SSB modulation

SSB stands for “Single Sideband“. SSB is a form of amplitude modulation that is used primarily in voice communications, such as in amateur radio, citizens band (CB) radio, and marine radio.

In SSB, the audio signal is first passed through a bandpass filter to select only the range of frequencies that contains the voice information. Then, the audio is used to modulate the amplitude of a carrier signal. However, unlike traditional AM, only one sideband is transmitted.

There are two types of SSB: upper sideband (USB) and lower sideband (LSB). In USB, the upper sideband and the carrier are transmitted, while in LSB, the lower sideband and the carrier are transmitted. The carrier is removed because it is not needed for demodulation, and it contains no useful information. SSB modulation is more spectrally efficient than AM, which means that it uses less bandwidth, and it also has better signal-to-noise ratio.

It is important to note that SSB radios require a more accurate tuning to properly receive a signal, and the received audio may sound different from what you’re accustomed to hearing from an AM radio.