The adaptive polarization mode dispersion(PMD) compensation in high-speed transmission system has become more and more necessary for the link PMD causing strong signal distortions.A dynamic adaptive PMD compensator in...The adaptive polarization mode dispersion(PMD) compensation in high-speed transmission system has become more and more necessary for the link PMD causing strong signal distortions.A dynamic adaptive PMD compensator in 40 Gb/s polar-multiplex differential quadrature phase shift keying(PM-DQPSK) system is reported.Experimental results show that the PMD compensator can track the average polarization state variation at 65 rad/s without any lost of the optimum tracking.The 1st-order PMD compensation is demonstrated experimentally,and the compensator can increase the maximal tolerable PMD value by 26 ps from 17 ps to 43 ps in an optical transmission system.展开更多
An endless polarization stabilization control system is proposed in this letter. The system is independent of transmission data rate and modulation format, and it does not need high-speed circuit to track fast polariz...An endless polarization stabilization control system is proposed in this letter. The system is independent of transmission data rate and modulation format, and it does not need high-speed circuit to track fast polarization change. Adaptive inertia weight particle swarm optimization algorithm is used and the effectiveness of polarization stabilization control is experimentally verified.展开更多
In this paper,we propose and experimentally demonstrate an auto-bias control scheme for stabilizing a lithium niobate(LN)Mach-Zehnder modulator(MZM)at any operating point along the power transmission curve.It is based...In this paper,we propose and experimentally demonstrate an auto-bias control scheme for stabilizing a lithium niobate(LN)Mach-Zehnder modulator(MZM)at any operating point along the power transmission curve.It is based on that the bias drift would change the operating point and result in varying the output optical average power of the Mach-Zehnder modulator and its first and second derivatives.The ratio of the first to the second derivative of the output optical average power is used in the proposed scheme as the key parameter.The experimental results show that the output optical average power of the LN MZM hardly changes at the desired operating point,and the maximum deviation of output optical average power is less than±4%.展开更多
A novel scheme employing low-density parity-check (LDPC) codes in atmospheric optical communication system is proposed. We deploy coherent detection at the receiving side in the proposed scheme. To reduce bit error ra...A novel scheme employing low-density parity-check (LDPC) codes in atmospheric optical communication system is proposed. We deploy coherent detection at the receiving side in the proposed scheme. To reduce bit error rate (BER) and enhance the system performance, LDPC codes are exploited and coherent receiver is used to improve the receiving sensitivity. Experiments are implemented to evaluate the performance of the transmission system. The atmospheric channel attenuations are set to 20-30 dB/km. The coherent detection with LDPC codes can reduce the received power requirement by ~4 dBm at the BER of 10-9.展开更多
A new cross-tracking method is proposed to improve the convergent speed of the control algorithm in real-time polarization mode dispersion（PMD）compensation systems.The cross-tracking algorithm is compared with the p...A new cross-tracking method is proposed to improve the convergent speed of the control algorithm in real-time polarization mode dispersion（PMD）compensation systems.The cross-tracking algorithm is compared with the previously used dithering particle swarm optimization（DPSO）and gradient particle swarm optimization（GPSO）algorithms,and it is proven to offer the best performance among the three algorithms.The transmission of a 43-Gb/s differential quadrature phase-shift keying（DQPSK）signal over a 1 200-km fiber span using a compensator based on digital signal processing（DSP）is demonstrated via the cross-tracking algorithm.展开更多
基金supported by the National High Technology Research and Development Program of China (No.2009AA01Z224)the Fundamental Research Funds for the Central Universities (Nos.2009RC0401 and 2009RC0405)the China Postdoctoral Science Foundation Project (No.20100470259)
文摘The adaptive polarization mode dispersion(PMD) compensation in high-speed transmission system has become more and more necessary for the link PMD causing strong signal distortions.A dynamic adaptive PMD compensator in 40 Gb/s polar-multiplex differential quadrature phase shift keying(PM-DQPSK) system is reported.Experimental results show that the PMD compensator can track the average polarization state variation at 65 rad/s without any lost of the optimum tracking.The 1st-order PMD compensation is demonstrated experimentally,and the compensator can increase the maximal tolerable PMD value by 26 ps from 17 ps to 43 ps in an optical transmission system.
基金supported by the Fundamental Research Funds for the Central Universities(Nos.2012RC0407 and 2012RC0406)the National Major Scientific Instruments and Equipments Development Project,which belongs to the Ministry of Science and Technology of China(No.2012YQ170059)the National 863 Project of China(No.2013AA013601)
文摘An endless polarization stabilization control system is proposed in this letter. The system is independent of transmission data rate and modulation format, and it does not need high-speed circuit to track fast polarization change. Adaptive inertia weight particle swarm optimization algorithm is used and the effectiveness of polarization stabilization control is experimentally verified.
基金the Fund of Young Scholar Innovation Project(Nos.2012RC0407 and 2012RC0406)
文摘In this paper,we propose and experimentally demonstrate an auto-bias control scheme for stabilizing a lithium niobate(LN)Mach-Zehnder modulator(MZM)at any operating point along the power transmission curve.It is based on that the bias drift would change the operating point and result in varying the output optical average power of the Mach-Zehnder modulator and its first and second derivatives.The ratio of the first to the second derivative of the output optical average power is used in the proposed scheme as the key parameter.The experimental results show that the output optical average power of the LN MZM hardly changes at the desired operating point,and the maximum deviation of output optical average power is less than±4%.
基金supported by the Fundamental Research Funds for the Central Universities (No.2009RC0401)the Young Scholar Innovation Project (Nos.2011PTB-00-31, 2012RC0407 and 2012RC0406)
文摘A novel scheme employing low-density parity-check (LDPC) codes in atmospheric optical communication system is proposed. We deploy coherent detection at the receiving side in the proposed scheme. To reduce bit error rate (BER) and enhance the system performance, LDPC codes are exploited and coherent receiver is used to improve the receiving sensitivity. Experiments are implemented to evaluate the performance of the transmission system. The atmospheric channel attenuations are set to 20-30 dB/km. The coherent detection with LDPC codes can reduce the received power requirement by ~4 dBm at the BER of 10-9.
基金supported by the National "863" Program of China(No.2009AA01Z224)the Fundamental Research Funds for the Central Universities(Nos.2009RC0401 and 2009RC0405)the China Postdoctoral Science Foundation(No.20100470259)
文摘A new cross-tracking method is proposed to improve the convergent speed of the control algorithm in real-time polarization mode dispersion（PMD）compensation systems.The cross-tracking algorithm is compared with the previously used dithering particle swarm optimization（DPSO）and gradient particle swarm optimization（GPSO）algorithms,and it is proven to offer the best performance among the three algorithms.The transmission of a 43-Gb/s differential quadrature phase-shift keying（DQPSK）signal over a 1 200-km fiber span using a compensator based on digital signal processing（DSP）is demonstrated via the cross-tracking algorithm.
