Results 171 to 180 of about 1,422 (198)
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Quadrature Demodulation of Binary Phase Shift Keyed Signals
IETE Journal of Education, 1988A quadrature demodulation scheme for Binary Phase Shift Keyed (BPSK) signals is presented. Theory of operation of this demodulator and circuit details for its implementation are given. This technique is useful in systems designed for burst data application requiring fast acquisition such as Time Division Multiple Acces (TDMA), Random Access Descrete ...
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Optical Engineering, 2012
We numerically investigate the nonlinear transmission perfor- mance of 112 Gb∕s coherent transmission systems using polarization multiplexed quadrature-phase-shift-keying (QPSK), offset QPSK (OQPSK) and minimum-shift-keying (MSK) formats, and compare the fiber nonlinear tolerances of the three modulation formats.
Fangzheng Zhang +3 more
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We numerically investigate the nonlinear transmission perfor- mance of 112 Gb∕s coherent transmission systems using polarization multiplexed quadrature-phase-shift-keying (QPSK), offset QPSK (OQPSK) and minimum-shift-keying (MSK) formats, and compare the fiber nonlinear tolerances of the three modulation formats.
Fangzheng Zhang +3 more
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Prefiltered Quadrature Phase-Shift Keying: A Bandwidth- and Power-Efficient Modulation
Journal of Spacecraft and Rockets, 1981Prefiltered quadrature phase-shift keying (QPSK) is a QPSK-type modulation with sin (x)/x pulse shaping. The pulse amplitude shaping is applied strictly for the purpose of shaping the signal spectrum and is discarded at the quadrature demodulator. The data information is carried in the phase of the QPSK modulated signal.
M.U. Chang, M.C. Austin
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Coherent quadrature phase shift keying optical communication systems
Optoelectronics Letters, 2018Coherent optical fiber communications for data rates of 100 Gbit/s and beyond have recently been studied extensively because high sensitivity of coherent receivers could extend the transmission distance. Spectrally efficient modulation techniques such as M-ary phase shift keying (PSK) can be employed for coherent optical links. The integration of multi-
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Heterodyne video transmission with differentially encoded quadrature phase shift keying
Journal of Lightwave Technology, 1992Heterodyne transmission experiments of multiple video channels using differentially encoded quadrature phase shift keying (QPSK) are described. Combining the QPSK microwave modulation format with the subcarrier multiplexing technique results in a total of 20 video channels at 50 Mb/s being transmitted on 10 microwave subcarriers.
R. Gross, R. Olshansky
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Round-robin differential quadrature phase-shift quantum key distribution
Chinese Physics B, 2017Recently, a round-robin differential phase-shift (RRDPS) protocol was proposed [Nature 509, 475 (2014)], in which the amount of leakage is bounded without monitoring the signal disturbance. Introducing states of the phase-encoded Bennett–Brassard 1984 protocol (PE-BB84) to the RRDPS, this paper presents another quantum key distribution protocol called ...
Chun Zhou +5 more
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Offset Generator for Offset Quadrature Phase Shift Keying Modulation
2019The key concept of this paper is development of an Offset generator architecture for Offset Quadrature Phase Shift Keying (OQPSK). Offset generator designed is embedded into QPSK and generates OQPSK modulation. The symbol pattern which the offset generator generates is such that there is only a maximum phase shift of ±90° between the consecutive ...
Alphyn Stanley, R. K. Sharma
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Optimum Receiver Filters in Digital Quadrature Phase-Shift-Keyed Systems with a Nonlinear Repeater
IEEE Transactions on Communications, 1975The effects of filter shaping and nonlinearity in a coherent quadrature phase-shift-keyed (QPSK) system are investigated. Optimization of the receiver filter with respect to the meansquare error (MSE) is considered. Optimization is performed under two different constraints, corresponding to implementation of the filter at intermediate frequency and ...
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From Quadrature-Quadrature Phase-Shift Keying to a New Multicarrier System
Frequenz, 2007Khishigbayar Dushchuluun +2 more
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