R_a~ML~N Wireless Channel Model With The Research On The Implantable Body Area Network

The application of Internet of things in the medical field is an important form that we pay attention to our health gradually.With the the body biological information index transmitting to the hospital or other medical institutions by the implanted chips or wearable devices,we can prevent the disease positively and get online diagnosis or treatment in time.The information's transmitting path from the body to the receiver outside belongs to the domain of non line-of-sight wireless channel,thus finding a suitable wireless channel model which can be used in the indoor implantable body domain communication scenarios is necessary.Yunan University has proposed a RLMN model,R is Rician model,M is the scattering factor added to the Rayleigh model in the form of index.L is Lognormal model and N is the shadowing factor added to the Lognormal model in the form of index.In order to calculate easily,previous researchers divided the RLMN model into RM model and LN model in a scale separation way and estimated the parameters respectively,but failed to get a specific expressions of each parameter.On the basis of the RLMN model,the main work in this paper is as follows:?1?Considering the actual non line-of-sight indoor implantable body domain network measurement,we change the R to the Rayleigh model instead of Rician model and design a R_a^ML^N model which is suitable in the non line-of-sight scenarios and flexible.?2?We calculate the statistical properties in a mathematical method and random function transform way and figure out the probability density function,cumulative distribution function,level crossing rate and the average fading duration.?3?In this paper,we also divided the R_a^ML^N model into R_a^M model and L^N model in a scale separation way.For the R_a^M model,I use the method of Moments estimation to obtain an expression to figure out the scattering factor M and the variance?²_RM.For L^N model,firstly I get two constrained expressions,one is the shadowing factor N with the variance?²_LN,the other one is the shadowing factor N with the mean value?_LN.On this basis,we change the value of N from 0 to 1,using the method of Minimum Mean Squared Error to combine the L^N model's fitting PDF with the PDF of the shadowing data PDF,finally determine the value of N,and then figure out the parameters of the variance and mean value.?4?In this paper,I focus on the application of the R_a^ML^N model in the working frequencyof4.5GHzindoorimplantablewirelessbodyareaactual measurement,using a piece of fresh pork with skin instead of the human body to do the implant measurement,and through comparing the theoretical curves and the simulation curves with the measured data of statistical characteristic curves of R^ML^N model,proving the feasibility of R_a^ML^N model and the application in the indoor implantation domain communication scenarios is adjustable,the derivation and simulation of the statistics properties of R_a^ML^N model is correct...