In a free-space optical communication system employing fiber-optic components, the phasefront distortions induced by atmospheric turbulence limit the efficiency with which the laser beam is coupled into a single-mode fiber. We analyze different link scenarios including a geostationary (GEO) satellite, a high-altitude platform (HAP), and an optical ground station (OGS). Singlemode coupled optica...

We have successfully demonstrated a long-haul transmission of 32 × 10 Gbit/s and 64 × 10 Gbit/s over singlemode fiber of 650 km and 530 km respectively by using RAMANEDFA hybrid optical amplifier as inline and preamplifier amplifiers. The measured Q-factors and BER of the 32 and 64 channels after 650 and 530 km respectively (16.99–17 dB) and (10 -13 ) were higher than the standard acceptable va...

Spatial self-imaging, consisting of the periodic replication optical transverse beam profile along propagation direction, can be achieved in guided wave systems when all excited modes interfere phase. We exploited material defects photoluminescence for directly visualizing self-imaging a few-mode, nominal singlemode SMF-28 fiber. Visible luminescence was by intense femtosecond infrared pulses v...

In this paper, a simple singlemode-multimode-singlemode (SMS) optical fiber sensor is proposed and investigated for measuring the air pressure of circular thin plate. Theoretical analysis experimental demonstration are presents in paper. The changes strain bending radius SMS directly attached to plate, hence leads shifts intensity variation transmission spectrum. relationship between spectrum h...

This paper presents a theoretical and computational study on the analysis of parameters for distributed temperature sensing in optical fibers, based on spontaneous Raman scattering effect. The parameters studied were the optical power level, the range of frequency modulation and the length of the sensor element, as well as the application of optical frequency domain reflectometry (OFDR). Two di...

A singlemode-multimode-singlemode (SMS) fiber structure consists of a short section multimode fusion- spliced between two SMS fibers. The mechanism underpinning the operation an is interference and associated self-imaging. structures can be used in variety optical systems but are most commonly as sensors for parameters, ranging from macro-world measurands such temperature, strain, vibration, fl...

There has been growing interest in coherent optical orthogonal frequencydivision multiplexing (CO-OFDM). We aim to present the case that the time for CO-OFDM has come, in terms of the demand from today’s ever-advancing optical networks and the availability of its underlying technologies. We first lay out the signal processing aspect for CO-OFDM and then show a 2 2 multiple-input–multiple-output...

An optical fiber Fabry-Perot sensor to monitor the solid-liquid and liquid-solid phase changes in n-octadecane is investigated. The probe fabricated by splicing a short section of hollow core between two single-mode fibers. Light from broadband source launched into experiences multiple reflections as it travels towards cleaved end immersed material sample then back detector, creating an output ...