Abstract
This paper studies the performance of antenna selection for high-speed railway (HSR) distributed antenna systems with imperfect channel state information (CSI). In HSR systems, distributed antennas mounted on top of the train carriage are connected to a mobile relay, which serves as an intermediate node between the base station (BS) and the users inside the train. An important feature of high mobility networks is the fast time-variation of the fading channel caused by the large Doppler spread. It is difficult to accurately estimate, track, and predict the fast time-varying fading coefficients; thus, channel estimation error is usually inevitable and it may seriously degrade system performance. In order to offer a good tradeoff between system performance, cost, and overhead, antenna selection is performed by considering the impacts of both channel estimation errors and noise, such that the antenna with the best link to the BS will be selected to serve users inside the train. The channel estimation error is quantified through the estimation mean squared error (MSE), which is expressed as a closed-form function of the maximum Doppler spread and signal-to-noise ratio (SNR). Several performance metrics, such as outage probability, symbol error rate, spectral efficiency lower bound, and switching rate, are developed as a function of the channel estimation MSE and the geometric layout of the antennas. The analytical and simulation results quantify the significant impacts of imperfect CSI on antenna selection for HSR systems in practical applications.
Highlights
With the increasing popularity of high-speed railway (HSR) systems around the world, it is important to provide broadband reliable wireless communication to passengers onboard high-speed trains
A significant problem, is that radio signals traveling from the base station (BS) into the train are severely attenuated by the vehicular penetration loss (VPL)
This paper addresses the performance of an antenna selection scheme in a distributed antenna setup
Summary
With the increasing popularity of high-speed railway (HSR) systems around the world, it is important to provide broadband reliable wireless communication to passengers onboard high-speed trains. The effect of imperfect CSI on the switching rate, which is an important indicator for selection combining scheme, has not been studied in the literature These existing works only consider traditional multiple-input multiple-output system with co-located antennas, or multiple fixed relays with single antenna, and they do not consider the effects of pathloss or geometric layout of the antenna array, which have significant impacts on the performance of HSR systems. We quantify the performance of the antenna selection system by developing analytical expressions of the outage probability (OP), the symbol error rate (SER), an average spectral efficiency lower bound, and the switching rate They are expressed as explicit functions of a number of system parameters, such as the channel estimation MSE related to the train speed, the average SNR, and the distance between the mobile antennas and the BS. The results are used to develop an analytical OP, SER, a spectral efficiency lower bound, and switching rate for systems operating with imperfect CSI
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: EURASIP Journal on Wireless Communications and Networking
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
