SIGNAL DISTRIBUTOR

PROBLEM TO BE SOLVED: To provide a signal distributor capable of taking out only the desired signal at a predetermined level by preventing sneaking signal from other systems in distributing the signal. SOLUTION: A directional coupler 29 branches an output signal of a digital head end 13 into a main system 30 and a sub-system 40. In the main system 30, an amplifier 31 amplifies the input signal level for compensation, and a level adjuster 32 adjusts the level of the input signal. A synthesizer 17 synthesizes the signal amplified and level-adjusted in the main system 30 with another re-transmission signal, and a distributor 19 distributes the synthesized signal to E/O converters 201-20n, and converts the distributed signals into optical signals and outputs them from optical fibers 211-21n. In the sub-system 40, a band limit filter 41 applies band limit to the signal branched by the directional coupler 29 and extracts only terrestrial digital broadcast, the amplifier 42 amplifies the signal and compensates the level, a level adjustor 43 adjusts it to a predetermined level, an E/O converter 20A converts the signal into an optical signal, and the optical signal is transmitted from an optical fiber 21A to a re-transmission device. COPYRIGHT: (C)2008,JPO&INPIT