Photodiode nonlinear modeling and its impact on optical links phase noise

Abstract

The photodiode impact on the phase noise of an optical link, and particularly its ability to convert the laser amplitude noise into microwave phase noise, is studied and modeled. The model involves a nonlinear RC cell which describes a photogeneration delay which is a function of the optical power. The whole system is then implemented on a microwave CAD software, and the link gain and phase noise performance are computed.

Coupled optoelectronic oscillators: Design and performance comparison at 10 GHz and 30 GHz

“…A strong correlation between amplitude noise and RF phase noise is observed, possibly due to amplitude to RF phase conversion at the photodiode level. A method to reduce this conversion process has already been proposed in [6] and has been applied for all our phase noise measurements. By adjusting optical power on the photodiode, we obtained a reduction of 15 dB on the phase noise close to the carrier for the EDFA as shown in Fig.…”