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An experiment of PMD compensation in 40-Gb/s PSBT transmission system
Feng Tian, Lixia Xi, Xiaoguang Zhang, Xuan Weng... and Qianjin Xiong|Show fewer author(s)
An adaptive polarization mode dispersion (PMD) compensation experiment is reported in a 40-Gb/s phase shaped binary transmission (PSBT) communication system, with the use of a new digital signal processor (DSP)-based optical PMD compensator. PMD tolerance is found to be enhanced by 8 ps after PMD compensation with 1-dBAn adaptive polarization mode dispersion (PMD) compensation experiment is reported in a 40-Gb/s phase shaped binary transmission (PSBT) communication system, with the use of a new digital signal processor (DSP)-based optical PMD compensator. PMD tolerance is found to be enhanced by 8 ps after PMD compensation with 1-dB optical signal-to-noise ratio (OSNR) penalty. Under the condition of fast change of states of polarization up to 85 rad/s in the fiber link, the performance of our PMD compensator undergoes the bit error ratio (BER) test for as long as 10 h..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 816 (2010)
Heterodyne direct-detection OOFDM system with low sampling rate
Lin Cheng, He Wen, Xiaoping Zheng, Hanyi Zhang, and Yili Guo
A method of multi-channel receiving for high bit rate heterodyne direct-detection optical orthogonal frequency-division-multiplexing (OOFDM) system is proposed to reduce the sampling rate demand of analog-to-digital converter (ADC). The sampling rate of ADCs can be reduced to 1/N that of the original signal bandwidth iA method of multi-channel receiving for high bit rate heterodyne direct-detection optical orthogonal frequency-division-multiplexing (OOFDM) system is proposed to reduce the sampling rate demand of analog-to-digital converter (ADC). The sampling rate of ADCs can be reduced to 1/N that of the original signal bandwidth in an N-channel receiving system. Aided by a succeeding digital signal processing (DSP) at the receiver, aliasing free signal can be recovered. A back-to-back experimental result is given for a 4-channel system, based on which, a down conversion process for heterodyne can be reduced. The signal rebuilding algorithm is given and analyzed in its complexity and noise tolerance..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 819 (2010)
Novel schemes to generate multi-level modulation formats for ultra-capacity coherent detection transmission systems (Invited Paper)
Jianjun Yu, and Xiang Zhou
We summarize several novel schemes to generate multi-level modulation formats for high capacity transmission system with high spectral efficiency. We show that multi-level 8QAM, 16QAM, 32QAM, and 64QAM (QAM: quatlrature amplitude modulation) optical signals can be generated by commercial optical and electrical devices.We summarize several novel schemes to generate multi-level modulation formats for high capacity transmission system with high spectral efficiency. We show that multi-level 8QAM, 16QAM, 32QAM, and 64QAM (QAM: quatlrature amplitude modulation) optical signals can be generated by commercial optical and electrical devices. Employing these multilevel modulation formats, we have realized PDM-8QAM (PDM: polarization division multiplexing) 32 Tb/s and PDM-36QAM 64-Tb/s signals transmission over 580- and 320-km fibers, respectively..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 823 (2010)
100-Gb/s undersea transmission with high spectral eff iciency using pre-filtered QPSK modulation format (Invited Paper)
J.-X. Cai, Y. Cai, C. R. Davidson, D. G. Foursa... and Neal S. Bergano|Show fewer author(s)
We provide a review of our recent 100-Gb/s, high spectral efficiency (SE) experiment targeting transoceanic and regional undersea transmission distances. We demonstrated that simple pre-filtering at the transmitter together with a maximum a posteriori probability (MAP) detection algorithm can significantly improve SE. We provide a review of our recent 100-Gb/s, high spectral efficiency (SE) experiment targeting transoceanic and regional undersea transmission distances. We demonstrated that simple pre-filtering at the transmitter together with a maximum a posteriori probability (MAP) detection algorithm can significantly improve SE. We transmitted 96×100-Gb/s pre-filtered polarization division multiplexed return-to-zero quadrature phase shift keyed (PDM-RZ-QPSK) channels with 300% SE over 10608 km using 52-km spans of 150-μm2 fiber and simple single-stage erbium-doped fiber amplifiers (EDFAs). We also achieved 400% SE over 4368 km using similar techniques..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 831 (2010)
High speed optical transmission utilizing constant envelope modulation based on frequency shift keying and minimum-shift keying (Invited Paper)
Nan Chi, Wuliang Fang, Yufeng Shao, Junwen Zhang... and Li Tao|Show fewer author(s)
A novel 40-Gb/s constant envelope optical frequency shift keying (FSK) transmitter and the transmission characteristics are investigated both by simulation and experiment. Meanwhile, to increase the spectrum efficiency of FSK, we propose a novel optical minimum-shift keying (MSK) scheme and analyze its performance compA novel 40-Gb/s constant envelope optical frequency shift keying (FSK) transmitter and the transmission characteristics are investigated both by simulation and experiment. Meanwhile, to increase the spectrum efficiency of FSK, we propose a novel optical minimum-shift keying (MSK) scheme and analyze its performance compared with other MSK schemes and other traditional modulation formats. Simulation and experimental results show that the novel FSK scheme could be a potential candidate for the future high speed transmission and label switching systems. And the novel MSK scheme deserves future deep research for its potential excellent performance..
