Patent ID: 7349634
Filing Date: 2008-03-25
Classification: H04B

Abstract:
1. An optical transmission system comprising: a center station; and a plurality of radio base stations connected to the center station with a plurality of optical fibers, the plurality of radio base stations covering different service areas, wherein said center station includes: wherein the electric signal inputted to each of the plurality of IF modulation portions is one or more IF signals in which one or more baseband signals are modulated by different predetermined intermediate frequencies respectively, wherein each of said plurality of IF modulation portions intensity-modulates the respective optical signal such that only an IF signal component used in a service area covered by a corresponding radio base station is transmitted, and wherein said plurality of radio base stations each includes: an antenna portion for transmitting and receiving radio signals to a subscriber terminal; and at least an optical-electrical conversion portion for converting the corresponding one of the optical signals transmitted through the plurality of optical fibers into an electric signal in a radio frequency band, and feeding the converted electric signal to said antenna portion without passing the converted electric signal through a filter.