Position-Based Interference Elimination for High-Mobility OFDM Channel Estimation in Multicell Systems

Abstract

Orthogonal frequency-division multiplexing (OFDM) and multi-cell architecture are widely adopted in current high speed train (HST) systems for providing high data rate wireless communications. In this paper, a typical multiantenna OFDM HST communication system with multi-cell architecture is considered, where the inter-carrier interference (ICI) caused by high mobility and multi-cell interference (MCI) are both taken into consideration. By exploiting the train position information, a new position-based interference elimination method is proposed to eliminate both the MCI and ICI for a general basis expansion model (BEM). We show that the MCI and ICI can be completely eliminated by the proposed method to get the ICI-free pilots at each receive antenna. In addition, for the considered multi-cell HST system, we develop a low-complexity compressed channel estimation method and consider the optimal pilot pattern design. Both the proposed interference elimination method and the optimal pilot pattern are robust to the train speed and position, as well as the multi-cell multi-antenna system. Simulation results demonstrate the benefits and robustness of the proposed method in the multi-cell HST system.Index Terms-High speed train (HST), compressed sensing (CS), orthogonal frequency-division multiplexing (OFDM), multicell interference (MCI), inter-carrier interference (ICI).

Block Pilot Based Channel Estimation and High- Accuracy Signal Detection for GSM-OFDM Systems on High-Speed Railways

“…R ECENTLY, wireless communication systems on high speed railways (HSR) attracts a lot of research attention due to wide utilization of mobile terminals [1]- [3]. Existing works are concerned about how to improve the spectral efficiency of the wireless communication systems on HSR [3].…”

“…R ECENTLY, wireless communication systems on high speed railways (HSR) attracts a lot of research attention due to wide utilization of mobile terminals [1]- [3]. Existing works are concerned about how to improve the spectral efficiency of the wireless communication systems on HSR [3]. As a technology of high spectral efficiency exploited by many wireless communication systems, multiple input multiple output (MIMO)-orthogonal frequency-division multiplexing (OFDM) may be difficult to be used in HSR communication systems.…”

Performance Investigation of Angle Differential-QAM Scheme in High Mobility Environments

“…In high mobility scenarios, such as high speed railway, wireless channels vary rapidly due to the high speed movement between transmitter and receiver in complex terrains. The channel exhibits both time selective fading and frequency selective fading [1][2][3] , i.e., doubly selective fading. The doubly selective fading bring serious interferences and severe performance degradation to communication systems [2][3] .…”

“…The channel exhibits both time selective fading and frequency selective fading [1][2][3] , i.e., doubly selective fading. The doubly selective fading bring serious interferences and severe performance degradation to communication systems [2][3] . Therefore, it is valuable to introduce a modulation scheme that make the communication system stable, reliable and efficient in the doubly selective channel.…”

“…It requires coherent demodulation that channel state information (CSI) is employed to correct the distortion of the phase and amplitude at the receiver. However, in high-speed mobile environments, it is hard to get the accurate knowledge of CSI by the conventional channel tracking and estimating methods [2][3] . The imperfect CSI have a significant impact on the performance of QAM and leads to an irreducible bit error ratio (BER) floor [6][7] .…”