Analysis And Processing Of Broadband Micropower Wireless Channel Measurement Data

In order to realize intelligent meter reading technology,the grid department needs to use broadband micro-power wireless communication system for data transmission.Therefore,it is necessary to determine the wireless channel model used by wireless communication,thereby introducing broadband micro-power wireless channel measurement research.This thesis discusses and analyzes the characteristics of wireless channel propagation.It focuses on multipath delay estimation algorithm,and builds a wireless channel measurement system for wideband micropower wireless channel measurement,analyzes measurement data and calculates multipath effect parameters.Firstly,this thesis introduces the large-scale fading and small-scale fading characteristics of wireless channels.Besides,describes the shadow effect,multipath effect and Doppler effect of the channel in detail.In addition,proposes the process of obtaining multipath effect parameters and corresponding algorithms and implementation steps are proposed.Secondly,the multipath identification algorithm of wireless channel is studied.It is found that the traditional spread spectrum sliding correlation algorithm can not identify multipath components with non-integer chip interval,and the multipath recognition rate of this algorithm is related to signal bandwidth.Due to the actual channel measurement,the bandwidth of the measurement signal is limited by the hardware platform.Therefore,it is necessary to study high-resolution algorithms that can improve the multipath recognition rate at low bandwidth.There are currently two conventional delay resolution algorithms,which is MODE and WRELAX.Based on this,the improved MODEWREALX algorithm of MODEX-WRELAX algorithm is proposed.The complexity and performance comparison of these three algorithms are carried out under different conditions,and the simulation proves that the MODEX-WREALX algorithm has higher resolution and anti-interference performance than the other two algorithms.Finally,the broadband micropower wireless channel measurement hardware platform is built by using laboratory instruments,which is used to capture the actual wireless channel data,and MODEX-WRELAX algorithm is applied to the measurement data processing to obtain the parameters of the wireless channel parameters.The actual measurement scenarios include indoor corridor line of sight and non-line of sight scenes,outdoor road line of sight and non-line of sight scenes.Then using statistical methods to analyze and synthesize the time delay estimation parameters,and obtain the channel statistical model in these scenarios.The channel model parameters include average additional delay,root mean square delay spread,maximum delay spread and multipath number.Besides,the differences between channel parameters in indoor and outdoor lineof-sight and non-line-of-sight scenarios are analyzed and compared.