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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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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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2001
For several years, code-division multiple access (CDMA) systems have gained widespread interest in mobile wireless communications. Wideband code division multiple access (WCDMA) [ETSI98] uses a wider channel compared to a narrowband CDMA channel [TIA93], which improves frequency diversity effects and therefore reduces fading problems.
Jouko Vankka, Kari Halonen
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For several years, code-division multiple access (CDMA) systems have gained widespread interest in mobile wireless communications. Wideband code division multiple access (WCDMA) [ETSI98] uses a wider channel compared to a narrowband CDMA channel [TIA93], which improves frequency diversity effects and therefore reduces fading problems.
Jouko Vankka, Kari Halonen
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Experimental Comparison of 64-QAM and Combined Geometric-Probabilistic Shaped 64-QAM
2017 European Conference on Optical Communication (ECOC), 2017We present a novel format of combined geometric-probabilistic shaped QAM constellation. We measure about 1 dB sensitivity gain compared to conventional 64-QAM at 54.2 GBaud and 25% of overhead under different scenarios including back-to-back, single-channel and WDM transmissions.
Fanny Jardel +6 more
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2002
Bandwidth efficient communication systems employ highorder modulation schemes like M-ary QAM modulation for reasons of spectral efficiency. Many sophisticated signal processing algorithms are implemented in a QAM demodulator, including adaptive equalization, timing recovery, carrier recovery, automatic gain control and digital down conversion to name a
Chris Dick, Fred Harris
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Bandwidth efficient communication systems employ highorder modulation schemes like M-ary QAM modulation for reasons of spectral efficiency. Many sophisticated signal processing algorithms are implemented in a QAM demodulator, including adaptive equalization, timing recovery, carrier recovery, automatic gain control and digital down conversion to name a
Chris Dick, Fred Harris
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QAM for terrestrial and cable transmission
IEEE Transactions on Consumer Electronics, 1995We introduce quadrature amplitude modulation (QAM) and discuss QAM architectures used to overcome transmission impairments typically encountered on 6 MHz wide terrestrial and cable TV VHF/UHF channels. The input data to the QAM transmitter is mapped into N bit words called symbols; N determines the QAM level.
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Understanding the error performance of 16-QAM, 32-QAM, 64-QAM, 256-QAM
2020Trinder, Julian, M A Ceng
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