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In radio communications, single-sideband modulation (SSB) or single-sideband suppressed-carrier modulation (SSB-SC) is a type of modulation used to transmit information, such as an audio signal, by radio waves. A refinement of amplitude modulation, it uses transmitter power and bandwidth more efficiently.
Transmission in which only one sideband is transmitted is called single-sideband modulation or SSB. SSB is the predominant voice mode on shortwave radio other than shortwave broadcasting. Since the sidebands are mirror images, which sideband is used is a matter of convention.
CESSB (controlled-envelope single-sideband) is a narrowband modulation method using a single sideband, whose peak envelope level is controlled so that the peak-to-average power ratio of CESSB is much reduced compared to standard SSB modulation and offers improved effective range over standard SSB modulation while simultaneously retaining backwards compatibility with standard SSB radios.
Single-sideband modulation with full carrier (e.g. as used by CHU) J: Single-sideband with suppressed carrier (e.g. Shortwave utility and amateur stations) K: Pulse-amplitude modulation: L: Pulse-width modulation (e.g. as used by WWVB) M: Pulse-position modulation: N: Unmodulated carrier (steady, single-frequency signal) P: Sequence of pulses ...
Most amateur digital modes are transmitted by inserting audio into the microphone input of a radio and using an analog scheme, such as amplitude modulation (AM), frequency modulation (FM), or single-sideband modulation (SSB). Amateur teleprinting over radio (AMTOR) D-STAR (Digital Data) a high speed (128 kbit/s), data-only mode.
Reduced-carrier transmission is an amplitude modulation (AM) transmission in which the carrier signal level is reduced to reduce wasted electrical power. Suppressed-carrier transmission is a special case in which the carrier level is reduced below that required for demodulation by a normal receiver.
Although transmissions are often single sideband (SSB), the use of the ALE transmission mode is more and more common. HFGCS complements the use of satellite communications between aircraft and ground stations. Stations of the HFGCS Network [1] Andersen Global, Andersen Air Force Base, Guam, USA
Independent sideband (ISB) is an AM single sideband mode which is used with some AM radio transmissions. Normally each sideband carries identical information, but ISB modulates two different input signals — one on the upper sideband, the other on the lower sideband. This is used in some kinds of AM stereo (sometimes known as the Kahn system).