Comparison of localized, interleaved and block-interleaved FDMA in terms of pilot multiplexing and channel estimation

In this paper, DFT-precoded OFDMA is compared in terms of pilot assisted channel estimation in frequency domain for an uplink scenario considering the three different ways of subcarrier allocation: localized, interleaved and block-interleaved. The feasibility of different methods of pilot multiplexing is investigated for the three possibilities, as well as the influence of pilot multiplexing on the Peak-to-Average Power Ratio, the pilot symbol overhead and the channel estimation performance. Further on, the practicability of a post processing algorithm, which is applied to the estimated channel impulse response, is considered for localized, interleaved and block-interleaved subcarrier allocation.