Patent ID: 7127176

Claim:
An optical transmission system for transmitting a radio signal over an optical fiber link for a down link, the optical transmission system comprising: a control station; and a plurality of base stations connected to one another by an optical fiber, wherein said control station comprises: a radio signal transmitter for transmitting a down electric signal; and an electrical-to-optical converter for converting the down electric signal to a down optical signal, and outputting the down optical signal to the optical fiber, wherein at least one of said base stations comprises: an amplifier-converter for converting a part of the down optical signal to the down electric signal; a radio signal amplifier for amplifying the down electric signal; and a down link antenna for transmitting the amplified down electric signal, and wherein said amplifier-converter comprises: a semiconductor optical amplifier for amplifying the down optical signal; and an electro-absorption modulator for permeating a remainder of the amplified down optical signal to transmit the remainder of the down optical signal to another base station, and detecting the part of the down optical signal to convert the part of the down optical signal to the down electric signal.