Testing Optical Systems with Simulated OFDM Signals
Applikationsberichte
Orthogonal frequency-division multiplexing (OFDM) has become widely used for wideband digital communication in wired and wireless systems. Recently, it has also attracted the attention of researchers developing long-haul optical transmission systems.
In optical applications, OFDM has the capability to overcome a variety of limitations commonly associated with optical transmission systems: modal dispersion, relative intensity noise, chromatic dispersion, polarization mode dispersion, and self-phase modulation. Attracted by these inherent advantages, researchers are experimenting with two forms of OFDM in optical systems: coherent-optical OFDM (CO-OFDM) and direct-detected optical OFDM (DDO-OFDM).
The main differences between CO-OFDM and DDO-OFDM are in the ways optical signals are generated and received. For example, a typical CO-OFMD architecture uses in-phase/quadrature (I/Q) modulation with coherent detection. In contrast, a typical DDO-OFDM architecture uses single-sideband (SSB) transmission and direct detection.