R_I~M And PLN Channel Model With The Application On The Wireless Body Area Network

The indoor wireless body area network refers to a technology for installing various types of sensors in a specific part of a human body to obtain data related to human vital signs in an indoor situation,and it is an application of the Internet of Things technology on the human body,which can be applied to Real-time monitoring of physical activity indicators or health status of the human body so that people can provide relevant feedback according to the situation.Effective and reasonable modeling of the channel in the indoor wireless body area network is the key to improve the communication quality of the network,and directly affects the research of the physical layer of the wireless body area network.Therefore.,a suitable wireless channel model is established to the wireless body area network channel.Small and medium-scale fading and large-scale fading are necessary to describe.The RLMN model proposed by Yunnan University's Cloud Wireless Access and Heterogeneous Network Engineering Laboratory is a composite model that is more in line with the actual channel fading characteristics,where R represents Rayleigh or Rician distribution,M represents multipath fading factor,and L represents Lognormal model,N Represents a partial shadow fading factor.In this paper,the RM model and the LN model are separated from the RMLN model.The R model is used to represent the RIM model in R model,and the log path loss model is added to the PLN model based on the LN model.The RIM model and PLN are also studied.The model performs derivation of statistical characteristics and parameter estimation.Finally,the RIM model and PLN model are applied to small-scale fading and large-scale fading of indoor wireless body area networks.The main research contents of this paper are as follows:(1)Considering the situation that the partial multipath components in the indoor wireless body network cannot reach the receiving terminal and there may be direct components,this paper separates the R1 model in the RLMN model and considers R as the Rician distribution to study a suitable method.The RIM model of small-scale fading in indoor wireless body network is obtained by adding the multipath fading factor M to the Rician model.Considering that large-scale fading includes both path loss and partial shadow fading,and the future wireless body area network will work at higher frequencies,the path loss in short distances will not be negligible.This paper adds on the LN partial shadow fading model.A digital distance path loss model is developed to study a PLN model suitable for large-scale fading of wireless body area networks.(2)Using the probability density function(PDF)of Rician model,probability density substitution formula,function variable substitution formula and cumulative probability density function(CDF)formula,deducing the first-order statistical properties of RIM model and PLN model PDF and CDF closed-loop expression Then,using the definition of level pass rate(LCR)and mean fading time(AFD),the closed-loop expressions of the second-order statistical properties LCR and AFD of the RIM model and the PLN model are derived.(3)This paper uses the Sum Of Sinusoid method(SOS)to establish the simulation models of RIM model,LN model and PLNmodel respectively,and compares the simulation statistical characteristics of the three simulation models with the theoretical statistical characteristics of the model under different parameters.The correctness of the three simulation models was verified.(4)The maximum likelihood estimation method,the moment estimation method and the parameter separation method are used to estimate the parameters of the RIM model,and the K-S goodness-of-fit test method is used to compare the accuracy of the RIM model parameters estimation for the three parameter estimation methods.Degree,select a more accurate parameter estimation method.The parameters of the PLN model are estimated by the maximum likelihood estimation method and the moment estimation method.A new moment-parameter separation method combining moment estimation method and parameter separation method is proposed to estimate the parameters of LN model.Parameter estimation of RIM model,PLN model and LN model is realized.(5)The vector network analyzer is used to measure the S21 parameters ofthe indoor wireless body area network channel operating at 28 GHz,and the received data is separated into small-scale fading and large-scale fading data by sliding window method,and separated from large-scale fading data.Data on partial shadow fading.Then,the statistical parameters of the RIM model,the PLN model,and the LN model are calculated using the corresponding data.Finally,comparing the statistical characteristics of the measured data,the theoretical and simulated statistical characteristics of the three models,it is proved that the model,the PLN model and the LN model are applied to the correctness of the indoor wireless body area network,and the RIM and PLN models and the similar models are theoretically tested.In contrast,it is verified that the and PLN models are more suitable for small-scale fading and large-scale fading of indoor wireless body networks.