Scattered pilot assisted channel estimation for IFDMA

IFDMA (Interleaved Frequency Division Multiple Access) is the modulation scheme of obtaining frequency diversity gain and establishing frequency orthogonal channel. In multicarrier modulation scheme like orthogonal frequency division multiplexing (OFDM), the pilot signal is dispersive over the frequency domain and the time domain and thus the estimated channel transfer function can trace the fluctuation of the actual one. This pilot signal is referred to scattered pilot. However, there has been no consideration about the scattered pilot for IFDMA. In this paper, we propose scattered pilot signal in IFDMA. The problem of the proposed scattered pilot is enlarging peak to average power ratio of the transmitted signal. We also proposed the three PAPR reduction techniques for the IFDMA symbols including the scattered pilot signal.