mechanism,the formula of DNA molecular communication channel capacity is derived.The peak value of information transmission capacity is 0.065 bps,which is 2 times the performance of concentration based molecular communication in the same environment.(2)DNA molecules have many forms of information expression.In this thesis,a multi-information encoding mechanism based on concentration and length is proposed to achieve the effect of transmitting and decoding two bits information in one time slot at the same time.For length information,optimized sub-length pairing is used to achieve the best performance,For the concentration information,the algorithm of adaptively adjusting the concentration decision threshold is adopted,and the decision threshold of the current time slot is determined according to the concentration decision results of the first two time slots,so as to eliminate the inter symbol interference of the concentration information.In the same environment,the performance of multidimensional information coding mechanism system is 80% higher than that of singledimensional length coding system.Three times the signal performance.(3)In the vascular environment,the movement of molecules has the characteristics of higher speed and aggregation.Blood is also an important monitoring way of physical health information,and according to Poiseuille equation,the movement model of molecules in blood can be simulated.Viscosity and pressure difference are important parameters affecting the speed of molecular motion,referring to the preparation of bioliposomes,the dissolution of outer wrapped lipid membrane of DNA also has a significant impact on the information detection process.Through the performance simulation of communication systems in different vascular environments,compared with the diffusion environment,the movement speed of molecules is increased to mm/ s.By dynamically adjusting the time slot length,the information transmission efficiency is increased by 1.5 times compared with the diffusion environment.