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SSB Modulation : Single side band modulation is a type of modulation used to transmit information,such as an audio signal.it uses transmitter power and bandwidth more efficiently. 

Extended single sideband SSB(medium 1)---4khz(bandwidth) ,SSB(wide-2)------6khz(bandwidth)

DSB Modulation: Double-sideband suppressed-carrier transmission DSB-SC is transmission in which frequencies produced by amplitude modulation (AM) are symmetrically spaced above and below the carrier frequency and the carrier level is reduced to the lowest practical level, ideally being completely suppressed. It is a double side band without carrier AM. Bandwidth is 2 fm. Less number of channels in a given frequency range. Moderately difficult reconstruction.