Chinese Optics Letters
- Publication Date: Jul. 08, 2021
- Vol. 8, Issue 9, 837 (2010)
Nonlinear polarization ef fects and mitigation in polarization-division-multiplexed coherent transmission systems (Invited Paper)
Chongjin Xie
Using numerical simulations, the nonlinear transmission performance of polarization-division-multiplexed quadrature-phase-shift-keying (PDM-QPSK) coherent systems is studied. It is found that inter-channel cross-polarization modulation (XPolM) induced nonlinear polarization scattering can significantly degrade the tranUsing numerical simulations, the nonlinear transmission performance of polarization-division-multiplexed quadrature-phase-shift-keying (PDM-QPSK) coherent systems is studied. It is found that inter-channel cross-polarization modulation (XPolM) induced nonlinear polarization scattering can significantly degrade the transmission performance of PDM-QPSK coherent systems and change the perspective of dispersion management in optical coherent transmission systems. Some techniques to mitigate nonlinear polarization scattering in dispersion-managed PDM coherent transmission systems are discussed, including the use of time-interleaved return-to-zero (RZ) PDM formats, the use of periodic-group-delay PGD dispersion compensators, and the judicious addition of some polarization-mode-dispersion (PMD) in the transmission link. It is shown that if nonlinear polarization scattering can be well mitigated, a polarization multiplexed optical coherent transmission system with dispersion management could perform better than that without it..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 844 (2010)
Analysis of smooth phase modulation formats compared with conventional QPSK and BPSK using coherent detection
Bo Huang, Nan Chi, Yufeng Shao, Junwen Zhang... and Wen Liu|Show fewer author(s)
Novel optical offset quadrature phase shift keying (OQPSK) and improved minimum-shift keying (MSK) modulation schemes to smooth optical phase hopping for high speed fiber optics transmission are proposed. Simulations have been done among the MSK, OQPSK, quadrature phase shift keying (QPSK), and binary phase-shift keyinNovel optical offset quadrature phase shift keying (OQPSK) and improved minimum-shift keying (MSK) modulation schemes to smooth optical phase hopping for high speed fiber optics transmission are proposed. Simulations have been done among the MSK, OQPSK, quadrature phase shift keying (QPSK), and binary phase-shift keying (BPSK) modulation formats at 40 Gb/s over 100-km transmission link using coherent detection. Simulation results present good performances to elevate chromatic dispersion tolerance and reduce the influence of nonlinear effects by adopting the smooth phase modulation formats. Inter-symbol interference decreases for the fast side-lobe property and tight spectrum as a result of avoding the π phase shift and reducing envelop fluctuation..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 856 (2010)
Simultaneous multichannel NRZ-to-RZ format conversion of 4-ASK signal based on phase-intensity hybrid modulation and dispersion compensation fiber
Wenke Yu, Caiyun Lou, Xiaofan Zhao, and Dan Lu
We propose and investigate a novel technique to realize non-return-to-zero (NRZ) to return-to-zero (RZ) format conversion of a multichannel 4-ary amplitude shift keying (4-ASK) signal. The proposed format converter composed of two modulators and a dispersion compensating fiber (DCF) is theoretically investigated using We propose and investigate a novel technique to realize non-return-to-zero (NRZ) to return-to-zero (RZ) format conversion of a multichannel 4-ary amplitude shift keying (4-ASK) signal. The proposed format converter composed of two modulators and a dispersion compensating fiber (DCF) is theoretically investigated using numerical simulation as basis. Research shows that a 4-channel 20-Gb/s NRZ-4-ASK signal can be converted to a RZ-4-ASK signal simultaneously without wavelength shifting and signal quality degradation, with the converted signal multiplexed to 40 Gb/s..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 859 (2010)
Digital signal processing for coherent multi-level modulation formats (Invited Paper)
Xiang Zhou
This paper presents a review on the recent progress of digital signal processing (DSP) in the high-speed optical transmission system using single-carrier based multi-level modulation formats. The principle of several digital phase and polarization tracking algorithms recently proposed and demonstrated for future spectrThis paper presents a review on the recent progress of digital signal processing (DSP) in the high-speed optical transmission system using single-carrier based multi-level modulation formats. The principle of several digital phase and polarization tracking algorithms recently proposed and demonstrated for future spectrally-efficient optical transmission system are discussed in detail. A novel DSP-based interference mitigation algorithm for the single-ended coherent receiver has been included. Recent technology advance on transmitter-side DSP such as digital pulse-shaping, pre-equalization and digital nonlinear compensation has also been discussed..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 863 (2010)
