Hakseong Kim

Inter-cell interference management using multi-cell Shared Relay Nodes in 3GPP LTE-Advanced networks

In this paper, we propose an inter-cell interference management scheme using a multi-cell SRN (Shared Relay Node) in order to avoid inter-cell interference and to increase the cell throughput in 3GPP LTE (3rd Generation Partnership Project Long Term Evolution)-Advanced networks. Recently, the CoMP (Coordinated Multi-Point transmission/reception) scheme has received growing attention as a promising scheme for overcoming the inter-cell interference in 3GPP LTE-Advanced networks. In practice, however, when feedback delays and channel estimation errors are considered, the performance of the CoMP scheme may severely degrade. The objective of this paper is to present a new SRN architecture located at the neighboring area of adjacent cells so as to manage the inter-cell interference. The SRN can overhear control signals transmitted by adjacent eNBs (enhanced Node-B) and UEs (User Equipments). Based on the overheard information, the SRN not only performs data retransmission as a usual type II relay but also manages the inter-cell interference. In particular, we suggest a resource allocation scheme and a power control scheme assisted on the SRN for effective interference avoidance, and evaluate their performances through simulations.

Performance analysis of an open loop transmit diversity for Rician multipath wideband CDMA channels

Analyzes the performance of a simple open loop transmit diversity (TD) scheme proposed by the authors for wideband CDMA systems under Rician multipath fading channels. In particular, the probability density function (pdf) of the output signal-to-noise ratio (SNR) and the uncoded bit error rate (BER) are derived. Numerical results show that the scheme with low complexity outperforms open loop space-time transmit diversity (STTD), and achieves a close performance to ideal closed loop transmit adaptive array (TxAA) in typical Rician multipath fading channels.