We propose a neural network equalization delta-sigma modulation(DSM)technique.After performing DSM on the multiorder quadrature amplitude modulation(QAM)orthogonal frequency division multiplexing(OFDM)signal at the tr...We propose a neural network equalization delta-sigma modulation(DSM)technique.After performing DSM on the multiorder quadrature amplitude modulation(QAM)orthogonal frequency division multiplexing(OFDM)signal at the transmitting end,neural network equalizer technology is used in the digital signal processing at receiving end.Applying this technology to a 4.6 km W-band millimeter wave system,it is possible to achieve a 1 Gbaud 8192-QAM OFDM signal transmission.The data rate reached 23.4 Gbit/s with the bit error rate at 3.8×10^(-2),lower than soft-decision forward-error correction threshold(4×10^(-2)).展开更多
This Letter proposes a high-security modulation scheme for optical transmission systems.By using multi-constellation shaping and asymmetric encryption,the information security can be enhanced and quantum computer crac...This Letter proposes a high-security modulation scheme for optical transmission systems.By using multi-constellation shaping and asymmetric encryption,the information security can be enhanced and quantum computer cracking can be effectively resisted.Three-dimensional(3D)carrier-less amplitude phase modulation is utilized to superposition and transmit 3D signals.Experimental verification is conducted using a seven-core weakly coupled fiber platform.The results demonstrate that the proposed scheme can effectively protect the system from any illegal attacker.展开更多
根据级联半导体光放大器（SOA）的偏振主态对准（PSP）与邦加球相关性之间的关系,研究了多级SOA级联式系统的偏振主态对准方法。提出了基于非线性偏振旋转效应（NPR）的多级SOA级联式全光开关结构。实际搭建出两级SOA级联式全光开关实...根据级联半导体光放大器（SOA）的偏振主态对准（PSP）与邦加球相关性之间的关系,研究了多级SOA级联式系统的偏振主态对准方法。提出了基于非线性偏振旋转效应（NPR）的多级SOA级联式全光开关结构。实际搭建出两级SOA级联式全光开关实验系统,并以幅值为6 m W的方波控制光对50μW信号光实现了全光开关操作,开关速度达到200 ps,优于传统的电光开关,并存在较大的提升空间。工作波段位于1510-1570 nm,插损为3.62 d B,功耗为12 m W。开关速度快、插损小、功耗低并与光纤通信系统兼容性好。该全光开关的研制成功,将有助于推动全光开关和全光网络技术的发展,以及光计算和全光信号处理等领域的技术进步。展开更多
A novel physical layer data encryption scheme using two-level constellation masking in three-dimensional(3D)carrier-less amplitude and phase modulation(CAP)passive optical network(PON)is proposed in this Letter.The ch...A novel physical layer data encryption scheme using two-level constellation masking in three-dimensional(3D)carrier-less amplitude and phase modulation(CAP)passive optical network(PON)is proposed in this Letter.The chaotic sequence generated by Chua’s circuit model realizes two-level encryption of displacement masking and constellation rotation for3 D constellations.We successfully conduct an experiment demonstrating 8.7 Gb/s 3 D-CAP-8 data transmission over25 km standard single-mode fiber.With two-level constellation masking,a key space size of 2.1×1085 is achieved to bring about high security and good encryption performance,suggesting broad application prospects in future short-range secure communications.展开更多
We present an all-optical nonreturn-to-zero/return-to-zero （NRZ/RZ） to carrier-suppressed return-to-zero （CSRZ） format conversion scheme for differential phase-shift keying （DPSK） signals. The conversion is base...We present an all-optical nonreturn-to-zero/return-to-zero （NRZ/RZ） to carrier-suppressed return-to-zero （CSRZ） format conversion scheme for differential phase-shift keying （DPSK） signals. The conversion is based on nonlinear polarization rotation of a semiconductor optical amplifier （SOA）. The 4-channel NRZ-DPSK or RZ-DPSK signals at 10 Gb/s are simultaneously converted to the corresponding CSRZ-DPSK signals, with -0.8 and 1.4 dB average power penalties, respectively. Additionally, high quality format conversion performances are shown with the optical spectra and eye diagrams.展开更多
Broad-band all-optical wavelength conversion of differential phase-shift keyed （DPSK） signal is experimentally demonstrated. This scheme is composed of a one-bit delay interferometer demodulation stage followed by a...Broad-band all-optical wavelength conversion of differential phase-shift keyed （DPSK） signal is experimentally demonstrated. This scheme is composed of a one-bit delay interferometer demodulation stage followed by a semiconductor optical amplifier （SOA） based nonlinear polarization switch. A wavelength converter for the 10 G b/s DPSK signal is presented, which has a wide wavelength range of more than 30 nm. The converted signals experience small power penalties less than 1.4 dB compared with the original signal, at a bit error rate of 10-9. Additionally, the optical spectra, the measured waveforms and the open eye diagrams of the converted signals show a high quality wavelength conversion performance.展开更多
