We proposed a new method to suppress the optical beat interference (OBI) in wavelength-division-multiplexing/subcarrier-multiple-access network. The proposed scheme uses the modulated optical pulse train that has broad bandwidth in frequency domain. Since the OBI noise is inversely proportional to the optical bandwidth of beating optical signals, the generated OBI noise by beating of optical pulse train signals from several optical network units (ONUs) spreads over wide frequency range. In addition, the chance of optical beating is low because optical pulse trains from different ONU have different pulse timing. We have demonstrated the proposed idea experimentally. In beating experiment, the carrier-to-noise ratio was obtained over 30 dBc regardless of optical beating. In addition, 6-Ms/s 16 quadrature amplitude modulator data at 0.7 GHz was successfully transmitted up to 20 km with an average error-vector-magnitude of 4.5% in presence of optical beating.
Bibliographical noteFunding Information:
Manuscript received February 15, 2005; revised May 22, 2005. This work was supported by Korean Ministry of Information and Communication. The authors are with the Department of Electrical and Electronic Engineering, Yonsei University, Seoul 120-749, Korea (e-mail: email@example.com; firstname.lastname@example.org; email@example.com). Digital Object Identifier 10.1109/LPT.2005.856354
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Electrical and Electronic Engineering