The interference protection ratio is a primary parameter for the broadcasting-satellite service CBSS) (television); certain values of protection ratios for television signals have already been used for planning purposes by the WARC-BS-77 and RARC SAT-83;more accurate values of protection ratio required for frequency modulated television systems, using time domain multiplex for the video components, and digital techniques for associated sound and data, are now well established;the existing Plans for the BSS in the 12 GHz band may be reconsidered in the future and that the planning will require protection ratio data for the types of wanted and interfering signals involved; the selectivity characteristics of receiving equipment for the BSS (television) are designed Ling into account these values.