The Experts below are selected from a list of 16716 Experts worldwide ranked by ideXlab platform
Alan E Willner - One of the best experts on this subject based on the ideXlab platform.
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Phase transparent optical data exchange of 40 gbit s differential Phase Shift Keying signals
Optics Letters, 2010Co-Authors: Jian Wang, Zahra Bakhtiari, Scott R Nuccio, Omer F Yilmaz, Alan E WillnerAbstract:We report the Phase-transparent optical data exchange of differential Phase-Shift Keying (DPSK) signals by exploiting the parametric depletion of nondegenerate four-wave mixing (FWM) in a highly nonlinear fiber. Theoretical analyses of nondegenerate FWM involving two signals and two pumps are presented. Analytical solutions are derived, indicating the exchange condition and the feasibility of Phase-transparent data exchange. Optical data exchange between 10.7Gbit/s non-return-to-zero DPSK (NRZ-DPSK) and return-to-zero DPSK signals is implemented with a power penalty of ~1.5 dB at a bit-error rate (BER) of 10−9. Moreover, we demonstrate Phase-transparent optical data exchange between two 40Gbit/s NRZ-DPSK signals with a power penalty of ~4.5 dB at a BER of 10−9.
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optical signal to noise ratio monitoring of an 80 gbits s polarization multiplexed return to zero differential Phase Shift Keying channel
Optics Letters, 2009Co-Authors: Jengyuan Yang, Loukas Paraschis, Lin Zhang, Yang Yue, V R Arbab, A Agarwal, Alan E WillnerAbstract:We propose and experimentally demonstrate an optical signal-to-noise ratio (OSNR) monitoring technique for an 80 Gbits/s polarization-multiplexed return-to-zero differential Phase-Shift Keying channel utilizing a narrowband optical filter and a low-speed detector. A maximum power increment of 19.7 dB is measured at a radio frequency (rf) of 250 MHz for monitoring of OSNR up to 27 dB, insensitive to chromatic dispersion of 0-300 ps/nm and polarization-mode dispersion (PMD) of 0-50 ps.
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self coherent multisymbol detection of optical differential Phase Shift Keying
Journal of Lightwave Technology, 2008Co-Authors: Xiang Liu, Moshe Nazarathy, L Christen, Y K Lize, Alan E WillnerAbstract:This paper treats the recently emerging self-coherent multisymbol decision-feedback-aided detection techniques for optical differential Phase-Shift keyed (DPSK) transmission based on both an optical preprocessing approach and an electronic postprocessing approach. We present in detail i) the generation of a synthetic low Phase-noise effective local oscillator out of the modulated optical data itself, and its estimation theory interpretation; ii) the role of polyPhase (interleaved) DPSK in the optical preprocessing approach in easing the decision feedback realization requirements; iii) detection of M-ary DPSK modulation formats for general M, and differential quadrature Phase-Shift Keying in particular; iv) three alternative integrated-optoelectronic receiver implementations for the optical preprocessing approach detailing the structures of the interferometric front-end and the high-speed electronic analog and digital building blocks; and v) the principle, and alternative implementations, of the digital postprocessing approach to self-coherent detection. We finally compare the capabilities of the emerging self-coherent detection and digital coherent detection techniques.
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monolithic modulator and demodulator of differential quadrature Phase Shift Keying signals based on silicon microrings
Optics Letters, 2008Co-Authors: Lin Zhang, Jengyuan Yang, Muping Song, Raymond G Beausoleil, Alan E WillnerAbstract:Silicon microring resonators are proposed to achieve ultrasmall differential quadrature Phase-Shift Keying modulators and demodulators operated at 20 Gb/s, which may require a dramatically reduced chip size. The modulators are characterized in terms of the carrier transit time and misalignment of the driving signals, while the demodulation performance is analyzed in terms of the bandwidth and frequency detuning of the demodulator. A bit-error rate of <10−9 is achieved using all microring-based devices in the back-to-back case.
Xing Wei - One of the best experts on this subject based on the ideXlab platform.
