This paper proposes a systematic design method of overlap frequency domain equalization(FDE) for single carrier (SC) transmission without a guard interval (GI).Based on the analysis of signal-to-interference-plus-nois...
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This paper proposes a systematic design method of overlap frequency domain equalization(FDE) for single carrier (SC) transmission without a guard interval (GI).Based on the analysis of signal-to-interference-plus-noise ratio (SINR) of the equalizer output for each symbol,the authors adaptivelydetermine the block of the overlap FDE,where the block is defined as a set of symbols at the equalizeroutput with sufficiently low error rate,for a certain fixed sliding window size,which corresponds toa fast Fourier transform (FFT) window *** proposed method takes advantage of the fact thatthe utility part of the equalized signal is localized around the center of the FFT *** addition,the authors also propose to adjust the block size in order to control the computational complexity ofthe equalization per processed sample associating with the average bit error rate (BER) of the *** results show that the proposed scheme can achieve comparable BER performance to theconventional SC-FDE scheme with sufficient GI insertion for both the coded and uncoded cases withvarious modulation levels,while requiring lower computational complexity compared to the SC overlapFDE transmission with the fixed block.
Non-orthogonal multiple access (NOMA) is considered as a prominent multiple access technique for fifth generation (5G) systems mainly because of its high spectral efficiency (SE). NOMA based system employs superpositi...
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Non-orthogonal multiple access (NOMA) is considered as a prominent multiple access technique for fifth generation (5G) systems mainly because of its high spectral efficiency (SE). NOMA based system employs superposition coding (SC) and successive interference cancellation (SIC) at the transmitter and receiver side respectively. Classical multi-carrier NOMA adopts orthogonal frequency division multiplexing (OFDM) as a multi-carrier modulation (MCM) technique;however, high peak to average power ratio (PAPR) and cyclic prefix (CP) inclusion makes OFDM an inadequate choice for NOMA. To improve SE of the OFDM-NOMA, wavelet transform (WT) has been proposed for NOMA. This article proposes new physical layer techniques based on OFDM-NOMA and Wavelet OFDM (WOFDM) -NOMA for tactile internet and investigates their performance in the presence of Gaussian and non-Gaussian channels. overlap frequency domain equalization (OFDE) is proposed as a robust equalization technique to improve the performance of SIC in the presence of Gaussian and non-Gaussian channels for OFDM-NOMA and WOFDM-NOMA. Moreover, to enhance the equalization efficiency of the OFDE, linear precoding (LP) in the form of Walsh Hadamard transform (WHT) is also recommended for OFDM and WOFDM based NOMA transceivers which improves the reliability of the network. Performance of the proposed precoded OFDM-NOMA and precoded WOFDM-NOMA with OFDE is analyzed in the presence of additive white Gaussian noise (AWGN) and impulse noise for Rayleigh fading channel. Link level performance of the presented structures for downlink NOMA is evaluated in terms of bit error rate (BER), PAPR, SE and computational complexity (CC). Furthermore, performance of the proposed architectures is also compared in the presence of impulse noise having different intensities. Simulation results via computer show that the proposed precoded WOFDM-NOMA with OFDE transceiver incorporates low latency through waveform shaping and enhanced reliability throu
Discrete wavelet multitone (DWMT) transceiver was proposed to overcome the problems posed by discrete multitone (DMT) transceiver. DWMT based transceiver has been suggested for digital subscriber loop (xDSL) systems w...
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ISBN:
(纸本)9781467364997
Discrete wavelet multitone (DWMT) transceiver was proposed to overcome the problems posed by discrete multitone (DMT) transceiver. DWMT based transceiver has been suggested for digital subscriber loop (xDSL) systems where crosstalk and impulse noise are the main channel impairments. Modeling of impulse noise is not easy because of its random nature. In this paper, we have discussed all statistical parameters that are required to model the impulse noise necessary for xDSL channel with DWMT transceiver. overlapfrequency division multiplexing (FDE) that has already proposed for DWMT transceiver is applied to equalize the signal. Different trends of bit error rate (BER) for DWMT based transceiver with overlap FDE are also observed with different values of impulse noise index and impulse noise variance. It is concluded that increase in impulse noise density degrades the system's performance.
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