| 20090204988 | ANNOUNCEMENT BROADCASTING SYSTEM, ANNOUNCEMENT BROADCASTING OPTICAL RECEIVER USED FOR THE ANNOUNCEMENT BROADCASTING SYSTEM, CABLE TELEVISION BROADCASTING SYSTEM, AND OPTICAL RECEIVER USED FOR THE CABLE TELEVISION BROADCASTING SYSTEM - In a subscriber's facility of an announcement broadcasting system utilizing an optical fiber cable TV network, an announcement broadcasting optical receiver receiving an optical transmission signal of audio information and outputting an audio information electric signal for an announcement broadcasting terminal is provided. The announcement broadcasting optical receiver includes: a photo-detection section for converting the optical transmission signal into the audio information electric signal; a photoelectric conversion section, which is connected to the photo-detection section, for converting the optical transmission signal that the photo-detection section receives into electric energy; and an RF signal potential transformation section, to which the electric energy obtained by the photoelectric conversion section is supplied, for potential-transforming the audio information electric signal output from the photo-detection section to one at an input voltage level appropriate to the announcement broadcasting terminal and outputting it. | 08-13-2009 |
