Military Laser/Radio Tech Proposed As Alternative To Laying Costly Fiber Cable

An anonymous reader writes "Californian comm-tech company Aoptix is testing new laser+radio hybrid communications technology with three major U.S. internet carriers. The equipment required can be bolted onto existing infrastructure, such as cell-tower masts, and can communicate a 2gbps stream over 6.5 miles. The system was developed over 10 years at a cost of $100 million in conjunction with the Air Force Research Laboratory, and the military implementation of it is called Aoptix Enhanced Air Ground Lasercom System (EAGLS). The laser component of the technology uses a deformable mirror to correct for atmospheric distortion over the mast-hop, in real-time. The laser part of the system is backed-up by a redundant radio transmitter. The radio component has low attenuation in rainy conditions with large refracting raindrops, while the laser is more vulnerable to dense fog. The system, which features auto-stabilization to compensate for cell-tower movement and is being proposed as an alternative to the tremendous cost p/m of laying fiber cable, is being tested in Mexico and Nigeria in addition to the three ISP trials.

Comments

Rain attenuates the radio signal

[duckintheface]

The OP says that "The radio component has * low attenuation* in rainy conditions with large refracting raindrops". I think they mean "high attentuation". TFA says that radio is disrupted by rain.

Re:Yes, it could be much cheaper

[mlts]

L1 encryption could be quite brain-dead simple. One could use preshared keys and call it done (with an algorithm to use session keys derived from D-H sessions encrypted by the "master" PSK, and change every so often.)

I've wondered why communications lasers are not more often used, especially IR ones.