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Spectrally Efficient Optical Communications
Asia Communications and Photonics Conference 2015, 2015The paper reviews most diffuse techniques used for increasing spectral efficiency in optical communication, considering different network segments. Time-frequency packing will be described, and compared to Nyquist wavelength-division multiplexing and orthogonal frequency-division multiplexing.
POTI', LUCA +3 more
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Spectral Efficiency of Multicarrier CDMA
IEEE Transactions on Information Theory, 2005We analyze the spectral efficiency (sum-rate per subcarrier) of randomly spread synchronous multicarrier code-division multiple access (MC-CDMA) subject to frequency-selective fading in the asymptotic regime of number of users and bandwidth going to infinity with a constant ratio.
Linbo Li +3 more
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Efficient evolutionary spectral clustering
Pattern Recognition Letters, 2016An evolutionary spectral clustering method using a smoothed Laplacian is presented.The incomplete Cholesky decomposition (ICD) reduces runtime from O(N3) to O(N).The memory requirements are decreased from O(N2) to O(N).A stopping criterion using the convergence of cluster assignments is adopted.An efficient procedure to select the number of clusters is
Rocco Langone +2 more
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On the spectral efficiency of constrained FM
IEEE Wireless Communication System Symposium, 2002This paper characterizes constrained FM, CNFM, determines its properties and investigates its spectral efficiency based on the 99 percent bandwidth criteria. Finally, spectral efficiency of CNFM is compared against MSK and duobinary FM. It is shown that CNFM is spectrally more efficient than MSK, but it has the same spectral efficiency as duobinary FM.
D.L. Schilling, K. Shahrabi, R. Alavi
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Spectral Efficiency of Cognitive Radio Systems
IEEE GLOBECOM 2007-2007 IEEE Global Telecommunications Conference, 2007In this contribution, we investigate the idea of using cognitive radio to reuse locally unused spectrum to increase the total system capacity. We consider a multiband/wideband system in which the primary and cognitive users wish to communicate to different receivers, subject to mutual interference and assume that each user knows only his channel and ...
Haddad, Majed +2 more
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energy efficient and spectrally efficient mimo
2019While enabling energy efficiency and spectral efficiency, MIMO systems tends to be associated to an exponential increase of complexity and of signal processing, with the increase of the number of transmit and receive antennas. As described in this article, a reduction of complexity can be obtained with the use of the two proposed algorithms: Maximum ...
Silva, Mário Marques da +2 more
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Spectrally Efficient 1Tb/s Transceivers
Optical Fiber Communication Conference, 2015Based on recent Terabit-class transmission experiment, we discuss the design of 1Tb/s transceivers for long-haul optical systems involving complex tradeoffs between constellation complexity, opto-electronics bandwidth limitations, ROADM cascade, advanced FEC…
Jeremie Renaudier +3 more
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Spectral efficiency in the wideband regime [PDF]
IEEE Transactions on Information Theory, 2002 The tradeoff of spectral efficiency (b/s/Hz) versus energy-per-information bit is the key measure of channel capacity in the wideband power-limited regime. This paper finds the fundamental bandwidth-power tradeoff of a general class of channels in the wideband regime characterized by low, but nonzero, spectral efficiency and energy per bit close to the
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