We propose and experimentally demonstrate a novel all-optical non-return-to-zero differential-phase-shift-keying （NRZ-DPSK） to return-to-zero differentiM-phase-shift-keying （RZ-DPSK） format conversion scheme. This...We propose and experimentally demonstrate a novel all-optical non-return-to-zero differential-phase-shift-keying （NRZ-DPSK） to return-to-zero differentiM-phase-shift-keying （RZ-DPSK） format conversion scheme. This scheme is based on the terahertz optical asymmetric demultiplexer （TOAD）. A 10 Gb/s converted RZ-DPSK signal is obtained with a wide duty cycle tuning range from 16% to 66%. For all converted RZ-DPSK signals, the receiver sensitivities at BER of 10-9 are 0.4 to 1.7dB higher compared with the original NRZ-DPSK signal. The clear and open eye diagrams are presented to demonstrate the high quality format conversion performance. Moreover, the optical spectra show that this conversion is in a wavelength-preserving operation.展开更多
The internal optical loss in semiconductor optical amplifiers(SOAs)is investigated experimentally and theoretically over a wide injection current range.A new measurement method is proposed without noise figure spectra...The internal optical loss in semiconductor optical amplifiers(SOAs)is investigated experimentally and theoretically over a wide injection current range.A new measurement method is proposed without noise figure spectra.Theoretically,considering the internal loss in an SOA,a modified formula of the input-output characteristics is deduced.Based on the practically measured input-output characteristic curves,the internal loss coefficient of an SOA is measured at different injection currents.The results demonstrate that the internal loss coefficient of SOAs decreases with increasing injection current.展开更多
A novel scheme of all-optical time slot interchanger employing two cascaded re-circulating optical buffers based on nonlinear polarization rotation in semiconductor optical amplifiers is proposed.The experimental syst...A novel scheme of all-optical time slot interchanger employing two cascaded re-circulating optical buffers based on nonlinear polarization rotation in semiconductor optical amplifiers is proposed.The experimental system exhibits full interchangeable capability on three 512-bit packets at 10 Gbits/s.Theoretically,each packet length is up to 123 ns with the maximum buffer depth 30%.展开更多
基金supported by the National Natural Science Foundation of China(Nos.62225503,61835005,and 62205151)。
文摘We propose a neural network equalization delta-sigma modulation(DSM)technique.After performing DSM on the multiorder quadrature amplitude modulation(QAM)orthogonal frequency division multiplexing(OFDM)signal at the transmitting end,neural network equalizer technology is used in the digital signal processing at receiving end.Applying this technology to a 4.6 km W-band millimeter wave system,it is possible to achieve a 1 Gbaud 8192-QAM OFDM signal transmission.The data rate reached 23.4 Gbit/s with the bit error rate at 3.8×10^(-2),lower than soft-decision forward-error correction threshold(4×10^(-2)).
基金supported by the National Key Research and Development Program of China(No.2021YFB2800904)the National Natural Science Foundation of China(Nos.62225503,61835005,62205151,62171227,and 61935005)+2 种基金the Jiangsu Provincial Key Research and Development Program(Nos.BE2022079andBE2022055-2)theNaturalScience Foundation of the Jiangsu Higher Education Institutions of China(No.22KJB510031)the Startup Foundation for Introducing Talent of NUIST。
文摘This Letter proposes a high-security modulation scheme for optical transmission systems.By using multi-constellation shaping and asymmetric encryption,the information security can be enhanced and quantum computer cracking can be effectively resisted.Three-dimensional(3D)carrier-less amplitude phase modulation is utilized to superposition and transmit 3D signals.Experimental verification is conducted using a seven-core weakly coupled fiber platform.The results demonstrate that the proposed scheme can effectively protect the system from any illegal attacker.
