Final answer:
DSB-SC modulation is achieved using a switching modulator by multiplying a message signal with a sinusoidal carrier signal, resulting in a suppressed carrier frequency and two sidebands in the modulated signal.
Step-by-step explanation:
Double Sideband-Suppressed Carrier (DSB-SC) modulation can be performed using a switching modulator, also known as a gate, which is an integral part of communication systems within the field of Electrical Engineering. A switching modulator operates by multiplying the message signal (m(t)) to be transmitted with a carrier signal (c(t)). The carrier signal typically takes the form of a sinusoidal wave, with the general mathematical expression c(t) = Acos(2πfct), where A is the amplitude and fc is the frequency of the carrier wave.
To achieve DSB-SC modulation, the switching modulator turns the carrier on and off at a high switching rate, creating a gated carrier that contains both the original carrier frequency and its inverted form. This gated carrier is then mathematically expressed as a product of the message and carrier signals: s(t) = m(t) × c(t). Since the carrier is sinusoidal, the modulation process produces two sidebands in the frequency domain, each carrying the information of the message signal, but without the carrier frequency itself being transmitted, hence the 'suppressed carrier' terminology.
The use of a switching modulator for DSB-SC provides a more power-efficient transmission since the carrier's energy is not being transmitted. This technique is often employed in television and radio broadcasting, where spectrum and power efficiency are paramount.