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Quadrature-quadrature phase-shift keying
IEEE Transactions on Communications, 1989Quadrature-quadrature phase-shift keying (Q/sup 2/PSK) is a spectrally efficient modulation scheme which utilizes available signal space dimensions in a more efficient way than two-dimensional schemes such as QPSK and MSK (minimum-shift keying). It uses two date shaping pulses and two carriers, which are pairwise quadrature in phase, to create a four ...
D. Saha, T.G. Birdsall
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Experimental demonstration of microring quadrature phase-shift keying modulators
Optics Letters, 2012Advanced optical modulation formats are a key technology to increase the capacity of optical communication networks. Mach-Zehnder modulators are typically used to generate various modulation formats. Here, we report the first experimental demonstration of quadrature phase-shift keying (QPSK) modulation using compact microring modulators.
Po, Dong +4 more
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Multipactor in Microwave Transmission Systems Using Quadrature Phase-Shift Keying
IEEE Transactions on Plasma Science, 2010A numerical simulation analysis is made of the effect of signal transmission using the quadrature phase-shift keying of a constant-amplitude RF carrier wave on the initiation of multipactor breakdown in RF devices operating under close-to-vacuum conditions.
V Semenov +5 more
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Optics Letters, 2015
An eight-phase-shift-keying signal is experimentally de-aggregated onto two four-pulse amplitude modulation signals using nonlinear processes in optical elements. Quadrature-phase-shift-keying signals are similarly de-multiplexed into two binary phase shift keying signals by mapping the data points onto the constellation axes.
Morteza, Ziyadi +10 more
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An eight-phase-shift-keying signal is experimentally de-aggregated onto two four-pulse amplitude modulation signals using nonlinear processes in optical elements. Quadrature-phase-shift-keying signals are similarly de-multiplexed into two binary phase shift keying signals by mapping the data points onto the constellation axes.
Morteza, Ziyadi +10 more
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Trellis Coded Quadrature-Quadrature Phase Shift Keying
MILCOM 1987 - IEEE Military Communications Conference - Crisis Communications: The Promise and Reality, 1987Integrated modulation and coding due to Ungerboeck observed no significant effect of dimensionality of signal space on the coding gain; it appeared unlikely that signals in more than two dimensions could have advantages. In this paper, it is pointed out that the utilization of all available signal space dimensions may bring further improvement in the ...
Fei Wang, Jian Liu, Shuai Wang
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Synchronization of quadrature-quadrature phase-shift keying signals
IEEE Transactions on Communications, 1992The key synchronization aspects in the system design of a QQPSK (quadrature-quadrature phase-shift-keying) modem are addressed. The sensitivity of the data demodulator to synchronization errors is discussed, and contextually the performances of some IF and baseband carrier phase and symbol timing recovery schemes are evaluated both theoretically and by
De Gaudenzi, Riccardo, Luise, Marco
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Wideband acoustic communication using quadrature-phase shift keying and eight-phase shift keying
The Journal of the Acoustical Society of America, 2006In JAMSTEC, a short-range (up to 500 m) high-speed acoustic communication system for deep sea environment has been investigating. To widen a bandwidth, the new wideband projector was developed. It consists of two transducer elements and has a toroidal beam pattern.
Hiroshi Ochi +2 more
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Digital coherent quadrature phase-shift-keying (QPSK)
2006 Optical Fiber Communication Conference and the National Fiber Optic Engineers Conference, 2006Conventional coherent detection attempts to synchronize local lasers with transmit lasers indiscriminately without considering individual noise contributors. Handling each contributor properly, we proposed a novel approach for quadrature-phase-shift-keying to enable realization of coherent communication without need of synchronization.
U. Koc, A. Leven, Y. Chen, N. Kaneda
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Continuous phase quadrature phase shift keyed (CPQPSK) signaling technique
MILCOM 88, 21st Century Military Communications - What's Possible?'. Conference record. Military Communications Conference, 2003A continuous phase quadrature-phase-shift-keyed (CPQPSK) modulation technique is presented. This method uses a conventional QPSK-modulated signal and a phase trajectory converter to obtain nearly constant envelope amplitude and continuous phase trajectories. A computer simulation program, MODEM, is used to simulate the CPQPSK signaling technique. It is
S. Kuh, C. Ryan
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