Results 201 to 210 of about 76,661 (236)
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IEEE Wireless Communications Letters, 2012
This letter investigates the construction methods of perfect 8-QAM+ sequences, which relate to one of three open problems proposed by Boztas and Parampalli in 2010, and two constructions that transform the known perfect ternary sequences (PTSs) into the required sequences are presented.
Fanxin Zeng +4 more
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This letter investigates the construction methods of perfect 8-QAM+ sequences, which relate to one of three open problems proposed by Boztas and Parampalli in 2010, and two constructions that transform the known perfect ternary sequences (PTSs) into the required sequences are presented.
Fanxin Zeng +4 more
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Capacity/modulation tradeoffs in going from 64 QAM to 256 QAM
IEEE International Conference on Communications, Including Supercomm Technical Sessions, 1990Summary form only given. Increasing the modulation complexity permits significant improvements in bandwidth efficiency. However, the higher level modulation schemes must include additional countermeasures to minimize increased susceptibility to dispersion, loss of threshold, further transmitter power backoff, and increased interference susceptibility. >
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On Impact of Imperfect CSI Over Hexagonal QAM for TAS/MRC-MIMO Cooperative Relay Network
IEEE Communications Letters, 2019In this letter, we investigate the effect of imperfect channel state information (CSI) on quadrature amplitude modulation (QAM) schemes for a multi-input and multi-output (MIMO) variable gain non-regenerative cooperative network over the generalized ...
Parvez Shaik, P. Singya, V. Bhatia
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A Novel Automatic Modulation Classifier Using Graph-Based Constellation Analysis for ${M}$ -ary QAM
IEEE Communications Letters, 2019An innovative automatic modulation classification via graph-based constellation analysis for ${M}$ -ary QAM signals is presented. In our framework, a unified mesh model for the constellation diagrams of the ${M}$ -QAM signals within the modulation ...
Xiao Yan, Guoyu Zhang, Hsiao-Chun Wu
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IEEE Transactions on Circuits and Systems II: Analog and Digital Signal Processing, 2000
A multicarrier quadrature amplitude modulation (QAM) modulator has been developed and implemented with programmable logic devices. The multicarrier QAM modulator contains four CORDIC-based QAM modulators. A conventional QAM modulator needs two multipliers, one adder, and sine/cosine ROM's.
J. Vankka +3 more
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A multicarrier quadrature amplitude modulation (QAM) modulator has been developed and implemented with programmable logic devices. The multicarrier QAM modulator contains four CORDIC-based QAM modulators. A conventional QAM modulator needs two multipliers, one adder, and sine/cosine ROM's.
J. Vankka +3 more
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2001
The block diagram of the conventional QAM modulator is shown in Figure 2.4. The output of the QAM modulator is $$ \begin{gathered} {I_{out}}\left( n \right) = I\left( n \right)\cos \left( {{\omega _{QDDS}}n} \right) + Q\left( n \right)\sin \left( {{\omega _{QDDS}}n} \right) \hfill \\ {Q_{out}}\left( n \right) = Q\left( n \right)\cos \left( {{\omega
Jouko Vankka, Kari Halonen
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The block diagram of the conventional QAM modulator is shown in Figure 2.4. The output of the QAM modulator is $$ \begin{gathered} {I_{out}}\left( n \right) = I\left( n \right)\cos \left( {{\omega _{QDDS}}n} \right) + Q\left( n \right)\sin \left( {{\omega _{QDDS}}n} \right) \hfill \\ {Q_{out}}\left( n \right) = Q\left( n \right)\cos \left( {{\omega
Jouko Vankka, Kari Halonen
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Simplified analysis of QAM BER impairment in hybrid AM/QAM lightwave systems
IEEE Transactions on Communications, 1999A new simplified approach for QAM signal error analysis in hybrid AM/QAM lightwave systems is proposed. The method allows fast and accurate BER calculation.
null Qi Pan, R.J. Green
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1982
Abstract : The objective of this program was to verify the technical feasibility of the variable mode M-ary Quadrature Amplitude Modulation (M-QAM) concepts. Specifically, the adaptive predistortion and baseband equalizer techniques were to be breadboarded and evaluated for M-QAM modes for M = 4, 16, and 64.
null Robert D. +4 more
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Abstract : The objective of this program was to verify the technical feasibility of the variable mode M-ary Quadrature Amplitude Modulation (M-QAM) concepts. Specifically, the adaptive predistortion and baseband equalizer techniques were to be breadboarded and evaluated for M-QAM modes for M = 4, 16, and 64.
null Robert D. +4 more
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Journal of Lightwave Technology, 2019
We propose multilevel coding (MLC) with spatially coupled codes to increase the net coding gain (NCG) and reduce the power consumption of forward error correction (FEC) codes in high-order quadratic-amplitude modulation (QAM) optical transmissions.
Yohei Koganei +4 more
semanticscholar +1 more source
We propose multilevel coding (MLC) with spatially coupled codes to increase the net coding gain (NCG) and reduce the power consumption of forward error correction (FEC) codes in high-order quadratic-amplitude modulation (QAM) optical transmissions.
Yohei Koganei +4 more
semanticscholar +1 more source
2011
This chapter contains sections titled: Constellations for Gaussian Channels General Pulse Shaping Techniques Methods of Generating QAM Methods of Detecting QAM Signals Linearisation of Power Amplifiers Non-differential Coding for Square QAM Differential Coding for Square QAM ...
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This chapter contains sections titled: Constellations for Gaussian Channels General Pulse Shaping Techniques Methods of Generating QAM Methods of Detecting QAM Signals Linearisation of Power Amplifiers Non-differential Coding for Square QAM Differential Coding for Square QAM ...
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