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Applicability of Orthogonal Frequency Division Multiple Access in Satellite Communication
2011 IEEE 73rd Vehicular Technology Conference (VTC Spring), 2011In this paper, we introduce several technologies to adapt orthogonal frequency division multiple access (OFDMA) scheme to satellite environments. Maximizing the commonalities with the terrestrial system is one of the most important factors for cost-effective service delivery, which will finally bring successful deployment of the system.
Hee Wook Kim +5 more
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Interleaved Frequency-Division Multiple-Access
2005In dieser Arbeit wird Interleaved Frequency-Division Multiple-Access (IFDMA) vorgestellt, ein breitbandiges orthogonales Vielfachzugriffsverfahren, das sich besonders für den Einsatz in der Mobilkommunikation eignet. IFDMA besitzt entscheidende Vorteile gegenüber anderen breitbandigen Vielfachzugriffsverfahren für den Mobilfunk.
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Optical frequency division multiple access network design using optical amplifier
[Conference Record] SUPERCOMM/ICC '92 Discovering a New World of Communications, 2003The authors discuss a degradation mechanism involving the optical nonlinearities common in fibers. Particular attention is paid to passive double-star networks (PDSs) employing four wave mixing (FWM), Er-doped fiber amplifiers (EDFAs), and optical frequency division multiplexing (O-FDM).
H. Nakamoto, N. Ohta
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Orthogonal Frequency Division Multiple Access (OFDMA)
2018This chapter presents a brief overview of the OFDMA technique used in 4G WiMAX (Worldwide Interoperability for Microwave Access) and 4G LTE (Long-Term Evolution) cellular system. It is shown that OFDMA is an extension of FDMA, where each frequency band is placed at the null of the adjacent frequency band.
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Block interleaved frequency division multiple access for visible light communications
2017 16th International Conference on Optical Communications and Networks (ICOCN), 2017We propose a power efficient multiple access scheme for visible light communications (VLC) based on the block interleaved frequency division multiple access (B-IFDMA), which provides large frequency-diversity, flexible bandwidth allocation, low complexity of channel equalization and user separation.
Bangjiang Lin +7 more
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Single-Carrier Frequency Division Multiple Access with Anchor-Symbol Insertion
2015 IEEE 82nd Vehicular Technology Conference (VTC2015-Fall), 2015Single-carrier frequency division multiple access with anchor-symbol insertion (ANC-SC-FDMA) is proposed in this paper. Fast sidelobe decaying constraints are developed for both interleaved and localized subcarrier allocation schemes. It is shown that the proposed ANC-SC-FDMA provides much higher spectral compactness than conventional SC-FDMA without ...
Teng-Yuan Chang +2 more
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Channel-independent synchronization of orthogonal frequency division multiple access systems
IEEE Journal on Selected Areas in Communications, 2002We develop synchronization algorithms for both the downlink and the uplink of quasi-synchronous and asynchronous orthogonal frequency division multiple access systems. Unlike existing alternatives, the proposed time- and carrier-offset estimators do not require the transmission of known sequences and exhibit performance independent of the underlying ...
BARBAROSSA, Sergio +2 more
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IEEE Transactions on Vehicular Technology, 1990
A comparison between frequency-division multiple access (FDMA) and code-division multiple access (CDMA) when both methods operate in the mobile satellite communication environment is presented. The mobile satellites under consideration use multiple beams or scan beam antennas and employ frequency reuse of the allocated L-band frequency spectrum ...
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A comparison between frequency-division multiple access (FDMA) and code-division multiple access (CDMA) when both methods operate in the mobile satellite communication environment is presented. The mobile satellites under consideration use multiple beams or scan beam antennas and employ frequency reuse of the allocated L-band frequency spectrum ...
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Identification and classification of Orthogonal Frequency Division Multiple Access signals
2012 6th International Conference on Signal Processing and Communication Systems, 2012This paper proposes a scheme for identification and classification of Orthogonal Frequency Division Multiple Access (OFDMA) signals. Specifically, the cyclostationary pilot signature of an IEEE 802.16e standard compliant waveform is investigated.
Ryan Gray +4 more
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A low‐complexity single‐carrier frequency‐division multiple access transmitter
International Journal of Communication Systems, 2011SUMMARYA framework for a computationally efficient single‐carrier frequency‐division multiple access (SC‐FDMA) transmitter is proposed in this paper. Compared with a wide system bandwidth, the uplink allocation for each user is supposed to be relatively small because of multiple user access, which makes each user's signal vector to be sparse.
Haewoon Nam, Youngok Kim
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