We proposed an optical 4-ary frequency shift keying （FSK） modulation scheme applying dual-parallel Mach-Zehnder （MZ） modulator. The 4-ary FSK based on the single-side-band modulation scheme can greatly lower the t...We proposed an optical 4-ary frequency shift keying （FSK） modulation scheme applying dual-parallel Mach-Zehnder （MZ） modulator. The 4-ary FSK based on the single-side-band modulation scheme can greatly lower the transmission speed in each sub-carriers and increase the transmission performance, comparing with the 2-FSK signal. The transmission performance of the 4-ary FSK was demonstrated after a 50 km single mode fiber. The results showed that the 4-ary FSK can realize error-free transmission. Moreover, we analyzed the influence of factors （such as disperse compensation and demodulation bandwidth） on the transmission performance in this paper. The analysis of the influenced factors can provide a theoretical basic for experiment.展开更多
A new in-line Mach-Zehnder interferometer （MZI） sensor consisting of a stub of multi-mode fiber and an up-taper was proposed and demonstrated. Temperature measurement can be carried out by detecting wavelength shift...A new in-line Mach-Zehnder interferometer （MZI） sensor consisting of a stub of multi-mode fiber and an up-taper was proposed and demonstrated. Temperature measurement can be carried out by detecting wavelength shift. Dependency of sensitivity on interferometer length and dip wavelength was discussed. Experimental results showed a maximum temperature sensitivity of 113.6pm/℃ can be achieved, which is superior to most fiber temperature sensors based on in-line MZIs within the range from 20℃ to 80℃, also a good mechanical strength can be obtained. The proposed sensor is a good candidate for temperature measurement, due to the advantages of simple structure, easy fabrication, cost- effective and high sensitivity.展开更多
基金This work was supported by the National Natural Science Foundation of China （Grant Nos. 61471179 and 61301226）, and the High Technology Research and Development Program of China （No. 2015AA016904）.
文摘We proposed an optical 4-ary frequency shift keying （FSK） modulation scheme applying dual-parallel Mach-Zehnder （MZ） modulator. The 4-ary FSK based on the single-side-band modulation scheme can greatly lower the transmission speed in each sub-carriers and increase the transmission performance, comparing with the 2-FSK signal. The transmission performance of the 4-ary FSK was demonstrated after a 50 km single mode fiber. The results showed that the 4-ary FSK can realize error-free transmission. Moreover, we analyzed the influence of factors （such as disperse compensation and demodulation bandwidth） on the transmission performance in this paper. The analysis of the influenced factors can provide a theoretical basic for experiment.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China （Nos. 61275083 and 61290315） and the Fundamental Research Funds for the Central Universities （HUST： No. 2014CG002）.
文摘A new in-line Mach-Zehnder interferometer （MZI） sensor consisting of a stub of multi-mode fiber and an up-taper was proposed and demonstrated. Temperature measurement can be carried out by detecting wavelength shift. Dependency of sensitivity on interferometer length and dip wavelength was discussed. Experimental results showed a maximum temperature sensitivity of 113.6pm/℃ can be achieved, which is superior to most fiber temperature sensors based on in-line MZIs within the range from 20℃ to 80℃, also a good mechanical strength can be obtained. The proposed sensor is a good candidate for temperature measurement, due to the advantages of simple structure, easy fabrication, cost- effective and high sensitivity.
