At the 11th National Optics, Electro-Optics and Photonics Workshop (Photonics ’09) held on October 16th, 2009 in Ankara, Dr. Feza BÜYÜKŞAHİN ÖNCEL from the Defence Electronics and Safety Expertise Group of STM’s Systems Department made a presentation on “Modulation Formats for 25x40Gb/s Wavelength Division Multiplexing-WDM Systems”.

In the presentation, important modulation formats used in WDM systems that increase optical bandwidth by using more than one wave lengths and by combining more than one optical signals on a single fibre were explained. The presentation also included a comparison made by studying Non Return to Zero-NRZ, Return to Zero-RZ and  Carrier Suppressed Return to Zero-Differential Phase Shift Keying, which are the modulation formats used to reduce the linear and non-linear effects of fibre that cause performance reductions in  WDM systems.

In the study, Dr. ÖNCEL designed a 25- channel 40 Gb/s WDM system and conducted a simulation using the VPItransmissionMakerTM WDM software for identified modulation formats, and then conducted a system performance analysis eye diagram and bit error rate (BER) analysis for different fibre lengths.

Moreover, at the Photonics Workshop, an annual scientific meeting series focusing on optics, electro-optics and photonics, industrial and academic research and development groups come together to present and discuss works on photo sensors, electro optical materials and devices, lasers, non-linear optic devices, integrated optics, optic fibres, modelling and simulation methods, measurement and evaluation techniques, quantum optics and nano-photonic devices and systems.