Q.What is DSB-SC?

Ordinary AM wastes power (two-thirds sits in the carrier) and bandwidth (two identical sidebands). Since one sideband is an exact image of the other and the carrier carries no information, more economical forms of AM transmit only part of the full signal:

• Double Sideband Suppressed Carrier (DSB-SC) — the carrier is removed and only the two sidebands are sent, saving about $2/3$ of the total power at $m_a = 1$. It is used, for example, to carry two-channel stereo information in FM and TV broadcasting.
• Single Sideband Transmitted Carrier (SSB-TC) — one sideband is suppressed while the carrier and the other sideband are kept, saving about $1/6$ of the power.
• Single Sideband Suppressed Carrier (SSB-SC, or simply SSB) — both the carrier and one sideband are suppressed, so only a single sideband is transmitted, saving about $5/6$ (roughly 83.33%) of the power. …