Title :
Upstream-FDMA/downstream-TDM optical fiber multiaccess network
Author :
Shiozawa, Takahiro ; Shibutani, M. ; Namiki, J.
Author_Institution :
NEC Corp., Kanagawa
Abstract :
An optical fiber subscriber network requires both bidirectional transmission and multiple-access upstream transmission. An upstream-frequency-division-multiple access (UFDMA)/downstream-time-division multiplexing (DTDM) optical fiber multiaccess network that provides such an optical fiber subscriber network is discussed. The UFDMA/DTDM network uses electronic FDMA for upstream multiple access and a electronic frequency-division multiplexing (FDM) forbidirectional transmission. A TDM signal, modulated at a different frequency than the upstream signals, is used for downstream transmission in the broadcasting mode. Wide optical spectral linewidth light sources are used in the transmitter for upstream transmission to avoid optical beat interference. The merits of the UFDMA/DTDM network are summarized. The carrier-to-noise ratio (CNR) and the dispersion power penalty are calculated to determine the channel capacity. For example, in 1.5-μm wavelength region, 800-Mb/s maximum downstream channel capacity and 1.5-Mb/s maximum upstream channel capacity are applicable for 32 network terminators with 10-km optical fiber trunks
Keywords :
broadband networks; channel capacity; digital communication systems; frequency division multiple access; frequency division multiplexing; interference (signal); optical dispersion; optical fibres; optical links; subscriber loops; time division multiplexing; 1.5 Mbit/s; 1.5 micron; 10 km; 800 Mbit/s; CNR; FDM; bidirectional transmission; carrier-to-noise ratio; channel capacity; dispersion power penalty; downstream-TDM; electronic FDMA; electronic frequency-division multiplexing; frequency-division-multiple access; multiple-access upstream transmission; optical fiber multiaccess network; optical fibre links; subscriber network; time-division multiplexing; upstream multiple access; Broadcasting; Channel capacity; Frequency division multiaccess; Frequency division multiplexing; Interference; Light sources; Optical fibers; Optical modulation; Optical transmitters; Time division multiplexing;
Journal_Title :
Lightwave Technology, Journal of
