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:Lasers and deformable mirrors arnt expensive

[neochubbz]

The real beast isn't the labor and cost of laying the line, its the legal nightmare of researching and purchasing the right-of-way. First, you have to run title to determine who owns the right of way, then you negotiate with each property owner, and any one of these property owners can object, causing you to reroute your line.

The Old is New again

[DumbSwede]

45+ years ago when I was a kid and before cellphone towers dotted the landscape there were these funnel shaped microwave repeating towers everywhere that carried long distance phone traffic across the country without wires.

Re:The Old is New again

[Charliemopps]

45+ years ago when I was a kid and before cellphone towers dotted the landscape there were these funnel shaped microwave repeating towers everywhere that carried long distance phone traffic across the country without wires.

I've worked for just about every phone company... We still have them... everywhere. Fibers replaced microwave in most residential areas... but in areas where you can't dig a trench, we use microwave. Communities on islands, on mountain sides... etc... there are a LOT of microwave dishes along the grand canyon for example. Even in sky rises, a lot of companies will setup microwave dishes in an extra conference room and beam a trunk to another building across the way.

The problem with microwave is that it doesn't work well in humidity. Fog, snow and rain make it cut in and out. Basically, imagine your DishNetwork/DirectTv signal... it's got pretty much the same problem.

Re:Lasers and deformable mirrors arnt expensive

[BenFranske]

If it was for base connectivity I would be very surprised if fiber wasn't laid. I am more likely to believe the military use for this was designed for something which can be setup quickly in forward operating locations. Fiber takes time and substantially more infrastructure to install. Theoretically this could be run off a steerable pop-up mast which could be setup in minutes.

Imminent Domain

[TechyImmigrant]

Most property already has utility easements unless they're very rural, even then it's simple enough to seize with Imminent Domain for "the greater good"

Is the domain about the happen any time now?

(Vorsicht vor den Vögel!) damn birds

[smoothnorman]

A few university set-ups in Germany tried this, (e.g. Hamburg), albeit probably with far simpler specifications as it was some years ago. They had surprisingly frequent problems with birds; birds perching on the towers, birds flying between the source/sink, uzw. Packet loss got enough at one point to contact a local falconer to see if his bird of prey could scare them away. It turned out that the local bakery was too much of a draw. There was whimsical talk of adding a TCP/IP error for bakery janitorial events. I believe they eventually just went with fiber pulled through the sewers ..ja-da

Re:Yes, it could be much cheaper

[DoofusOfDeath]

Fiber optic is trivial to tap. Almost as easy as analog phone lines.

Anything is easy to tap, at least in the U.S.

Step 1. Mislead a FISA court about the need. After all, those being tapped will never find out, let alone have a chance to contest the evidence. It's a secret.

Step 2. Find some ISP in the communications path, and hit them with a National Security Letter. Because, you know, fuck the Fourth Amendment. Threaten them with going to jail for even bringing up the issue in court. Again, because, well, fuck being the land of the free, since it's no longer the home of the brave.

Step 3. Do whatever you want. If it violates the law, you can count on some combination of sovereign immunity, prosecutorial descretion, and Presidential pardons to make sure you never face justice while on this earth.

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.