The basic optical receiver consists of a photodetector to convert the optical signal into a current, a low-noise preamplifier to convert and amplify the current into a voltage, an optional low pass filter to shape the received pulse or limit the bandwidth and a high-gain. The basic optical receiver consists of a photodetector to convert the optical signal into a current, a low-noise preamplifier to convert and amplify the current into a voltage, an optional low pass filter to shape the received pulse or limit the bandwidth and a high-gain. In an optical transmission system, one essential parameter in determining the system power budget is the optical receiver sensitivity, which is defined as the minimum average optical power for a given bit error rate (BER). To make a good optical receiver design, it is critical to understand the. al receiver analog front end, where low power operation is a primary consideration with a goal of supporting 56 Gbaud intensity modulated direct detect transceivers. Note :Operation beyond these absolute maximum conditions may degrade device performance, lead to device failure, shorter. the design of optical receivers. As signals travel in a fiber, they are attenuated and distorted, and it is the function of the receiver circuit at the other side of the fiber to generate a clean electrical signal from th l signal to an electrical signal. However, the signal gen-erated by a.