Characterization of Gigabit Ethernet Over Highly Turbulent Optical Wireless Links.

Johnson, G. W. ; Cornish, J. P. ; Wilburn, J. W. ; Young, R. A. ; Ruggiero, A. J.

Technical Information Center Oak Ridge Tennessee

关键词: Ethernet;    Gigabit;    Optical communication;    WDM;    Free space optics;   

RP-ID  :  DE200515013336

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

We report on the performance characterization and issues associated with using Gigabit Ethernet (GigE) over a highly turbulent (C(sup 2)(sub n) > 10(sup-12)) 1.3 km air-optic lasercom links. Commercial GigE hardware is a cost-effective and scalable physical layer standard that can be applied to air-optic communications. We demonstrate a simple GigE hardware interface to a singlemode fiber-coupled, 1550 nm, WDM air-optic transceiver. TCPAP serves as a robust and universal foundation protocol that has some tolerance of data loss due to atmospheric fading. Challenges include establishing and maintaining a connection with acceptable throughput under poor propagation conditions. The most useful link performance diagnostic is shown to be scintillation index, where a value of 0.2 is the maximum permissible for adequate GigE throughput. Maximum GigE throughput observed was 49.7% of that obtained with a fiber jumper when scintillation index is 0.1. Shortcomings in conventional measurements such as bit error rate are apparent. Prospects for forward error correction and other link enhancements will be discussed.