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Differential Phase-Shift Keying for high spectral efficiency optical transmissions
IEEE Journal of Selected Topics in Quantum Electronics, 2004Co-Authors: Xiang Liu, Xing WeiAbstract:Differential Phase-Shift Keying (DPSK) has attracted significant attentions in research and development during the last several years. An overview of DPSK for high spectral efficiency optical transmission is presented in this paper. The advantages of DPSK in terms of receiver sensitivity and tolerance to fiber nonlinearity will be discussed in detail. A simplified method for estimating the performance of Phase-Shift Keying in numerical simulations is explained. Results of experimental and numerical investigations of several Phase Shift Keying formats, including polarization division multiplexing and multilevel encoding, will be reviewed. Finally, methods for further enhancing performance of Phase-Shift Keying in long-haul transmissions, specifically the compensation of nonlinear Phase jitter, are presented.
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analysis of intrachannel four wave mixing in differential Phase Shift Keying transmission with large dispersion
Optics Letters, 2003Co-Authors: Xing Wei, Xiang LiuAbstract:Intrachannel four-wave mixing (IFWM) in highly dispersed differential Phase-Shift Keying (DPSK) transmission systems is studied with a simple analytical model and numerical simulation. It is found that the IFWM effect in DPSK systems is smaller and less dependent on the bit pattern than in on-off-Keying systems with the same average power. The reduced pulse energy in DPSK and correlation between the nonlinear Phase Shifts of two adjacent pulses contribute to the robustness of DPSK versus IFWM.
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comparison of return to zero differential Phase Shift Keying and on off Keying in long haul dispersion managed transmission
IEEE Photonics Technology Letters, 2003Co-Authors: Xiang Liu, L F Mollenauer, Xing WeiAbstract:Performance of return-to-zero (RZ) differential Phase-Shift Keying (DPSK) in ultralong-haul dense wavelength-division-multiplexing (WDM) dispersion managed transmission is studied experimentally and compared with conventional ON-OFF Keying (OOK) in a 10-Gb/s system. We show that, while OOK out-performs Phase-Shift Keying in a low spectral efficiency WDM system, the performance of DPSK is comparable to OOK at 10-Gb/s transmission with a spectral efficiency of 0.2. Furthermore, RZ DPSK is advantageous in a high spectral efficiency (e.g., >0.4) system and our numerical simulation results show superior performance of DPSK at 10 Gb/s with 25-GHz channel separation.
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Spectral efficiency of coded Phase-Shift Keying for fiber-optic communication
Journal of Lightwave Technology, 2003Co-Authors: Gerhard Kramer, Alexei Ashikhmin, A.j. Van Wijngaarden, Xing WeiAbstract:Several optical modulation and detection schemes are compared by computing their spectral efficiencies over additive white Gaussian noise channels. The bandwidth savings of differential quadrature Phase-Shift Keying (D-QPSK) over both direct-detection on-off Keying and differential binary Phase-Shift Keying suggest that D-QPSK can improve the reach and efficiency of wavelength-division multiplexing systems. To test the theory, Reed-Solomon and low-density parity-check forward error correction codes are designed and evaluated. The codes generally behave as expected, except that for D-QPSK the gains are hampered by the differential detector. It is further shown that neither multiple-symbol differential detection nor decision-feedback detection is attractive when using strong codes.
Xiang Liu - One of the best experts on this subject based on the ideXlab platform.
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self coherent multisymbol detection of optical differential Phase Shift Keying
Journal of Lightwave Technology, 2008Co-Authors: Xiang Liu, Moshe Nazarathy, L Christen, Y K Lize, Alan E WillnerAbstract:This paper treats the recently emerging self-coherent multisymbol decision-feedback-aided detection techniques for optical differential Phase-Shift keyed (DPSK) transmission based on both an optical preprocessing approach and an electronic postprocessing approach. We present in detail i) the generation of a synthetic low Phase-noise effective local oscillator out of the modulated optical data itself, and its estimation theory interpretation; ii) the role of polyPhase (interleaved) DPSK in the optical preprocessing approach in easing the decision feedback realization requirements; iii) detection of M-ary DPSK modulation formats for general M, and differential quadrature Phase-Shift Keying in particular; iv) three alternative integrated-optoelectronic receiver implementations for the optical preprocessing approach detailing the structures of the interferometric front-end and the high-speed electronic analog and digital building blocks; and v) the principle, and alternative implementations, of the digital postprocessing approach to self-coherent detection. We finally compare the capabilities of the emerging self-coherent detection and digital coherent detection techniques.
