Phase-Retrieval for Short-Reach IM/DD Links

With short-range optical communication links emerging in many fields of applications, the design of appropriate low-complexity transceivers has posed a major challenge in recent years. Since state-of-the-art coherent transceivers are less favorable due to their high complexity, simpler and more cost-efficient solutions are needed. Noncoherent transceivers using intensity modulation (IM) at the transmitter and direct detection (DD) at the receiver have become prominent, as they provide reduced complexity, cost and power consumption. Generally, the use of simplified hard- ware components entails performance penalties, which need to be compensated by signal processing routines. Starting from the Nonlinear Schrödinger Equation (NSE), we consider a short-reach optical link, with chromatic dispersion (CD) being the only impairment. We continue with a suitable system model for a noncoherent IM/DD system and notice that the removal of CD can be reformulated as a phase retrieval problem, which is well studied in various scientific areas. Finally, we will compare the performance of different equalizers for phase retrieval based on their achievable rates.     «

With short-range optical communication links emerging in many fields of applications, the design of appropriate low-complexity transceivers has posed a major challenge in recent years. Since state-of-the-art coherent transceivers are less favorable due to their high complexity, simpler and more cost-efficient solutions are needed. Noncoherent transceivers using intensity modulation (IM) at the transmitter and direct detection (DD) at the receiver have become prominent, as they provide re...     »