Abstract: Dense wavelength division multiplexing (DWDM) technology requires tight specification and therefore measurement of wavelength accuracy and stability of the telecommunication lasers. Thus, calibration of the used Optical Spectrum Analyzers (OSAs) that are used to measure wavelength is of a great importance. Proficiency testing must be performed on such measuring activity to insure the accuracy of the measurement results. In this paper, a new comparison scheme is introduced to test the performance of such calibrations. This comparison scheme is implemented between NIS-Egypt and NMISA-South Africa for the calibration of the wavelength scale of an OSA. Both institutes employ reference gas cell to calibrate OSA according to the standard IEC/ BS EN 62129 (2006). The result of this comparison is compiled in this paper.
Abstract: We report the design and characterization of ultra high
quality factor filter based on one-dimensional photonic-crystal Thue-
Morse sequence structure. The behavior of aperiodic array of
photonic crystal structure is numerically investigated and we show
that by changing the angle of incident wave, desired wavelengths
could be tuned and a tunable filter is realized. Also it is shown that
high quality factor filter be achieved in the telecommunication
window around 1550 nm, with a device based on Thue-Morse
structure. Simulation results show that the proposed structure has a
quality factor more than 100000 and it is suitable for DWDM
communication applications.
Abstract: ICT services are a key element of communications and important for socio-economic development. In recognition of the importance of this, the Tanzanian Government started to implement a National ICT Broadband Infrastructure Fibre Optic Backbone (NICTBB) in 2009; this development was planned to be implemented in four phases using an optical dense wavelength division multiplexing (DWDM) network technology in collaboration with the Chinese Government through the Chinese International Telecommunications Construction Corporation (CITCC) under a bilateral agreement. This paper briefly explores the NICTBB network technologies implementation, operations and Internet bandwidth costs. It also provides an in depth assessment of the delivery of ICT services such as e-services and m-services in both urban and rural areas following commissioning of the NICTBB system. Following quantitative and qualitative approaches, the study shows that there have been significant improvements in utilization efficiency, effectiveness and the reliability of the ICT service such as e-services and m-services the NICTCBB was commissioned.
Abstract: In this paper, the gain spectrum of EDFA has been broadened by implementing HTE configuration for S and C band. On using this configuration an amplification bandwidth of 76nm ranging from 1479nm to 1555nm with a peak gain of 26dB has been obtained.
Abstract: This paper presents an investigation of the power
penalties imposed by four-wave mixing (FWM) on G.652 (Single-
Mode Fiber - SMF), G.653 (Dispersion-Shifted Fiber - DSF), and
G.655 (Non-Zero Dispersion-Shifted Fiber - NZDSF) compliant
fibers, considering the DWDM grids suggested by the ITU-T
Recommendations G.692, and G.694.1, with uniform channel
spacing of 100, 50, 25, and 12.5 GHz. The mathematical/numerical
model assumes undepleted pumping, and shows very clearly the
deleterious effect of FWM on the performance of DWDM systems,
measured by the signal-to-noise ratio (SNR). The results make it
evident that non-uniform channel spacing is practically mandatory
for WDM systems based on DSF fibers.