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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. The sidebands carry the information transmitted by the radio ...
The carrier frequency is 1.25 MHz above the lower edge of the 6 MHz wide channel. This effectively makes the system AM at low modulation frequencies and SSB at high modulation frequencies. The absence of the lower sideband components at high frequencies must be compensated for, and this is done in the IF amplifier.
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.
A subcarrier is a sideband of a radio frequency carrier wave, which is modulated to send additional information. Examples include the provision of colour in a black and white television system or the provision of stereo in a monophonic radio broadcast.
If digital single-sideband modulation is used, the passband signal with bandwidth W corresponds to a baseband message signal with baseband bandwidth W, resulting in a maximum symbol rate of 2W and an attainable modulation efficiency of 2N (bit/s)/Hz. Example 3: A 16QAM modem has an alphabet size of M = 16 alternative symbols, with N = 4 bit ...
A side band or sideband can refer to: Side project , in music Sideband , in communications, either of the two bands of frequencies, one just above and one just below a carrier frequency, that result from modulation of a carrier wave
Vestigial sideband modulation (VSB) is a modulation method which attempts to eliminate the spectral redundancy of pulse-amplitude modulation (PAM) signals. Modulating a carrier by a real-valued data sequence results in a sum and a difference frequency, resulting in two symmetrical carrier side-bands.
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).