Single-carrier modulation with frequency domain processing techniques for ultra wideband channels

In this paper, single-carrier (SC) modulation with frequency domain equalization (FDE) is comprehensively investigated. Maximum achievable information rates of SC systems over ultra wideband (UWB) dense multi-path channels unveil that residual inter-symbol interference (ISI) of FDE results in significant capacity loss. Therefore, we mainly focus on low complexity processing techniques of FDE to reduce residual ISI caused by spectral nulls. For cases of high spectrum efficiency, a time-frequency interleaved (TFI) structure of FDE to achieve high diversity by combining uncorrelated spectral components is proposed. For cases of low spectrum efficiency, a combination of FDE and M-ary bi-orthogonal keying (MBOK) is proposed to eliminate the residual ISI and further improve power efficiency under the measure of E_b/N₀.