concept of single-sideband modulation (SSB) 

Single-Sideband Modulation (SSB) is a type of amplitude modulation (AM) that improves bandwidth efficiency by transmitting only one of the sidebands (either the upper or the lower) and suppressing the carrier signal. This reduces the bandwidth used by half compared to conventional AM, leading to more efficient use of the spectrum and better signal-to-noise ratio. SSB is commonly used in long-distance communication, such as amateur radio and aviation communications.