Autoregressive Modeling of Mobile Radio Propagation Channel in Building Ruins

Abstract

This paper addresses an autoregressive (AR) spectral estimation technique adapted for modeling of radio propagation channel in collapsed buildings and urban ruins in the frequency domain. Two mobile communication bands, 900 and 1800 MHz, were investigated. Measured channel frequency responses (CFRs) were firstly modeled by an overestimated AR model. In order to reduce this initial model order, the original CFRs were filtered and decimated. The model order was then optimized using the criteria of the signal-to-noise ratio and the maximum excess delay. According to the different debris structures, antenna polarization and RFs, the final model order was from 3 up to 35. The normalized root mean square error of modeled CFRs was between 0.22-0.38 on average. In order to generate a channel simulator, the statistical distribution functions of the simulator parameters, such as the number, arrival time, and complex amplitude of multipath components, were computed from the AR estimated channel impulse responses. Each of these distributions corresponds to the frequency band, antenna polarization, and ruin structure as well.