Single SideBand modulation
Abbreviated as SSB, Single SideBand modulation is a type modulation that eliminates all components of one sideband from an amplitude-modulated wave. SSB was used for long distance telephone communications. It consisted of groups of telephone conversations modulated on upper and/or lower sidebands of contiguous suppressed carriers. SSB was also used by the U.S. Air force for communications between nuclear bombers and NORAD, before satellite communications.