An Adaptive DFT-SOFDM for Future Cellular Systems

Orthogonal frequency division multiple access (OFDMA) is a promising multiple access technique. DFT-SOFDM, which combines OFDMA with SC-FDE, is being proposed for 3GPP LTE. Based on the concept of optimal signal subspace (OSS), we propose an adaptive DFT-SOFDM, namely OSS-DFT-SOFDM in this paper. The proposed adaptive algorithm ensures that the fluctuation range of the received SNR after equalization is small. Compared with conventional OFDMA and DFT-SOFDM, simulation results show that the proposed system considerably improves performance. The algorithm adopts uniform constellation and equal power allocation among usable subcarriers. So, the proposed system is suitable for broadband mobile wireless communication because both the complexity and the overhead of the adaptive system are considerably low