近几年来,光纤通信向长波长迅速发展,其主要原因在于长波长光纤衰耗小、色散小,这意味着允许在较长中继间隔和较高毕特率工作,同时也意味着线路成本降低。目前,三次群长波长多模光纤系统对市话中继和长途通信具有很大吸引力。本文报导全长为21.6公里,速率为34Mb/s,波长为1.3μm的光纤通信系统实验。 In recent years, optical fiber communications to the rapid development of long wavelengths, mainly due to long-wavelength fiber attenuation of small, small dispersion, which means allowing longer relay intervals and higher bit rate work, but also means that the line costs reduce. At present, the triple-group long-wavelength multimode optical fiber system has great appeal to local relay and long-distance communication. This paper reports the experiment of optical fiber communication system with a total length of 21.6 km, a speed of 34Mb / s and a wavelength of 1.3μm.