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Differential Phase-Shift Keying for high spectral efficiency optical transmissions
IEEE Journal of Selected Topics in Quantum Electronics, 2004Co-Authors: Xiang Liu, Xing WeiAbstract:Differential Phase-Shift Keying (DPSK) has attracted significant attentions in research and development during the last several years. An overview of DPSK for high spectral efficiency optical transmission is presented in this paper. The advantages of DPSK in terms of receiver sensitivity and tolerance to fiber nonlinearity will be discussed in detail. A simplified method for estimating the performance of Phase-Shift Keying in numerical simulations is explained. Results of experimental and numerical investigations of several Phase Shift Keying formats, including polarization division multiplexing and multilevel encoding, will be reviewed. Finally, methods for further enhancing performance of Phase-Shift Keying in long-haul transmissions, specifically the compensation of nonlinear Phase jitter, are presented.
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analysis of intrachannel four wave mixing in differential Phase Shift Keying transmission with large dispersion
Optics Letters, 2003Co-Authors: Xing Wei, Xiang LiuAbstract:Intrachannel four-wave mixing (IFWM) in highly dispersed differential Phase-Shift Keying (DPSK) transmission systems is studied with a simple analytical model and numerical simulation. It is found that the IFWM effect in DPSK systems is smaller and less dependent on the bit pattern than in on-off-Keying systems with the same average power. The reduced pulse energy in DPSK and correlation between the nonlinear Phase Shifts of two adjacent pulses contribute to the robustness of DPSK versus IFWM.
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comparison of return to zero differential Phase Shift Keying and on off Keying in long haul dispersion managed transmission
IEEE Photonics Technology Letters, 2003Co-Authors: Xiang Liu, L F Mollenauer, Xing WeiAbstract:Performance of return-to-zero (RZ) differential Phase-Shift Keying (DPSK) in ultralong-haul dense wavelength-division-multiplexing (WDM) dispersion managed transmission is studied experimentally and compared with conventional ON-OFF Keying (OOK) in a 10-Gb/s system. We show that, while OOK out-performs Phase-Shift Keying in a low spectral efficiency WDM system, the performance of DPSK is comparable to OOK at 10-Gb/s transmission with a spectral efficiency of 0.2. Furthermore, RZ DPSK is advantageous in a high spectral efficiency (e.g., >0.4) system and our numerical simulation results show superior performance of DPSK at 10 Gb/s with 25-GHz channel separation.
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Postnonlinearity compensation with data-driven Phase modulators in Phase-Shift Keying transmission.
Optics letters, 2002Co-Authors: Xiang LiuAbstract:A novel scheme for postnonlinearity compensation is proposed to reduce the Phase jitter in Phase-Shift Keying transmission. A Phase modulator is used to modulate the Phase of the data pulses in front of the receiver. The magnitude of the Phase modulation is proportional to the detected pulse intensity, and the sign is opposite to that of the nonlinear Phase Shift caused by self-Phase modulation. Thus, the nonlinear Phase noise induced by amplitude fluctuation and self-Phase modulation is partially compensated for. We show by numerical simulations that a differential Phase-Shift Keying dispersion-managed soliton system at 10 Gbits/s with such postnonlinearity compensation can provide greater than 3 dB of improvement in ultralong-haul dense wavelength-division multiplexing transmissions.
K. Kikuchi - One of the best experts on this subject based on the ideXlab platform.
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investigation of nonlinear impairment effects on optical quadrature Phase Shift Keying signals transmitted through a long haul system
Lasers and Electro-Optics Society Meeting, 2008Co-Authors: K. KikuchiAbstract:We investigate nonlinear impairments of quadrarure Phase-Shift-Keying signals transmitted through a link >1,000 km. The use of the Phase-diversity optical homodyne receiver with digital signal processing enables us to diagnose such transmission impairments clearly.
