Results 41 to 50 of about 1,385 (151)
Variable‐length balanced codes for quadrature phase shift keyed systems
The Journal of Engineering, 2015 The authors outline an approach to construct capacity‐approaching balanced quadrature phase shift keyed (QPSK) codes. These codes ensure an equal number of different symbol values and many symbol transitions in the encoded sequence in order to assist practical demodulators to accurately recover symbol values.
Xin Tu, Ivan J. Fair
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Design and Performance Analysis of Differential Chaos Shift Keying System With Dual-Index Modulation
IEEE Access, 2019 In order to sufficiently utilize the time slot resources of the recently proposed pulse-position-modulation differential chaos shift keying (PPM-DCSK), we apply dual-index modulation to differential chaos shift keying and then present two differential ...
Xiangming Cai +3 more
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Российский технологический журнал, 2020 The energy and spectral advantages of signals with phase-shift keying predetermined their widespread use in modern digital navigation, communications and television systems.
G. V. Kulikov, Trung Tien Do
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QPSK Modulator with Continuous Phase and Fast Response Based on Phase-Locked Loop [PDF]
Radioengineering, 2017 Among M-phase shift keying (M-PSK) schemes, quadrature phase-shift keying (QPSK) is used most often because of its efficient bandwidth consumption. However, in comparison with minimum-shift keying, which has continuous phase transitions, QPSK requires a ...
L. Kirasamuthranon +2 more
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Engineering Reports, 2022 In this article, a multifunctional optical processing unit for differential eight phase‐shift‐keying (D8PSK) and differential quadrature phase‐shift‐keying (DQPSK) based on four‐wave mixing (FWM) effects in semiconductor optical amplifier (SOA) is ...
Wei Yang, Yafei Wang
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Blind symbol timing offset estimation for offset‐QPSK modulated signals
ETRI Journal, 2019 In this paper, a blind symbol timing offset (STO) estimation method is proposed for offset quadrature phase‐shift keying (OQPSK) modulated signals, which also works for other linearly modulated signals (LMS) such as binary‐PSK, QPSK, π/4‐QPSK, and ...
Sushant Kumar, Sudhan Majhi
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Phase Factor Optimization for QPSK Signals Generated from MZM Based on Optical Carrier Suppression
IEEE Photonics Journal, 2017 We propose and experimentally demonstrate one novel scheme to improve the performance of the vector millimeter-wave (mm-wave) signal generated by intensity modulator based on optical carrier suppression.
Jianjun Yu, Long Chen
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Jurnal EECCIS (Electrics, Electronics, Communications, Controls, Informatics, Systems), 2016 Orthogonal Frequency Division Multiplexing (OFDM) merupakan salah satu alternatif terbaik dalam mengurangi pengaruh lintas jamak pada komunikasi bergerak.
Ali Mustofa, Wahju Adi Priyono
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A Novel Hybrid Cuckoo Search- Extreme Learning Machine Approach for Modulation Classification
IEEE Access, 2019 This paper presents a novel hybrid extreme learning machine (ELM) with cuckoo search algorithm (CSA) for the classification purposes of the digitally modulated signals, such as phase shift keying (PSK), frequency shift keying (FSK), and quadrature ...
Syed Ihtesham Hussain Shah +4 more
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Estimation of BER from Error Vector Magnitude for Optical Coherent Systems
Photonics, 2016 This paper presents the estimation of bit error ratio (BER) from error vector magnitude (EVM) for M-ary quadrature amplitude modulation (QAM) formats in optical coherent systems employing carrier phase recovery with differential decoding to compensate ...
Irshaad Fatadin
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