Investigation of MIMO Channel Characteristics in Tunnel at 1.4725 and 6 GHz

Abstract

In recent years, high-speed railway and subway are being built rapidly in China. Tunnel scenario is a major scenario in some of the high-speed railways and most of the subways. Channel characteristic is the decisive condition of wireless communication system design in tunnel. The availability of multiple-input multiple-output (MIMO) in tunnel is an important issue in the next generation communication network. This paper presents results from a wideband measurement campaign at center frequency of 1.4725 and 6 GHz in a tunnel laboratory. The path loss, root-mean-square delay spread (RMS-DS) characteristics by single-input single-output (SISO) measurement and the angle spread, channel matrix singular values, and MIMO capacity at various link distances by MIMO measurement are illustrated. and these provide insights for MIMO system deployment. And also, the threshold of singular value for channel matrix rank reduction is given.

Channel modeling based on multilayer artificial neural network in metro tunnel environments

“…In another area of potential applications, channel modeling based on ANN has been used for massive multiple-input multiple-output (MIMO) communication systems for the indoor environment [27,28]. Compared to single-input single-output (SISO), MIMO is more sensitive to channel spatial characteristics, which has a significant impact on MIMO communication system performance [48,59,60]. Because the multilayer ANN can provide more accurate prediction of angular spread (AAS or EAS) than single-layer networks, ANNs may be more helpful for the deployment of MIMO communication systems in the tunnel environment.…”