文摘根据级联半导体光放大器（SOA）的偏振主态对准（PSP）与邦加球相关性之间的关系,研究了多级SOA级联式系统的偏振主态对准方法。提出了基于非线性偏振旋转效应（NPR）的多级SOA级联式全光开关结构。实际搭建出两级SOA级联式全光开关实验系统,并以幅值为6 m W的方波控制光对50μW信号光实现了全光开关操作,开关速度达到200 ps,优于传统的电光开关,并存在较大的提升空间。工作波段位于1510-1570 nm,插损为3.62 d B,功耗为12 m W。开关速度快、插损小、功耗低并与光纤通信系统兼容性好。该全光开关的研制成功,将有助于推动全光开关和全光网络技术的发展,以及光计算和全光信号处理等领域的技术进步。
基金the National Key Research and Development Program of China(No.2018YFB1801302)National Natural Science Foundation of China(Nos.61835005,61822507,61522501,61475024,61675004,61705107,61727817,61775098,61720106015,and 61875248)+2 种基金Beijing Young Talent(No.2016000026833ZK15)Open Fund of IPOC(BUPT)(No.IPOC2019A011)Jiangsu Talent of Innovation and Entrepreneurship,Jiangsu Team of Innovation and Entrepreneurship,and Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX200963)。
文摘A novel physical layer data encryption scheme using two-level constellation masking in three-dimensional(3D)carrier-less amplitude and phase modulation(CAP)passive optical network(PON)is proposed in this Letter.The chaotic sequence generated by Chua’s circuit model realizes two-level encryption of displacement masking and constellation rotation for3 D constellations.We successfully conduct an experiment demonstrating 8.7 Gb/s 3 D-CAP-8 data transmission over25 km standard single-mode fiber.With two-level constellation masking,a key space size of 2.1×1085 is achieved to bring about high security and good encryption performance,suggesting broad application prospects in future short-range secure communications.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61425022,61522501,61675004,61307086,61475024,61672290,61475094 and 61605013the National Basic Research Program of China under Grant Nos2015AA015501,2015AA015502,2015AA015504,2015AA016904 and 2015AA016901the Beijing Nova Program under Grant No Z141101001814048
文摘We present an all-optical nonreturn-to-zero/return-to-zero （NRZ/RZ） to carrier-suppressed return-to-zero （CSRZ） format conversion scheme for differential phase-shift keying （DPSK） signals. The conversion is based on nonlinear polarization rotation of a semiconductor optical amplifier （SOA）. The 4-channel NRZ-DPSK or RZ-DPSK signals at 10 Gb/s are simultaneously converted to the corresponding CSRZ-DPSK signals, with -0.8 and 1.4 dB average power penalties, respectively. Additionally, high quality format conversion performances are shown with the optical spectra and eye diagrams.
文摘Broad-band all-optical wavelength conversion of differential phase-shift keyed （DPSK） signal is experimentally demonstrated. This scheme is composed of a one-bit delay interferometer demodulation stage followed by a semiconductor optical amplifier （SOA） based nonlinear polarization switch. A wavelength converter for the 10 G b/s DPSK signal is presented, which has a wide wavelength range of more than 30 nm. The converted signals experience small power penalties less than 1.4 dB compared with the original signal, at a bit error rate of 10-9. Additionally, the optical spectra, the measured waveforms and the open eye diagrams of the converted signals show a high quality wavelength conversion performance.
文摘We propose and experimentally demonstrate a novel all-optical non-return-to-zero differential-phase-shift-keying （NRZ-DPSK） to return-to-zero differentiM-phase-shift-keying （RZ-DPSK） format conversion scheme. This scheme is based on the terahertz optical asymmetric demultiplexer （TOAD）. A 10 Gb/s converted RZ-DPSK signal is obtained with a wide duty cycle tuning range from 16% to 66%. For all converted RZ-DPSK signals, the receiver sensitivities at BER of 10-9 are 0.4 to 1.7dB higher compared with the original NRZ-DPSK signal. The clear and open eye diagrams are presented to demonstrate the high quality format conversion performance. Moreover, the optical spectra show that this conversion is in a wavelength-preserving operation.
基金the National Natural Science Foundation of China under Grant Nos 61275075 and 61077048the Natural Science Foundation of Beijing under Grant No 4112042.
文摘The internal optical loss in semiconductor optical amplifiers(SOAs)is investigated experimentally and theoretically over a wide injection current range.A new measurement method is proposed without noise figure spectra.Theoretically,considering the internal loss in an SOA,a modified formula of the input-output characteristics is deduced.Based on the practically measured input-output characteristic curves,the internal loss coefficient of an SOA is measured at different injection currents.The results demonstrate that the internal loss coefficient of SOAs decreases with increasing injection current.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61177082 and 60907027the Natural Science Foundation of Beijing under Grant No 4122063.
文摘A novel scheme of all-optical time slot interchanger employing two cascaded re-circulating optical buffers based on nonlinear polarization rotation in semiconductor optical amplifiers is proposed.The experimental system exhibits full interchangeable capability on three 512-bit packets at 10 Gbits/s.Theoretically,each packet length is up to 123 ns with the maximum buffer depth 30%.
