A Statistical Channel Model for 2.4GHz Radio Propagation in Ruins Environment

Abstract

It is of great significance in emergency rescue for earthquake disasters to locate the trapped people using mobile phone Wi-Fi. However, the positioning precision depends on the accuracy of the radio propagation channel model of the ruins environment. In this work, we investigate the channel model in 2.4GHz by measurement in the ruins of Beichuan City, and obtain the parameters of large scale path loss model and delay spread. It is worthy to note that the signal attenuation through ruins is the sum of attenuation through different layered barriers, and the attenuation factors of ferroconcrete and cement brick are 0.72dB/cm and 0.43dB/cm separately. The accuracy of the proposed penetration loss model through ruins is evaluated by the measured data. Moreover, the distribution of RMS delay spread is analyzed according to the cumulative distribution function (CDF) of measured data and evaluated by Kolmogorov-Smirnov (K-S) and Chi-square goodness-of-fit test. The approximation of a linear dependency between mean delay spread and RMS delay spread is also confirmed. This work provides valuable results for the design of mobile Wi-Fi position system in ruins environment.