Introduction There are a large number of possible methods of modulation for the broadcasting satellite service@ the choice depending on several factors. This Report discusses different technically suitable methods for the broadcasting-satellite service in all the frequency bands allocated to this service. As regards the broadcasting-satellite service in the 12 GHz band@ it should be borne in mind that the planning at the WARC-BS-77 was carried out on the assumption that a television programme would have only one sound channel@ transmitted using a frequency-modulation sub-carrier positioned at the inter-carrier spacing of the television system used in the service area under consideration. Nevertheless@ the WARC-BS-77 did not exclude the use of modulation signals having different characteristics@ provided that the use of those different characteristics did not result in greater interference than that caused by the system considered in the Plan.