To study SSB-SC Demodulation & observe the demodulated wave by changing LPF gain & frequency.
Single-sideband modulation (SSB) or Single-sideband suppressed-carrier (SSB-SC) is a refinement of amplitude modulation that more efficiently uses electrical power and bandwidth. Amplitude modulation produces a modulated output signal that has twice the bandwidth of the original baseband signal. Single-sideband modulation avoids this bandwidth doubling, and the power wasted on a carrier, at the cost of somewhat increased device complexity and more difficult tuning at the receiver.
The baseband or modulating signal can be recovered from the SSB-SC signal by using the synchronous detection. Coherent Demodulation of SSB signals ΦSSB (t) is multiplied with cos(ωc t) and passed through low pass filter to get back the original signal.
A true SSB demodulator must have the ability to select sidebands. All the methods of SSB generation so far discussed have their counterparts as demodulators. In this experiment you will be examining the phasing-type demodulator, shown in Fig.1.
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