Optical back propagation

In this paper, we investigate the nonlinear and dispersion compensation efficiency in OFDM-WDM system using an advanced optical back propagation (OBP) approach based on split-step Fourier method.

7p viaespa2711 31-07-2021 28 5   Download

In this study, we propose an optical back propagation (OBP) approach for compensation of the nonlinear and dispersion distortions in direct-detection optical OFDM system. The proposed OBP using split-step Fourier method is implemented at transmitter that is suitable for high-rate OFDM-based LR-PONs applications.

10p tamynhan6 14-09-2020 12 1   Download

A novel video smoke detection method using both color and motion features is presented. The result of optical flow is assumed to be an approximation of motion field. Background estimation and color-based decision rule are used to determine candidate smoke regions. The Lucas Kanade optical flow algorithm is proposed to calculate the optical flow of candidate regions. And the motion features are calculated from the optical flow results and use to differentiate smoke from some other moving objects.

13p thaianh_k44 19-09-2012 73 10   Download

Different terms are employed in the literature to specify this method on investigations: dualbeam coherent interferometry or laser Doppler interferometry, optical coherence tomography (OCT) or optical coherence reflectometry. OCT is analogous to ultrasonic imaging, which measures the intensity of reflected infrared light rather than reflected sound waves from the sample. Time gating is employed so that the time for the light to be reflected back (or echo delay time) is used to assess the intensity of back-reflection as a function of depth.

298p ti_du_hoang 15-08-2012 71 4   Download