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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.
Although average power is the same as PEP for complex modulation forms, such as FSK, the peak envelope power bears no particular ratio or mathematical relationship to longer-term average power in distorted envelopes, such as a CW waveform with power overshoot, or with amplitude modulated waveforms, such as SSB or AM voice transmissions. Typical ...
MCW on AM would typically be sent as double-sideband amplitude modulation, with one channel containing digital information, and using a subcarrier, also known as A2A.For example, Morse code sent by in an AM broadcast by a commercial radio station would be modulated CW as it contains a subcarrier.
Signalling by keying the carrier directly, a.k.a. continuous wave (CW) or on–off keying, currently used in amateur radio. This is often but not necessarily Morse code. A2A Signalling by transmitting a modulated tone with a carrier, so that it can easily be heard using an ordinary AM receiver.
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.
Continuous wave (CW) is on-and-off keying of a sine-wave carrier, used for Morse code communications and Hellschreiber facsimile-based teleprinter transmissions. It is a data mode, although often listed separately. [25] It is typically received via lower or upper SSB modes. [23]
With a large antenna system like a long yagi, and higher power (typically 100 watts or more) contacts of around 1 000 km (600 miles) using the Morse code (CW) and single-sideband (SSB) modes are common. Ham operators seek to exploit the limits of the frequencies usual characteristics looking to learn, understand, and experiment with the ...
The power of an AM radio signal plotted against frequency. fc is the carrier frequency, fm is the maximum modulation frequency. In radio communications, a sideband is a band of frequencies higher than or lower than the carrier frequency, that are the result of the modulation process.