A new technology called Laser-Radio, with the trade name "AOptix Intellimax" from AOptix (Campbell, CA), combines free-space optical (FSO) communications (or as termed by AOptix, Advanced Optics) with millimeter-wave radio-frequency (RF) for a wireless solution that improves over pure FSO and even optical-fiber-based communications networks.
The Laser-Radio technology transmits a 2 Gbit/s data stream redundantly over both the optical and radio interfaces, and then at the receiving end compares and combines the best data at the bit level from both frequencies in real time. The optical side of the technology runs at 1550 nm with an output power of 120 mW and the radio-frequency portion runs at 70–80 GHz with a transmit power of 80 mW. AOptix calls the pairing of these two wavelengths "Advanced Wavelength Diversity," and maintains that by using two very different technologies in combination, they are able to better withstand the weather issues that are typically problematic for any type of wireless transmission. The algorithms used at the receiving end to parse out the healthiest bits of data from each transmission stream were developed during the company's earlier work with the U.S. military when they created a "wireless network in the sky" between multiple airborne platforms—long before the advent of Google Loon or Facebook Drones.
While optical-fiber communications are the preferred standard between super macro cell-tower backhaul applications requiring 1 to 10 Gbit/s capacity, AOptix's Laser-Radio technology addresses the 500 Mbit/s to 2 Gbit/s macro cell aggregation backhaul for 4G and even emerging 5G wireless applications. While the ability to provide a 2 Gbit/s data stream at distances up to 8 km is within the capabilities of many FSO networks, Laser-Radio technology achieves these specifications and adds RF to deliver data at a bit-error-rate (BER) of < 10-9 through fog, rain, snow, heavy wind, and other severe weather conditions. Furthermore, it can tolerate up to 3° of twist and sway caused by heavy winds and ground vibrations and, like pure FSO, is deployed on towers in a matter of hours versus months for fiber-optic trenching. Reference: http://pages.aoptix.com/download-mobile-backhaul-brief.html.