<div style="text-align:justify;"> Dual polarization quadrature phase shift keying (DP-QPSK) is currently the main modulation format for high-speed optical fiber communications, and its simulation model...<div style="text-align:justify;"> Dual polarization quadrature phase shift keying (DP-QPSK) is currently the main modulation format for high-speed optical fiber communications, and its simulation modeling has important implications for theoretical research and practical applications. Based on Optisystem 15 optical communication system simulation software, this paper builds a 100 Gbit/s rate DP-QPSK modulation format coherent optical transmission system simulation model, analyzes the working principles of the transmitting end, transmission link, and coherent receiver. The principle of signal recovery at the digital signal processing end is briefly explained. The simulation results show that the signal quality after DSP processing has been significantly improved. </div>展开更多
We propose and analyze an instantaneous frequency measurement system by using optical power monitoring technique with improved resolution.The primary component adopted in the proposal is a dual-polarization quadrature...We propose and analyze an instantaneous frequency measurement system by using optical power monitoring technique with improved resolution.The primary component adopted in the proposal is a dual-polarization quadrature phase shift keying(DP-QPSK) modulator which is used to modulate the microwave signal that has a designed time delay and phase shifting.The generated optical signal is sent to polarization beam splitter(PBS) in DP-QPSK modulator.Owing to the complementary transmission nature of polarization interference introduced by PBS,the frequency information is converted into the optical power and the relationship between the amplitude comparison function(ACF) and microwave frequency to be measured is established.Thus,the frequency of the microwave signal can be easily measured through monitoring the optical powers of the two output ports of the PBS.Furthermore,by adjusting the direct current(DC) biases of the DP-QPSK modulator instead of changing the electrical delay,the measurement range and resolution can be switched.In this paper,the basic principle of the instantaneous frequency measurement system is derived in detail,and simulation has been performed to investigate the resolution,the measurement range,and the influence of imperfection devices.The proposed scheme is wavelength-independent and its measurement range is switchable,which can avoid the laser wavelength drifting problem and thus greatly increasing the system flexibility.展开更多
文摘<div style="text-align:justify;"> Dual polarization quadrature phase shift keying (DP-QPSK) is currently the main modulation format for high-speed optical fiber communications, and its simulation modeling has important implications for theoretical research and practical applications. Based on Optisystem 15 optical communication system simulation software, this paper builds a 100 Gbit/s rate DP-QPSK modulation format coherent optical transmission system simulation model, analyzes the working principles of the transmitting end, transmission link, and coherent receiver. The principle of signal recovery at the digital signal processing end is briefly explained. The simulation results show that the signal quality after DSP processing has been significantly improved. </div>
基金Project supported by the National Natural Science Foundation of China(Grant No.61801017,U2006217,62005011,and 61620106014)Beijing Municipal Natural Science Foundation(Grant No.4212009)the Fundamental Research Funds for the Central Universities(Grant No.2020JBM010)。
文摘We propose and analyze an instantaneous frequency measurement system by using optical power monitoring technique with improved resolution.The primary component adopted in the proposal is a dual-polarization quadrature phase shift keying(DP-QPSK) modulator which is used to modulate the microwave signal that has a designed time delay and phase shifting.The generated optical signal is sent to polarization beam splitter(PBS) in DP-QPSK modulator.Owing to the complementary transmission nature of polarization interference introduced by PBS,the frequency information is converted into the optical power and the relationship between the amplitude comparison function(ACF) and microwave frequency to be measured is established.Thus,the frequency of the microwave signal can be easily measured through monitoring the optical powers of the two output ports of the PBS.Furthermore,by adjusting the direct current(DC) biases of the DP-QPSK modulator instead of changing the electrical delay,the measurement range and resolution can be switched.In this paper,the basic principle of the instantaneous frequency measurement system is derived in detail,and simulation has been performed to investigate the resolution,the measurement range,and the influence of imperfection devices.The proposed scheme is wavelength-independent and its measurement range is switchable,which can avoid the laser wavelength drifting problem and thus greatly increasing the system flexibility.