Abstract
In fiber optic communication channels, several analog and digital methods are utilized to convey data in order to improve performance and simplify installation. Various digital modulation methods increase tolerance to transmission defects and promote spectral efficiency. In this study, a comparative comparison of several digital modulation formats both inside and outside of 100 Gbps is reviewed. An overview of several transmission methods that can send massive amounts of data at bit rates of up to 1 Tb/s or more. In this particular article, we examine the benefits of digital modulation forms over traditional analog modulation formats using a comparative tabular approach.