Difference between BSS and FSS?

These are official ITU terms used to describe radio services operating in particular allocated frequency bands.

Abbreviation : BSS
Term : Broadcasting Satellite Service
Definition : A radio communication service in which signals transmitted or retransmitted by space stations are intended for direct reception by the general public.

Abbreviation : FSS
Term : fixed-satellite service  
Definition : A radiocommunication service between earth stations at given positions, when one or more satellites are used; the given position may be a specified fixed point or any fixed point within specified areas; in some cases this service includes satellite-to-satellite links, which may also be operated in the inter-satellite service; the fixed-satellite service may also include feeder links for other space radiocommunication services.

FSS came first with operation in C band. Then came Ku band operation (also being called FSS).  Then, in 1977, came a BSS conference that, for political reasons, allocated every country some satellite orbit position and some frequency in the upper part of Ku band in circular polarisation intended specifically for broadcasting.  This grand plan was taken up by a few countries and the term BSS was born. The plan soon fell into disuse however with increasing satellite powers and anywhere in Ku band (and C band) began to be used for direct to home broadcast type services.  BSS refers to services transmitted by satellite in specific frequency bands: 11.7-12.2 GHz in ITU Region 3 (Asia, Australia), 10.7 - 12.75 GHz in ITU Region 1 (Europe, Russia, Africa), and 12.2-12.7 GHz ITU Region 2 (North and South America).

Best regards, Eric

Video (satellite TV) is transmitted in both FSS and BSS bands.

Look in Lyngsat at Astra at 19.2 East and you will see that they transmit broadcast TV and audio across the entire Ku band from 10.7 to 12.75 GHz.

The grandiose world BSS plan of 1977 is now history and I'm not sure if there are any operational satellites remaining which operate the BSS circular polarisation Ku band (analogue FM-TV) at pre-planned orbit positions.

Best regards, Eric.