hi gokul boro,
Real SSB iS difficult to implement in the optical domain. In addition, simulations of the transmission of pseudo-random bit patterns with large extinction ratio for the modulation, which is the way AM modulation is usually done in optical systems, show that pure SSB modulation may not be the best solution.
However, the three VSB modulation embodiments of the appara-tus according to the invention to be described below, give a significant improvment of the achievable transmission distan-ce.
i have attached a pdf file …hope it may help