A passive optical network(PON) monitoring system combined light pulse and frequency sweep techniques is proposed and verified in a field test. The light pulse surveys over the all whole network and the frequency swe...A passive optical network(PON) monitoring system combined light pulse and frequency sweep techniques is proposed and verified in a field test. The light pulse surveys over the all whole network and the frequency sweep are used to investigate any fault in the link. The field test is performed with 4 PONs. Each PON is monitored at 4 ports, one is the splitter port and the other three are arbitrary chosen multiple optical units(ONUs). All the tested PONs are monitored in turns once per hour. Faults at the feeder and branch fiber have been observed in this field test and have been analyzed with the monitoring system.展开更多
Modal analysis of the 1×3 highly efficient reflective triangular grating operating in the 800 nm wavelength under normal incidence for TE polarization is presented in this Letter.The rigorous coupled wave analysi...Modal analysis of the 1×3 highly efficient reflective triangular grating operating in the 800 nm wavelength under normal incidence for TE polarization is presented in this Letter.The rigorous coupled wave analysis and simulated annealing algorithm are used to design this beam splitter.The reflective grating consists of a highly reflective mirror and a transmission grating on the top.The mechanism of the reflective triangular grating is clarified by the simplified modal method.Then,gratings are fabricated by direct laser writing lithography.展开更多
文摘A passive optical network(PON) monitoring system combined light pulse and frequency sweep techniques is proposed and verified in a field test. The light pulse surveys over the all whole network and the frequency sweep are used to investigate any fault in the link. The field test is performed with 4 PONs. Each PON is monitored at 4 ports, one is the splitter port and the other three are arbitrary chosen multiple optical units(ONUs). All the tested PONs are monitored in turns once per hour. Faults at the feeder and branch fiber have been observed in this field test and have been analyzed with the monitoring system.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.61307064 and 61405214)the Ministry of Science and Technology of China(MOST)(No.2012YQ170004)
文摘Modal analysis of the 1×3 highly efficient reflective triangular grating operating in the 800 nm wavelength under normal incidence for TE polarization is presented in this Letter.The rigorous coupled wave analysis and simulated annealing algorithm are used to design this beam splitter.The reflective grating consists of a highly reflective mirror and a transmission grating on the top.The mechanism of the reflective triangular grating is clarified by the simplified modal method.Then,gratings are fabricated by direct laser writing lithography.