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demodulation of 320 gbit s optical quadrature Phase Shift Keying signal with digital coherent receiver having time division demultiplexing function
Optical Fiber Communication Conference, 2008Co-Authors: K. Kikuchi, Koji Igarashi, Yojiro Mori, Chao ZhangAbstract:We demodulate a 320-Gbit/s optical quadrature Phase-Shift Keying (QPSK) signal using a novel digital coherent receiver, which features a function of time-division demultiplexing with a local oscillator pulsed at the 10-GHz base-clock frequency.
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coherent demodulation of optical multilevel Phase Shift Keying signals using homodyne detection and digital signal processing
IEEE Photonics Technology Letters, 2006Co-Authors: S Tsukamoto, Kazuhiro Katoh, K. KikuchiAbstract:We demonstrate coherent demodulation of optical multilevel (M-ary) Phase-Shift-Keying (PSK) signals. Since the carrier Phase is estimated accurately through digital signal processing after Phase-diversity homodyne detection, the system performance is highly tolerant to the carrier Phase noise. By off-line bit-error-rate measurements using distributed feedback semiconductor lasers with linewidths of 150 kHz as a transmitter and a local oscillator, it is shown that binary PSK (M=2), quadrature PSK (M=4), and eight-PSK (M=8) signals are successfully demodulated at the symbol rate of 10 Gsymbol/s
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Coherent detection of Phase-Shift Keying signals using digital carrier-Phase estimation
2006 Optical Fiber Communication Conference and the National Fiber Optic Engineers Conference, 2006Co-Authors: K. KikuchiAbstract:We describe a Phase-diversity optical homodyne receiver for demodulating M-array Phase-Shift Keying (PSK) signals, which is based on digital carrier-Phase estimation. Bit-error rate measurements in 2-, 4- and 8-PSK systems are demonstrated with such receiver.
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coherent demodulation of optical 8 Phase Shift Keying signals using homodyne detection and digital signal processing
Optical Fiber Communication Conference, 2006Co-Authors: S Tsukamotor, Kazuhiro Katoh, K. KikuchiAbstract:We demonstrate coherent demodulation of optical 8-Phase Shift-Keying signals for the first time. Since the carrier Phase is estimated accurately through digital signal processing, the system performance is highly tolerant toward the carrier Phase noise.
Chongjin Xie - One of the best experts on this subject based on the ideXlab platform.
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50 gb s silicon quadrature Phase Shift Keying modulator
Optics Express, 2012Co-Authors: Po Dong, Long Chen, Chongjin Xie, L L Buhl, Y.k. ChenAbstract:We report the first successful demonstration of quadrature Phase-Shift Keying (QPSK) modulation using two nested silicon Mach-Zehnder modulators. 50-Gb/s QPSK signal is generated with only 2.7-dB optical signal-to-noise ratio penalties from the theoretical limit at a bit-error ratio of 10(-3). This result validates that silicon photonics could be a viable and powerful platform of photonic integrated circuits in coherent optical communications.
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experimental demonstration of microring quadrature Phase Shift Keying modulators
Optics Letters, 2012Co-Authors: Po Dong, Long Chen, Chongjin Xie, Nicolas K Fontaine, Y.k. ChenAbstract:Advanced 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. Generation of 20 Gb/s QPSK signals is demonstrated with 30 μm radius silicon ring modulators with drive voltages of ~6 V. These compact QPSK modulators may be used in miniature optical transponders for high-capacity optical data links.
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interchannel nonlinearities in coherent polarization division multiplexed quadrature Phase Shift Keying systems
IEEE Photonics Technology Letters, 2009Co-Authors: Chongjin XieAbstract:We study with simulations interchannel nonlinear effects on a 42.8-Gb/s coherent polarization-division-multiplexed quadrature-Phase-Shift-Keying (PDM-QPSK) system with and without dispersion management. We find that interchannel cross-Phase-modulation induced nonlinear polarization scattering can severely degrade the performance of a dispersion-managed PDM-QPSK system. We demonstrate that the time-interleaved return-to-zero PDM-QPSK, where the symbols of the two polarizations are Shifted by half a symbol in time, can significantly suppress the nonlinear polarization scattering in dispersion managed systems, and make systems with inline dispersion-compensation fiber (DCF) achieve better performance than those without DCF.