Indirect Line-Of-Sight Free-Space Optical Communications Using Diffuse Reflection

Free-space optical communications (FSOC) has been proved to achieve the highest data rate in wireless communications, and yet, its long-time adoption remains reserved for a very selective set of applications. A culprit of the limited adoption of FSOC is its point-to-point link setup used by this technology as a result of the required a) the direct Line-of-Sight (LOS) between transmitter and receiver, and b) the needed fine alignment of the transceivers of the communicating stations. Indirect LOS FSOC (ID-FSOC) is an alternative to FSOC where transmitter and receiver might not be in LOS of each other but to a diffuse reflector (DR). Such a reflector not only helps to cover out-of-sight areas but also converts the optical link onto a broadcast channel where one station may communicate with all other stations that may have LOS to the reflector. Here, we discuss some of the properties of this novel paradigm and argue that it may represent a new facet of free space of optical communications that provides a great range of applications for high-speed data communications.