| 摘要 |
<P>PROBLEM TO BE SOLVED: To realize a FTTH (fiber to the home) method CATV system capable of operating multiple bidirectional communication services. <P>SOLUTION: As shown in Fig. 2, an optical terminal machine 11 includes an E/O converter 100, a level control part 102, and an amplifier part 103. The spectral width of an upstream optical signal to be output from the E/O converter 100 is equal to or more than 0.5 nm. The amplifier part 103 amplifies an upstream electric signal thereby to allow a modulation degree to be equal to or more than 20%. The level control part 102 controls the level of the upstream optical signal thereby to allow the levels of the respective upstream optical signals to be substantially the same when reaching a center. Consequently, upstream communication is normally performed even with the occurrence of optical beat interference (OBI). <P>COPYRIGHT: (C)2012,JPO&INPIT |
