Progress in the development of a digital optical routing system for television studio centres

A system that uses a combination of optical wavelength-division multiplexing (WDM) and electrical time-division multiplexing (TDM) to distribute signals from all sources to all destinations has been proposed; this combination has become known as the WTDM system. The present paper is a progress report describing the recent development of the WTDM system. It gives an outline of the system and shows why a standards-independent routing system is attractive to broadcasters. It then describes the RACE programme and the BBC-led project that is developing the system. Finally it gives details of the system specification, with particular emphasis on the methods of multiplexing together the different signal formats that will be needed in the television studio centre of the future