High Bitrate Data Transmission in the 8-14 µm Atmospheric Window Using An External Stark-Effect Modulator With Digital Equalization

Optics Express 2023
Dely Hamza, Joharifar Mahdieh, Xiaodan Pang, Gacemi Djamal, Toms Salgals, Richard Schatz, Sun Yan-Ting, Thomas Bonazzi, Etienne Rodriguez, Yankov Todarov, ANgela Vasanelli, Aleksejs Udaļcovs, Sandis Spolītis, Vjačeslavs Bobrovs, Oskars Ozoliņš, Sergei Popov, Carlo Sirtori

High bitrate mid-infrared links using simple (NRZ) and multi-level (PAM-4) data coding schemes have been realized in the 8 µm to 14 µm atmospheric transparency window. The free space optics system is composed of unipolar quantum optoelectronic devices, namely a continuous wave quantum cascade laser, an external Stark-effect modulator and a quantum cascade detector, all operating at room-temperature. Pre- and post-processing are implemented to get enhanced bitrates, especially for PAM-4 where inter-symbol interference and noise are particularly detrimental to symbol demodulation. By exploiting these equalization procedures, our system, with a full frequency cutoff of 2 GHz, has reached transmission bitrates of 12 Gbit/s NRZ and 11 Gbit/s PAM-4 fulfilling the 6.25 % overhead hard-decision forward error correction threshold, limited only by the low signal-to-noise ratio of our detector.

DOI
10.1364/OE.474209
Hyperlink
https://opg.optica.org/oe/fulltext.cfm?uri=oe-31-5-7259&id=526177

Hamza, D., Mahdieh, J., Pang, X., Djamal, G., Salgals, T., Schatz, R., Yan-Ting, S., Bonazzi, T., Rodriguez, E., Todarov, Y., Vasanelli, A., Udaļcovs, A., Spolītis, S., Bobrovs, V., Ozoliņš, O., Popov, S., Sirtori, C. High Bitrate Data Transmission in the 8-14 µm Atmospheric Window Using An External Stark-Effect Modulator With Digital Equalization. Optics Express, 2023, Vol. 31, No. 5, pp.7259-7264. e-ISSN 1094-4087. Available from: doi:10.1364/OE.474209

Publication language
English (en)