Pilot Sequence Design Scheme for Inter-Cell Interference Mitigation in OFDM Systems under Time-Varying Channels
Orthogonal frequency division multiplexing (OFDM) is robust against frequency selective fading due to the increase of the symbol duration. As the symbol duration increases, the OFDM systems become more susceptible to time-variations. Users moving at a quite high speed suffer the inter-carrier interference caused by the time varying (TV) channels. Meanwhile, users at the cell boundary are known to experience a large inter-cell interference in a fully-loaded OFDM cellular environment with a frequency reuse factor equal to 1. In this paper, the design of pilots in the downlink at the cell boundary is addressed, aiming at mitigating the inter-cell interference under TV channel. The properties of these pilots are described, and the simulation results are presented.