Search results for "Fourier optics and signal processing"
showing 2 items of 2 documents
Fabrication of long period fiber gratings of subnanometric bandwidth.
2017
This paper reports on the fabrication of long period fiber gratings having subnanometric bandwidth in the 1500 nm spectral region. Large gratings have been photo-inscribed in a high NA fiber, the grating pitch and the order of the HE cladding mode are optimized to produce gratings with a large number of periods and preventing the coupling to TE, TM or EH modes. Resonances with a FWHM of 0.83 nm and 0.68 nm have been achieved for gratings 15 and 20 cm long respectively, the free spectral range between transmission notches is 125 nm. The polarization effects and the sensitivity of the gratings to temperature and to strain variations are presented as well. © 2015 Optical Society of America Thi…
All-fiber incoherent frequency-to-time mapping method for microwave signal generation with baseband transmission and multicasting support
2008
We present a proof-of-principle experiment for achieving simultaneous distribution of baseband radio-frequency data and up-conversion with broadcasting support over a passive optical network. The technique is based on an incoherent frequency-to-time mapping method for pulse shaping. Specifically, we synthesize the spectral density function of sliced ASE noise from an EDFA with a periodic Mach-Zehnder fiber interferometer optical filter. By using external intensity modulation combined with propagation in an optical fiber, after photodetection, the resultant averaged temporal pulse profile resembles the shape of the incoherent source. The photodetected signal contains both the baseband data a…