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Adaptive Modulation for Orthogonal Frequency Division Multiplexing [PDF]
Engineering and Technology Journal, 2012 Orthogonal frequency division multiplexing (OFDM) is one of the promising technologies to improve the spectral efficiency, enhance system capacity and mitigate inter-symbol interference in the wireless communication system.
Maher K. Mahmood, Abbas Salman Hameed
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Spectrum-Efficient Triple-Layer Hybrid Optical OFDM for IM/DD-Based Optical Wireless Communications [PDF]
, 2020 In this paper, a triple-layer hybrid optical orthogonal frequency division multiplexing (THO-OFDM) for intensity modulation with direct detection (IM/DD) systems with a high spectral efficiency is proposed.
Ghassemlooy, Zabih +5 more
core +2 more sources
Inter Numerology Interference Reduction Using Windowing Technique For OFDM Based Multi-Numerologies
Journal of Applied Science and Engineering, 2022 Cyclic Prefix – Orthogonal Frequency Division Multiplexing is undoubtedly the fundamental waveform for the upcoming wireless standards. Mixed / multi-numerology scheme is one of the promising key features for 5G wireless standard, but it suffers from a ...
P. Kumar, K.R. Usha Rani
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IEEE Wireless Communications Letters, 2018 Orthogonal frequency division multiplexing (OFDM) with index modulation (IM) is a multicarrier transmission technique for frequency-selective fading channels. Although it is energy and spectral efficient, its performance may not be satisfactory as some active subcarriers can be suppressed by fading. In this letter, we consider trellis coded modulation (
Jinho Choi, Youngwook Ko
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Design and Implementation of MC-CDMA Technique Using FPGA [PDF]
Engineering and Technology Journal, 2013 Multicarrier Code Division Multiple Access (MC-CDMA) is attractive technique for high speed wireless data transmission; it's a combination of Orthogonal Frequency Division Multiplexing (OFDM) and Code Division Multiple Access (CDMA).
il A. H. Hadi, Layla Hattim Abood
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A Proposed Channel Estimation Based on Enhanced Sub-carrier Index Modulation and Packet-Discrete Wavelet Transform to Minimize Bit Error Rate [PDF]
Engineering and Technology Journal, 2021 For Orthogonal Frequency Division Multiplexing (OFDM) and other communication systems, many estimating approaches have been developed to estimate the channel state information and lower the Bit Error Rate (BER).
Ansam Jabbar
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A Unified Spectrum Formulation for OFDM, FBMC, and F-OFDM [PDF]
Electronics, 2020 Although orthogonal frequency division multiplexing (OFDM) has been standardized for 5G, filter bank multi-carrier (FBMC) and filtered orthogonal frequency division multiplexing (F-OFDM) remain competitive as candidates for future generations of wireless technologies beyond 5G, due to their reduced spectrum leakage and thus enhanced spectrum efficiency.
Xianzhen Yang +3 more
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EAI Endorsed Transactions on Wireless Spectrum, 2015 This paper considers a cooperative Orthogonal Frequency Division Multiplexing (OFDM)-based cognitive radio network, where the primary system leases a fraction of its subcarriers to the secondary system in exchange for the secondary users (SUs) acting as ...
Yanbo Ma, piming ma, haixia zhang
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A new technique for OFDM: OFDM-index modulation
2013 21st Signal Processing and Communications Applications Conference (SIU), 2013 In this study, a novel scheme called orthogonal frequency division multiplexing with index modulation (OFDM-IM) is proposed for frequency selective channels. In this scheme, the information is conveyed not only by only M-ary signal constellations as in classical OFDM, but also by the indices of the active subcarriers, which are determined according to ...
Basar, Ertuğrul +2 more
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A Low Complexity Optimal LMMSE Channel Estimator for OFDM System
Journal of Communications Software and Systems, 2021 Linear minimum mean square error (LMMSE) is the optimal channel estimator in the mean square error (MSE) perspective, however, it requires matrix inversion with cubic complexity.
Jyoti P. Patra +2 more
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