We experimentally demonstrate a tunable and reconfigurable optical discrete Fourier transform (DFT) to demultiplex orthogonal-frequency-division-multiplexed subcarriers with 2/3/4 subcarriers at 20/40 GHz frequency spacing. An average power penalty of ~5 dB (~3.5) at bit error ratio of 10(-9) is achieved for 4×20 Gbit/s (4×10 Gbit/s) OFDM signal with 20 GHz frequency spacing.

Time-frequency distributions have been used extensively for nonstationary signal analysis, they describe how the frequency content of a signal is changing in time. The Wigner-Ville distribution (WVD) is the best known. The draw back of WVD is cross-term artifacts. An alternative to the WVD is Gabor transform (GT), a signal decomposition method, which displays the time-frequency energy of a sign...

The combination of gas chromatography (GC) with Fourier transform infrared spectroscopy (FTIR) has gradually become the important analytical tool for qualitative and quantitative analysis of complex mixtures. Numerous applications have been reported in previous reviews. Separation and identification of components in complex mixtures can be a daunting task. GC is the most common technique for se...

in this paper, cuo nanoparticles  have been synthesized via solid-state thermal decomposition using copper(ii) schiff base complexes as new precursors at 600ºc under air atmosphere for 3 h. surface morphology of the products were characterized by fourier transform infrared spectroscopy (ft-ir), x-ray diffraction (xrd) and scanning electron microscopy (sem).

the purpose of the current research is investigating the phenylalanine removal by using magnetic nanoparticles (fe3o4) from water samples. the effect of ph, contact time and phenylalanine concentration on phenylalanine adsorption efficiency by magnetite nanoparticles are studied in a batch system. transmission electron microscopy (tem), x-ray diffraction patterns (xrd) and fourier transform inf...