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Network Communications Networking The Military Wireless Networking Technology

DARPA Begins Work On 100Gbps Wireless Tech With 120-mile Range 83

MrSeb writes "DARPA has begun development of a wireless communications link that is capable of 100 gigabits per second over a range of 200 kilometers (124mi). Officially dubbed '100 Gb/s RF Backbone' (or 100G for short), the program will provide the U.S. military with networks that are around 50 times faster than its current wireless links. In essence, DARPA wants to give deployed soldiers the same kind of connectivity as a high-bandwidth, low-latency fiber-optic network. In the case of Afghanistan, for example, the U.S. might have a high-speed fiber link to Turkey — but the remaining 1,000 miles to Afghanistan most likely consists of low-bandwidth, high-latency links. It's difficult (and potentially insecure) to control UAVs or send/receive intelligence over these networks, and so the U.S. military instead builds its own wireless network using Common Data Link. CDL maxes out at around 250Mbps, so 100Gbps would be quite a speed boost. DARPA clearly states that the 100G program is for US military use — but it's hard to ignore the repercussions it might have on commercial networks, too. 100Gbps wireless backhaul links between cell towers, rather than costly and cumbersome fiber links, would make it much easier and cheaper to roll out additional mobile coverage. Likewise, 100Gbps wireless links might be the ideal way to provide backhaul links to rural communities that are still stuck with dial-up internet access. Who knows, we might even one day have 100Gbps wireless links to our ISP."
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DARPA Begins Work On 100Gbps Wireless Tech With 120-mile Range

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  • by mcgrew ( 92797 ) * on Monday December 17, 2012 @01:16PM (#42315149) Homepage Journal

    I don't know why I'm responding since you're AC and won't see it, but if someone else is wondering the same thing, you can hear an FM radio broadcast for a couple hundred miles in some conditions. That radio station has a 50,000 watt transmitter, but the power drops off inversely. By the time it reaches your property it's only milliwatts.

  • by Baloroth ( 2370816 ) on Monday December 17, 2012 @01:48PM (#42315415)

    This is so much pie-in-the-sky bullshit I can't even believe it. I hear about this kind of thing year after year, and it never happens.

    This is DARPA, a company for whom "aim at the sky" is more of a directive rather than a metaphor. Some of there other work includes flying tanks, passive radar systems, stealth ships, onion routing, and wide area interconnected computer networks. Most of it doesn't work, of course... but when it does, we get something no one else would have bothered developing.

  • by Anonymous Coward on Monday December 17, 2012 @01:51PM (#42315449)
    "Defence []" is [] perfectly [] acceptable [].
  • by CaptainNerdCave ( 982411 ) on Monday December 17, 2012 @02:53PM (#42316143)

    The problem that was already addressed is the curving of earth, because it can be overcome with height. Let's sustain that increasing the altitude of your dishes will allow greater distance without the sphere's shape interfering, you still have all of the factors associated with those heights: weather, cost of getting there, service, general maintenance.

    Maintenance: How easy is it to remove ice? Snow? What about the cost of maintaining the tower?

    Service: What do you do when you can't communicate with the unit, and you've ruled out everything except the cable between the unit and it's nearest point of contact?

    Cost: This is a broader issue than maintenance, because it allows for not owning the tower/building. Tower space is premium, building roof-tops are premium, labor to install, service, or repair is EXTRA premium. Not only do you need guys willing to climb 200+ feet, but they need to be technically capable. [] charges no less than $250/hr.

    Weather: Why don't you see point-to-point connections on towers that are 200ft up on towers? Because the bandwidth requires very high frequencies, and those frequencies are very susceptible to any movement caused by wind. I've seen a gentle breeze (on the ground) turn a wireless link from -45 dbi to -60. Let's not forget rain and snow.

    The only good ways to mount an antenna or dish at a height, and ensure reliability, are with a very large antenna (think something with 3 or 4 legs and covering at least 400 feet^2), or a building.

  • Re:120 mile range? (Score:4, Informative)

    by Eevee ( 535658 ) on Monday December 17, 2012 @03:00PM (#42316235)
    Well, if Slashdot ever bothered linking to the original article [], you'd see:

    The goal is to create a 100 Gb/s data link that achieves a range greater than 200 kilometers between airborne assets and a range greater than 100 kilometers between an airborne asset (at 60,000 feet) and the ground.

Our business in life is not to succeed but to continue to fail in high spirits. -- Robert Louis Stevenson