Spectrally Efficient Frame Format-Aided Turbo Equalization with Channel Estimation (original) (raw)
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To date most frequency-domain (FD) turbo equalization schemes assume ideal channel state information (CSI) is available. In this paper, a system combining FD turbo linear equalization with time-domain channel estimation is developed and evaluated for single-carrier modulation formats. The effect of estimated CSI on the equalizer form is shown. Performance results employing convolutionally encoded QPSK and 16-QAM transmissions show the efficacy of the proposed system and its capability to operate in different wireless scenarios.
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2017 IEEE 28th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC), 2017
Multiuser (MU)-multiple-input multipleoutput (MIMO) receivers often need to take iterative strategies to cancel multiuser-interference (MUI). Frequency domain turbo equalization is one of the most promising solutions to the MUI problem. It offers a reasonable trade-off between the receiver performance and the computational complexity by assuming cyclic prefix (CP)-transmission. Nevertheless, CP-transmission is not preferable for the battery life of user terminals. Therefore, this paper proposes a new frequency domain multiuser-detection (MUD) technique by extending the chained turbo equalization (CHATUE) to MU-MIMO systems. Simulation results verify that the proposed MU-MIMO CHATUE algorithm is a more reliable option to improve the spectral-and/or energy-efficiency by eliminating the necessity of CP-transmission than by shortening the training sequences or puncturing the coded data bits. Index Terms-Spectral efficiency, multiuser interference (MUI), cyclic prefix (CP), overlap-and-add.
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