This part of IEC 61603 specifies the characteristics and measuring methods for digital audio signal transmission systems using infrared radiation with sub-carrier of the frequency ranges 3 MHz to 6 MHz. It describes systems with different economic uses of the available bandwidth in order to obtain minimum interference and maximum compatibility.
DS/EN 61603-8-1:2004 history
2004DS/EN 61603-8-1:2004 Transmission of audio and/or video and related signals using infrared radiation - Part 8-1: Digital audio and related signals