Phase pre-emphasis technique in real-time AOS-OFDM system
Hongwei Chen, Chao Tang, Feifei Yin, Minghua Chen, and Shizhong Xie
A phase pre-emphasis technique used in an all-optical sampling orthogonal frequency division multiplexing (AOS-OFDM) system is proposed and demonstrated. With the application of this technique, 50-Gb/s AOS-OFDM data are successfully transmitted over 20-km uncompensated single-mode fiber (SMF) with real-time direct-deteA phase pre-emphasis technique used in an all-optical sampling orthogonal frequency division multiplexing (AOS-OFDM) system is proposed and demonstrated. With the application of this technique, 50-Gb/s AOS-OFDM data are successfully transmitted over 20-km uncompensated single-mode fiber (SMF) with real-time direct-detection. The constructive interference effect between symbols is decreased with this technique..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 871 (2010)
Phase pre-emphasis for PAPR reduction in optical OFDM systems based on OIDFT or time lens
Jing Shao, Wei Li, and Xiaojun Liang
Phase pre-emphasis is theoretically studied and introduced to reduce peak-to-average power ratio (PAPR) in optical orthogonal frequency division multiplexing (OFDM) systems. In intensity modulated (IM) systems, simulations show noticeable PAPR reductions: 4.14 dB (N = 16) and 15.48 dB (N = 512) in time lens-based OFDM,Phase pre-emphasis is theoretically studied and introduced to reduce peak-to-average power ratio (PAPR) in optical orthogonal frequency division multiplexing (OFDM) systems. In intensity modulated (IM) systems, simulations show noticeable PAPR reductions: 4.14 dB (N = 16) and 15.48 dB (N = 512) in time lens-based OFDM, N is the number of subcarriers. An equation is developed to calculate phase values and is proved to be effective. Optical implementing methods are proposed and analyzed. In a time lens-based OFDM system, phase pre-emphasis reduces fiber nonlinearity and results in a 5.2-dB increase of launch power at the bit error rate (BER) of 10?6. Simulations also show similar PAPR reduction and fiber nonlinearity mitigation in optical inverse discrete Fourier transformer (OIDFT) based OFDM systems..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 875 (2010)
Non-feedback precoder for optical DQPSK modulation
Lumin Zhang, Yi Dong, Zhaohui Li, Hao He, and Weisheng Hu
A novel non-feedback precoder circuit for high-speed parallel optical differential quadrature phase shift keying (DQPSK) modulation is proposed. The alternative control signal is introduced in replacement of the conventional feedback one, which eliminates the speed limitation due to the electronic propagation delay. ThA novel non-feedback precoder circuit for high-speed parallel optical differential quadrature phase shift keying (DQPSK) modulation is proposed. The alternative control signal is introduced in replacement of the conventional feedback one, which eliminates the speed limitation due to the electronic propagation delay. The proposed precoder consists of four differential encoders, an exclusive OR gate, a cross switch, and delay lines. It is demonstrated by a true pseudo random bit sequence (PRBS) transmission at 20 Gb/s..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 881 (2010)
Construction of optimal 2D variable-weight optical orthogonal codes for high-speed OCDMA networks
Xiyang Li, Pingzhi Fan, and Xianfu Lei
A new construction method of two-dimensional (2D) variable-weight optical orthogonal codes (VWOOCs) is proposed for high-speed optical code-division multiple-access (OCDMA) networks supporting multiple qualities of services (QoS). The proposed codes have at most one-pulse per wavelength (AM-OPPW) property. An upper bouA new construction method of two-dimensional (2D) variable-weight optical orthogonal codes (VWOOCs) is proposed for high-speed optical code-division multiple-access (OCDMA) networks supporting multiple qualities of services (QoS). The proposed codes have at most one-pulse per wavelength (AM-OPPW) property. An upper bound of the codeword cardinality of the 2D VWOOCs with AM-OPPW property is derived. It is then shown that the constructed codes have ideal correlation properties and optimal cardinality. Moreover, the code length and the bit-error-rate (BER) performance of the proposed codes are compared with those of the codes proposed previously..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 884 (2010)
Blind frequency offset estimation based on cyclic prefix and virtual subcarriers in CO-OFDM system
Yaojun Qiao, Zhansheng Wang, and Yuefeng Ji
