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MSK and Offset QPSK Modulation
IEEE Transactions on Communications, 1976Minimum shift keying (MSK) and offset keyed quadrature phase shift keying (OK-QPSK) modulation techniques are often proposed for use on nonlinear, severely band-limited communication channels because both techniques retain low sidelobe levels on such channels, while allowing efficient detection performance. A more detailed performance comparison of the
Steven A. Gronemeyer, Alan L. McBride
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Collision of QPSK Modulated Solitons
Optical Fiber Communication Conference, 2016We study an isolated soliton collision of two QPSK modulated 1st order solitons having 12GHz frequency offset in simulation and experiment. Separate and joint NFT is applied to the received signals to show effects of the collision.
Karsten Schuh +3 more
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Common detectors for shaped offset QPSK (SOQPSK) and Feher-patented QPSK (FQPSK)
GLOBECOM '05. IEEE Global Telecommunications Conference, 2005., 2005Symbol-by-symbol detection of SOQPSK and FQPSK using detectors designed for offset QPSK represents a simple common detector architecture for these two interoperable waveforms. Unfortunately, this detection method results in a 2 dB loss in bit error rate performance.
Tom Nelson, Erik Perrins, Michael Rice
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Equalization for unbalanced QPSK and for staggered QPSK
Proceedings of GLOBECOM '93. IEEE Global Telecommunications Conference, 2002Linear transversal filter equalization for an unbalanced QPSK signal is studied, and optimum tap gains (which minimize MSE) for the two required equalizers are found as solutions to a new set of equations. The equalizers are chosen to have a fractional tap spacing of one half.
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2011 IEEE 9th International Symposium on Intelligent Systems and Informatics, 2011
The paper presents the theoretical backgrounds of a QPSK Modulation. The QPSK Modulator is then simulated using Matlab/ Simulink environment and System Generator, a tool from Xilinx used for FPGA design as well as implemented on a Spartan 3E Starter Kit board. The modulator algorithm has been implemented on FPGA using the VHDL language on Xilinx ISE 12.
S.O. Popescu, A.S. Gontean, D. Ianchis
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The paper presents the theoretical backgrounds of a QPSK Modulation. The QPSK Modulator is then simulated using Matlab/ Simulink environment and System Generator, a tool from Xilinx used for FPGA design as well as implemented on a Spartan 3E Starter Kit board. The modulator algorithm has been implemented on FPGA using the VHDL language on Xilinx ISE 12.
S.O. Popescu, A.S. Gontean, D. Ianchis
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2014 IEEE International Conference on Advanced Communications, Control and Computing Technologies, 2014
QPSK is a modulation scheme used to represent digital data. Any modulation scheme uses finite number of different signals to represent digital data. QPSK uses four different phases to represent data. QPSK (Quadrature Phase Shift Keying) scheme is used in various applications in modern digital communication system; it provides high performance on ...
Nakul Birla +3 more
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QPSK is a modulation scheme used to represent digital data. Any modulation scheme uses finite number of different signals to represent digital data. QPSK uses four different phases to represent data. QPSK (Quadrature Phase Shift Keying) scheme is used in various applications in modern digital communication system; it provides high performance on ...
Nakul Birla +3 more
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Adaptive ZCDPLL for QPSK detection
2005 12th IEEE International Conference on Electronics, Circuits and Systems, 2005A Second Order Zero Crossing Digital Phase Locked LOOP (ZCDPLL) with time varying loop gains is applied to QPSK detection. The ZCDPLL consists of an adaptive Kalman estimator which estimates the phase offsets of a received data bearing passband signal. The ZCDPLL digital filter gains are updated using the Recursive Least Squares (RLS) algorithm.
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ACE-QPSK: a new method of coding QPSK for the nonlinear transmitter
Proceedings of IEEE Singapore International Conference on Networks/International Conference on Information Engineering '93, 2002Band-limited QPSK signals are prone to a high degree of spectral regrowth when nonlinearity is present in the transmitter amplifier. In a multi-carrier application with close adjacent channels (such as an FDMA satellite system), the spectral regrowth of adjacent channels can result in severe interference with the desired carrier.
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Integrated Components for Optical QPSK Transmission
Frontiers in Optics, 2006LiNbO3 Z-cut QPSK modulators, LiNbO3 90° hybrids co-packaged with balanced photoreceiver OEICs and SiGe/CMOS circuits for digital signal processing are being developed as key components for a 40-Gb/s synchronous QPSK polarization division multiplex transmission testbed.
Noé, Reinhold +4 more
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Speckle-based BPSK/QPSK demodulator
Optical Fiber Communication Conference (OFC) 2019, 2019BPSK and QPSK RF signals are demodulated without carrier frequency knowledge. The demodulator employs compressive sensing recovery methods and uses speckle within a multimode fiber to perform the requisite random signal projections.
Adam C. Scofield +4 more
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