Merits of VSB

The main advantage of VSB modulation is the reduction in bandwidth. It is almost as efficient as the SSB .

Due to allowance of transmitting a part of lower sideband, the constraint on the filter have been relaxed . So practically, easy to design filters can be used.

It possesses good phase characteristics and makes the transmission of low frequency components possible .

Demerits of VSB

A small portion of the transmitter power is wasted in the vestigial sideband filters which remove the remaining lower sideband.

The attenuation slope of the receiver to correct the boost at lower video frequencies introducing a loss of about 6 db in the signal to noise voltage ratio.

Some phase and amplitude distortion of the picture signal occurs because of filter and IF stage.

More critical tuning at the receiver becomes necessary because for a given amount of local oscillator mismatch or drift after initial tuning, the degeneration of picture quality is less with wider lower sideband than with narrow lower sideband.