
Robust Optical Wireless Link for the Backhaul and Fronthaul of Small Radio Cells
Author(s) -
Dominic Schulz,
Volker Jungnickel,
Christos Alexakis,
Michael Schlosser,
Jonas Hilt,
Anagnostis Paraskevopoulos,
Liane Grobe,
Peter Farkas,
Ronald Freund
Publication year - 2016
Publication title -
journal of lightwave technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.346
H-Index - 200
eISSN - 1558-2213
pISSN - 0733-8724
DOI - 10.1109/jlt.2016.2523801
Subject(s) - communication, networking and broadcast technologies , photonics and electrooptics
This paper summarizes recent work on the use of optical wireless links as a robust outdoor backhaul solution for small radio cells, such as WiFi, LTE and 5G, over distances between 20 and 200 m. Results of a 5-month outdoor field trial in Berlin, Germany, indicate that the visibility range was never below 180 m, with more than 1 km in 99% of all times during this period. Rate-adaptive transmission proved to improve the availability remarkably in the occasional presence of fog or sunlight. A mathematical model of the backhaul link including these impairments is presented and implemented to obtain an optimized link design. A prototype was realized, accordingly, using low-cost optoelectronic components and a 1 Gb/s baseband chipset. Gross data rates of 800, 500, and 225 Mb/s have been achieved in real-time operation over 20, 100, and 215 m outdoor link distance, respectively, with 2 ms latency at 95% load. Finally, we discuss further evolution towards 5G mobile networks.