Multi-channel HDTV optical routing system utilizing dense wavelength division multiplexing technology

This paper presents three types of new optical routing systems for high-definition television (HDTV) broadcasting and describes their core technologies. They are the first systems utilizing dense wavelength division multiplexing (DWDM) technology for completely optical routing of uncompressed HDTV signals. We have developed new optical filters applicable to these systems, and performed detailed studies of the transmission performance of DWDM signals. We propose an optical waveguide filter with narrower bandwidth for future devices. This filter should also have a higher tuning speed. The systems described in this paper have been introduced in our broadcasting station, and to date their operating performance has been adequate.