Research On Propagation Model In Network Planning Of Wireless Private Network

With the rapid development of wireless communication technology and Internet of Things technology,the number of communication equipment in power systems is gradually increasing,and the concept of smart grid emerged.For the power system communication under the smart grid,the traditional wireless propagation model of public network is not well suited for the private network frequency band.This paper studies the correction technology of empirical propagation model and the realization of deterministic propagation model in the private network band.This paper introduces the characteristics of the power wireless private network and the commonly used correction methods and correction process of the outdoor propagation model.Finally,the particle swarm optimization algorithm with inertia weight is used to correct the parameters of the propagation model.According to the model which needs to be corrected,the encoding method of the particles and fitness function in the algorithm are defined,and the optimal solution of the group is found through the interaction between the particles.Compared with the least squares method which commonly used,the particle swarm optimization algorithm transforms the problem of determining the regression coefficient into a function optimization problem,which does not require partial derivative operation and has good applicability.The propagation model corrected by the particle swarm optimization algorithm reduces the data deviation,and the accuracy is further improved.At the same time,the model can better reflect the change law of the data and is more suitable for the actual wireless signal propagation environment.For indoor environments,a deterministic propagation model--the ray tracing model is used for computational analysis.The three-dimensional modeling of the space environment is carried out,and the acceleration effect is achieved by using the methods of space segmentation and virtual source tree.The ray path determination and the calculation of the receiving antenna field strength are completed.In wireless network planning,the computational accuracy and speed of the planning software are critical issues.By comparing and analyzing the influence of reflection and diffraction paths on simulation results under the condition of line-of-sight communication and non-line-of-sight communication,it is concluded that setting the maximum reflection number as 3 and the maximum diffraction number as 1 can achieve the best balance effect of planning software accuracy and rate.