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Pilot Structures for the Uplink Single Carrier FDMA Transmission Systems

Single carrier FDMA has been recently considered as a promising uplink transmission scheme for next generation mobile communications due to its low peak-to-average power ratio. Low PAPR characteristic should be maintained not only for data transmission period but also for pilot period. Therefore, the pilot channel should be carefully designed in consideration of low PAPR requirement as well as channel estimation performance and pilot overhead. In this paper, we present a novel time-division multiplexed pilot structure for uplink SC-FDMA systems. The proposed pilot structure can preserve full frequency resolution despite the fact that it is transmitted through a shortened block in the time domain. Consequently, the proposed pilot structure can provide better channel estimation compared to a conventional structure. It is shown through simulations that the proposed pilot structure outperforms conventional methods.