Comparison of Intersymbol Interference Power Penalties for OOK and 4-PAM in Short-Range Optical Links

Krzysztof Szczerba; Petter Westbergh; Erik Agrell; Magnus Karlsson; Peter Andrekson; Anders Larsson

doi:10.1109/JLT.2013.2285468

Comparison of Intersymbol Interference Power Penalties for OOK and 4-PAM in Short-Range Optical Links
Artikel i vetenskaplig tidskrift, 2013

We present results of experimental and theoretical investigations of intersymbol interference in 4-PAM transmission in short-range optical communications links based on the power penalty. A test link comprised of a directly modulated 850 nm VCSEL with up to 200 m of multimode fiber and direct detection was used. The link bandwidth was below 10 GHz and the maximum achieved data rate with 4-PAM was 44 Gbps over 100 m of fiber. In the same case and at similar sensitivity, only 32 Gbps could be achieved with OOK. If typical forward error correction could be applied, the sensitivity of the 4-PAM system was improved by up to 4 dB, reaching -10 dBm at 25 Gbps.

ISI

datatransmission

MMF

Intersymbol Interference

Multimode Fiber

VCSEL

datacomm

Vertical Cavity Surface Emitting Laser

PAM

Pulse Amplitude Modulation