An integrated optical receiver for 2.5Gbit/s using 4-PAM signaling

A fully integrated optical receiver with high sensitivity and linearity is presented. The optical receiver implements an integrated large-area photodiode, a transimpedance amplifier, an automatic gain control and linear post amplifiers to have a good linearity with multilevel pulse amplitude modulation (M-PAM). The receiver has a measured sensitivity of -22dBm (BER=10^-9) at 1.25Gbit/s for a binary signal. A data rate of 2.5Gbit/s and a sensitivity of -16dBm (BER=10^-9) are achieved with 4-PAM. Using M-PAM signaling and large-area integrated photodiodes make the optical receiver promising for the small bandwidth large-core step-index plastic optical fiber.