Predistortion linearization of directly modulated DFB lasers and external modulators for AM video transmission

Improved direct-modulation characteristics of a semiconductor laser by FM/IM conversion through an interferometer

“…Unfortunately, the inherent nonlinearities of the light sources produce distortions that limit the performances of the overall system. It seems most difficult Manuscript to implement an equalization circuit to compensate for the generated harmonics and intermodulation products (IMP's), even if the existing alternatives, such as electronic predistortion or feedforward compensation techniques, have allowed a nonnegligible improvement of the laser linearity [7] and [8].…”

Reduction of nonlinear distortion in directly modulated semiconductor lasers by coherent light injection

“…The main impairment of feedforward compensation is the difficulty of generating an accurate error signal. Another solution is based on predistortion, a method that consists of passing the modulation current through an adequate nonlinear element such that when the modified input signal is applied to the laser, an undistorted output results [14]. The main disadvantage with predistortion is the complexity of the electrical circuit to be designed and the difficulty of controlling the harmonics and IMD's at the same time.…”

Polymer-Based Hybrid-Integrated Photonic Devices for Silicon On-Chip Modulation and Board-Level Optical Interconnects

“…However, laboratory test results in most literatures are frequently presented assuming the noise floor at -160dBm considering the typical fiber-optic link parameters [50][51][52]. By using -160dBm as noise floor, our measured SFDR is within 110±3dB/Hz 2/3 over the modulation frequency range 2-8GHz, as shown in Fig.…”