A new blind frequency offset estimation method based on cyclic prefix and virtual subcarriers in coherent optical orthogonal frequency division multiplexing (CO-OFDM) system is presented. It is able to estimate the fractional part and integral part of frequency offset at the same time. Its estimation range is about [?3A new blind frequency offset estimation method based on cyclic prefix and virtual subcarriers in coherent optical orthogonal frequency division multiplexing (CO-OFDM) system is presented. It is able to estimate the fractional part and integral part of frequency offset at the same time. Its estimation range is about [?3.5 GHz, 3.5 GHz]. The influence of the integral frequency offset is comprehensively analyzed in COOFDM system. Its performances in the additive white Gaussian noise (AWGN) channel and the dispersive channel are investigated, respectively. Simulation results indicate that even in the dispersive channel, when the optical signal-to-noise ratio (OSNR) is low, it can still work very well..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 888 (2010)
A novel OFDM-CPM modulation scheme and its application in WDM-PON
Yufeng Shao, Junwen Zhang, Wuliang Fang, Shumin Zou... and Siyuan Yu|Show fewer author(s)
A novel scheme to generate, transmit, and receive an optical orthogonal frequency division multiplexing (OFDM) continuous phase modulation (CPM) signal, which is combining minimum shift keying (MSK) coding with OFDM optical modulation, for downlink application in a 4×2.5-Gb/s wavelength division multiplexing (WDM)A novel scheme to generate, transmit, and receive an optical orthogonal frequency division multiplexing (OFDM) continuous phase modulation (CPM) signal, which is combining minimum shift keying (MSK) coding with OFDM optical modulation, for downlink application in a 4×2.5-Gb/s wavelength division multiplexing (WDM) passive optical access network, is proposed and experimentally validated. We also realize wavelength remodulation for carrying upstream on-off keying (OOK) data to reduce the cost budget at the optical network unit. The experimental results show that the power penalties for the downlink and the uplink data after transmission over 25-km SMF-28 fiber are 0.1 dB and smaller than 0.4 dB, respectively..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 894 (2010)
RSOA-based distributed access long reach hybrid WDM-TDM PON with OADMs
Yinbo Qian, Minming Zhang, Deming Liu, Lei Deng, and Kang Yang
A distributed access scheme using optical add/drop multiplexers (OADMs) for long reach hybrid wavelength division multiplexing and time division multiplexing passive optical networks (WDM-TDM PONs) is proposed and demonstrated. Colorless operations are implemented by using commercially available reflective semiconductoA distributed access scheme using optical add/drop multiplexers (OADMs) for long reach hybrid wavelength division multiplexing and time division multiplexing passive optical networks (WDM-TDM PONs) is proposed and demonstrated. Colorless operations are implemented by using commercially available reflective semiconductor optical amplifiers (RSOAs) at both the center office (CO) and the customer side. Four 1.25-Gb/s channels are successfully transmitted over 80-km single-mode fiber with four OADMs. The dynamic input power range of the RSOA is also investigated. Compared with traditional access schemes, the proposed scheme could cover the area along the feed fiber with no blind zone. The experimental results show that it could be an ideal solution for the next generation access networks..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 899 (2010)
Photonic ultra-wideband monocycle pulses generation using semiconductor optical amplifier and electro-absorber in parallel
Bingbing Wu, Jian Wu, Kun Xu, Xiaobin Hong... and Jintong Lin|Show fewer author(s)
A scheme for photonic generation of ultra-wideband (UWB) pulses using a semiconductor optical amplifier (SOA) and an electro-absorber (EA) in parallel is proposed and numerically demonstrated. By adjusting the time delay between two pump signals incident into the SOA and the EA, we can obtain monocycle pulses with reveA scheme for photonic generation of ultra-wideband (UWB) pulses using a semiconductor optical amplifier (SOA) and an electro-absorber (EA) in parallel is proposed and numerically demonstrated. By adjusting the time delay between two pump signals incident into the SOA and the EA, we can obtain monocycle pulses with reversed polarities and different bandwidths. The proposed method is flexible in pulse shaping and easy in practical optimization..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 902 (2010)
Optical homodyne receiver utilizing image rejection in FSK/ASK re-modulation WDM-PON
Yuan Fang, Xiao Liu, Xi Zheng, Chunning Hou... and Nan Chi|Show fewer author(s)
