in this paper, a new design of optical channel drop filter based on two- dimensional photonic crystal ring resonators with triangular lattice is proposed. the rods of this structure is silicon with the refractive index nsi=3.46 and the surrounding environment is air with the refractive index of nair=1.the widest photonic band gap obtains for the filling ratio of r/a = 0.2. the filter’s transmis...

We investigate the medium effect of a parity-time (PT)-symmetric bilayer on the quantum optical properties of an incident squeezed light at zero temperature (T=0 K). To do so, we use the canonical quantization approach and describe the amplification and dissipation properties of the constituent layers of the bilayer structure by Lorentz model to analyze the quadrature squeezing of the outgoing ...

Calibration of Optical Time Domain Reflectometer (OTDR) has a crucial role for the accurate determination of fault locations and the accurate calculation of loss budget of long-haul optical fibre links during installation and repair. A comparison has been made between the Egyptian National Institute for Standards (NIS-Egypt) and the National Metrology institute of South Africa (NMISA-South Afri...

This article deals with the possibility of employing phase sensitive OTDR (Optical Time Domain Reflectometry) into fibers with active data transmission DWDM (Dense Wavelength Division Multiplex). Due to the low backscattered signal of phase sensitive OTDR is required to generate pulses with a high intensity and short time duration. These high power pulses can cause degradation of the data trans...

A novel method for characterization of optical fiber resonators by an optical time-domain reflectometry (OTDR) technique is reported. This easy-to-use technique yields accurate results for cavity lengths ranging from a few meters to several kilometers. A simple relationship is established between the round-trip cavity loss and the position where the OTDR signal is maximum. The value obtained fo...

In this paper, a photonic crystal structure for comparing two bits has beenproposed. This structure includes four resonant rings and some nonlinear rods. Thenonlinear rods used inside the resonant rings were made of a doped glass whose linearand nonlinear refractive indices are 1.4 and 10-14 m2/W, respectively. Using Kerr effect,optical waves are guided toward the correc...

A new design approach for low-cost multiprobe reflectometers is presented. While traditional circuits adopt equally spaced probes, the solution presented here provides a method to greatly enhance the bandwidth of the measuring system by a proper choice of each probe position. As an example, a five-probe (1–16) GHz reflectometer was designed and the measurement results compared to those obtained...

In previous papers it has been shown how it is possible to sense fragmentary motion and local edge orientation to a high accuracy, directly from illuminance gradient data present in pairs of frames from a time sequence. It has also been suggested how such data may be used to generate optic flow maps. The present paper looks at the practicability of generating such optic flow maps and at the pos...

Abstract—The practical efficient approach is suggested for estimation of the seismoacoustic sources energy in C-OTDR monitoring systems. This approach is represents the sequential plan for confidence estimation both the seismoacoustic sources energy, as well the absorption coefficient of the soil. The sequential plan delivers the non-asymptotic guaranteed accuracy of obtained estimates in the f...