Results 31 to 40 of about 1,385 (151)
Design, comparative study and analysis of CDMA for different modulation techni
Egyptian Informatics Journal, 2015 In this work, we have design a MIMO–CDMA using 4 ∗ 8 antennas with the combination of MMSE (Minimum Mean square Error Equalizer) for BPSK (Binary Phase shift Keying), QPSK (Quadrature Phase Shift Keying), 16-QAM, 64-QAM and 256-QAM (Quadrature Amplitude ...
Arun Kumar, Manisha Gupta
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Hardware-Efficient Phase Estimation for Digital Coherent Transmission With Star Constellation QAM
IEEE Photonics Journal, 2010 In order to build optical transmission systems for 100 Gb/s and above on a single wavelength division multiplexing channel, transition from quadrature phase-shift keying (QPSK) to higher quadrature amplitude modulation (QAM) formats seems to be ...
Sebastian Hoffmann +6 more
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Effect of Nonlinear Phase Variation in Optical Millimetre Wave Radio over Fibre Systems [PDF]
Journal of Electrical and Computer Engineering Innovations, 2015 In this paper, we propose an optical millimetre wave radio-over-fibre (mm-wave RoF) system that uses a dual drive Mach Zehnder modulator (DD-MZM), which is biased at the maximum transmission biasing point, to generate an optical double sideband ...
A. Bahrami +3 more
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Applied Sciences, 2021 The Gram–Schmidt orthogonalization procedure (GSOP) and Löwdin symmetric orthogonalization procedure (SYOP) are the two mainstream algorithms for the compensation of phase mismatch in an imperfect optical 90° hybrid.
Xueliang Li +4 more
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Performance of Coherent Optical MPSK in Underwater Turbulent Channels With Phase Errors
IEEE Photonics JournalCompared to intensity modulation with direct detection, coherent detection offers superior receiver sensitivity, higher spectral efficiency, and better background noise suppression.
Jiashun Hu +4 more
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Известия высших учебных заведений России: Радиоэлектроника, 2015 Receiving of the broadband phase modulated signal with quadrature phase-shift keying in case of multiple access in-terference and internal Gaussian noise has been considered.
G. S. Nakhmanson, S. V. Kozlov
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Hitless Rate Switching for Dynamically Reconfigurable Optical Systems
IEEE Photonics Journal, 2015 We propose a set of techniques to enable hitless rate switching for reconfigurable optical systems and validate, by computer simulations, their applicability to NRZ, RZ, and Nyquist pulse shapes. The polarization-multiplexed quadrature phase-shift keying
Valery N. Rozental, Darli A. A. Mello
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Quadrature phase shift keying coherent state discrimination via a hybrid receiver
New Journal of Physics, 2012 We propose and experimentally demonstrate a near-optimal discrimination scheme for the quadrature phase shift keying (QPSK) protocol. We show in theory that the performance of our hybrid scheme is superior to the standard scheme—heterodyne detection—for ...
C R Müller +6 more
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Sensors, 2020 The spacecraft tracking telemetering and command (TT&C) system plays an essential role in celestial and terrestrial networks, requiring relative ranging and communication, particularly in satellite formation flying networks and distributed spacecraft ...
Na Zhao +3 more
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IET Communications, 2022 Automatic modulation classification is a task that is essentially required in many intelligent communication systems such as fibre‐optic, next‐generation 5G or 6G systems, cognitive radio as well as multimedia internet‐of‐things networks etc.
Rahim Khan +7 more
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