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A Novel Ternary Quadrature Amplitude Modulation
2006 2nd International Conference on Information & Communication Technologies, 2006We propose TQAM (ternary quadrature-amplitude modulation) as a scheme of modulating analog signals to carry ternary digital data. We propose a model for the constellation diagram of the new scheme. Our motivation of thinking about this issue is the fact that the application of multi-value (non-binary) digital signals can provide considerable relief of ...
A.M. Haidar, R. Dernaika, F. Shibani
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Efficient implementation of quadrature amplitude modulation transmitters
Proceedings. IEEE International Multi Topic Conference, 2001. IEEE INMIC 2001. Technology for the 21st Century., 2005Quadrature amplitude modulation (QAM) is widely used in many digital communication systems such as high speed modems. Increasing the data rate by using larger constellations has brought a revolution in digital communication systems. Consequently, there is a need for efficient techniques of implementation of QAM, both in software and the hardware.
F.M. Kashif, W. Qadeer, S.I. Shah
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Differential Encoding for Quadrature-Amplitude Modulation
2010 IEEE 71st Vehicular Technology Conference, 2010In this paper, we propose a novel differential encoder for QAM (quadrature-amplitude modulation), by a look-up table instead of a rule. Using a table for differential encoding has the advantages of both low complexity and good error performance. We propose algorithms to construct the table for maximizing the minimum noncoherent distance and minimizing ...
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Synchrophasor measurement method based on quadrature amplitude modulation
2018 26th Signal Processing and Communications Applications Conference (SIU), 2018Synchrohasor measurement is a common tool to monitor system stability and detect faults in electric power systems and various Phasor Measurement Units (PMUs) have been developed for this purpose. Parameter computation methods of PMUs specifically designed for rapidly time-varying voltage cases caused by nonlinear dynamic loads have been an attractive ...
Ali Gökoğlu +2 more
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Radio-Over-Fibre Broadband Quadrature Amplitude Modulator
2006 European Conference on Optical Communications, 2006A highly-scalable photonic quadrature amplitude modulation architecture based on vector summation and dispersive delay lines, which can generate QAM signals directly from parallel digital words is proposed and experimentally demonstrated by generating a 3 Gbps?8QAM?39 GHz modulated carrier.
M. A. Piqueras +5 more
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Generation of pure electrical quadrature amplitude modulation with photonic vector modulator
Optics Letters, 2008A photonic vector modulator architecture for generating pure quadrature amplitude modulation (QAM) signals is presented. An electrical quadrature-modulated signal at microwave-millimeter-wave frequencies is generated from its corresponding baseband in-phase (I) and quadrature (Q) components.
Juan L, Corral +3 more
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A new hexagonal quadrature amplitude modulation aided media‐based modulation
International Journal of Communication Systems, 2021SummaryIn this paper, a new high‐data rated and energy‐efficient hexagonal quadrature amplitude modulation aided media‐based modulation scheme, called HQAM‐MBM, is proposed for the next‐generation communication systems. In MBM, mirror activation patterns (MAPs) of a reconfigurable antenna have been used to convey extra information in addition to ...
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Optics Letters, 2012
Optical quadrature amplitude modulation (QAM) is experimentally demonstrated with a low-complexity modulator based on a semiconductor optical amplifier and electroabsorption modulator. Flexible amplitude/phase format transmission is achieved. The applicability of octary QAM for coherent optical access networks with sustainable 3 Gb/s per-user bandwidth
Bernhard, Schrenk +6 more
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Optical quadrature amplitude modulation (QAM) is experimentally demonstrated with a low-complexity modulator based on a semiconductor optical amplifier and electroabsorption modulator. Flexible amplitude/phase format transmission is achieved. The applicability of octary QAM for coherent optical access networks with sustainable 3 Gb/s per-user bandwidth
Bernhard, Schrenk +6 more
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Harmonics analysis of power signals using quadrature amplitude modulation
2016 24th Signal Processing and Communication Application Conference (SIU), 2016In this paper, a new method based on quadrature amplitude modulation, which is developed to analyze harmonic spectrum of the voltage and current signals distorted due to nonlinear loads in the power system, is presented. The proposed method aims to reduce the spectral leakage, which occurs in case of oscillations of the fundamental frequency in the ...
Salor, Ozgul, Kibar, Aybuke Esra
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An exact recursive filter for Quadrature Amplitude Modulation dynamics
2008 42nd Asilomar Conference on Signals, Systems and Computers, 2008In certain models for communications signals, such as quadrature amplitude modulation (QAM), circular stochastic processes arise quite naturally. However, much of the literature concerning estimation for communications processes, such as QAM signals, is based upon Cartesian coordinate representations and approximated dynamics, subsequently amenable to ...
Robert J. Elliott, William P. Malcolm
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