Optical frequency shift keying (FSK) homodyne detection utilizing image rejection in FSK/amplitude shift keying (ASK) re-modulation wavelength-division-multiplexed passive optical network (WDM-PON) is proposed and demonstrated. Image rejection is adopted to achieve better performance. We show the result in back-to-backOptical frequency shift keying (FSK) homodyne detection utilizing image rejection in FSK/amplitude shift keying (ASK) re-modulation wavelength-division-multiplexed passive optical network (WDM-PON) is proposed and demonstrated. Image rejection is adopted to achieve better performance. We show the result in back-to-back and 40-km distance respectively and apparent improvement is obtained in the latter situation by using image rejection. Several factors which affect the image rejection receiver are analyzed in order to find out the optimum parameters. Result shows that the presented scheme is suitable for super long reach access network, especially for future metro access network..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 906 (2010)
Integrated nano-structured silicon waveguides and devices for high-speed optical communications (Invited Paper)
Alan E. Willner, Lin Zhang, Yang Yue, and Xiaoxia Wu
With progress in fabrication technology, integrated photonics plays an increasingly important role in highspeed optical communications, from monolithic transmitters and receivers for advanced optical modulation formats to on-chip subsystems for optical signal processing. We review our recent work on the highly tailorabWith progress in fabrication technology, integrated photonics plays an increasingly important role in highspeed optical communications, from monolithic transmitters and receivers for advanced optical modulation formats to on-chip subsystems for optical signal processing. We review our recent work on the highly tailorable physical properties of silicon waveguides for communication and signal processing applications, using slot structures. Controllable chromatic dispersion, nonlinearity, and polarization properties of the waveguides are presented, and the enabled wideband wavelength conversion, optical tunable delay, and signal processing of polarization-multiplexing data channels are discussed..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 909 (2010)
All-optical functions based on semiconductor ring lasers (Invited Paper)
Siyuan Yu
Semiconductor ring laser (SRL) has been shown to possess robust bistability between its two possible directions, i.e., clockwise (cw) and counter-clockwise (ccw) lasing, routinely demonstrating directional extinction ratio (DER) of > 25 dB. In this paper, experimental schemes and results using the SRL as a universalSemiconductor ring laser (SRL) has been shown to possess robust bistability between its two possible directions, i.e., clockwise (cw) and counter-clockwise (ccw) lasing, routinely demonstrating directional extinction ratio (DER) of > 25 dB. In this paper, experimental schemes and results using the SRL as a universal photonic digital element to form all-optical logic, memory, and signal processing circuits are summarized. It is demonstrated that the SRL can be used for both combinatorial and sequential logic functions, and as all-optical regeneration devices. Furthermore, it is shown that a SRL logic circuit can be all-optically reconfigured to perform different all-optical logic functions..
Chinese Optics Letters
- Publication Date: Jul. 07, 2021
- Vol. 8, Issue 9, 918 (2010)
Research Articles
Editorial for Focus Issue on Enabling Science and Technology for High-Speed Optical Communications
Tingye Li, Zisen Zhao, and Jianjun Yu
Chinese Optics Letters
- Publication Date: Jul. 08, 2021
- Vol. 8, Issue 9, 815 (2010)
Novel orthogonal modulation format DRZ-FSK/DPSK for high-speed long-haul optical communication
Junwen Zhang, Yufeng Shao, Wuliang Fang, Bo Huang... and Nan Chi|Show fewer author(s)
We propose a novel advanced orthogonal modulation format dark return-to-zero frequency shift keying/differential phase shift keying (DRZ-FSK/DPSK) and its realization scheme. The DRZ-FSK/DPSK is generated by the combination of a 40-Gb/s return-to-zero (RZ) signal and a DRZ signal which is converted from the RZ using a We propose a novel advanced orthogonal modulation format dark return-to-zero frequency shift keying/differential phase shift keying (DRZ-FSK/DPSK) and its realization scheme. The DRZ-FSK/DPSK is generated by the combination of a 40-Gb/s return-to-zero (RZ) signal and a DRZ signal which is converted from the RZ using a semiconductor optical amplifier (SOA) based on nonlinear cross polarization rotation (XPR) and then re-modulated by high-bit-rate DPSK at 40 Gb/s. The feasibility of the scheme is experimentally demonstrated. Bit error rate (BER) results of the total 80-Gb/s DRZ-FSK/DPSK orthogonal modulation signal with a subsequent 100-km single-mode fiber (SMF) transmission link show its potential for future high-speed long-haul optical communication..
Chinese Optics Letters
- Publication Date: Jul. 08, 2021
- Vol. 8, Issue 9, 852 (2010)