DARPA planning 100 Gbps wireless

Seeks interest in development and demonstrations


DARPA (the Defense Advanced Research Projects Agency) has decided that the 200-276 Mbps wireless technology currently used for military communications, known as the Common Data Link, is not going to live forever, and is inviting companies to submit proposals to boost battlefield wireless to an impressive-if-achieved 100 Gbps.

The agency is hosting a “proposers’ day” event in January 2014. It says its Broad Agency Announcement (BAA) will set out the details of its “100G” program, “with the objective to design, build, and test a communications link with fiber-optic-equivalent capacity, long reach, and high availability in airborne-to-airborne and airborne-to-ground configurations that can serve as a deployable data backbone in a military communications network.”

The communications platform would have to match the weight and power specifications of today’s CDL platforms, and provide 200 Km reach for air-to-air links and 100 Km for air-to-ground links.

Since the platform has to operate in all weather conditions, the simplest solution – free-space optics – is ruled out.

DARPA’s media release quotes program manager Dick Ridgeway as saying “Providing fiber-optic-equivalent capacity on a radio frequency carrier will require spectrally efficient use of available RF spectrum … 100G plans to demonstrate how high-order modulation and spatial multiplexing can be synergistically combined to achieve 100 Gigabits per second”.

If, as speculated at ExtremeTech, the 100G program is likely to use Ku-band frequencies, then WiFi’s spectral efficiency of around 11 bits per Hertz doesn’t come even close to 100G’s requirements. The widest transmission allocation in the Ku band in Australia (since that’s the database this writer is familiar with) is 550 Mhz, yielding around 6 Gbps at WiFi rates.

Turning the calculation the other way: at the spectral efficiency of current commercial-grade kit, 100 Gbps would need a radio channel wider than the entire Ku-band, at 9 GHz. Hence the additional attention on spatial multiplexing.

So while there’s no prospect that DARPA is about to render optical fibre obsolete, The Register would anticipate some interesting science to flow from the project. ®

Similar topics


Other stories you might like

  • DARPA wants to refuel drones in flight – wirelessly
    Boffin agency seeks help to shoot 100kW through the air with lasers, but contributors don't have long to deliver

    US military researchers are trying to turn in-flight refueling tankers into laser-shooting "airborne energy wells" for charging drones, and they want the public's help to figure out how.

    The Defense Advanced Research Projects Agency (DARPA) published a request for information (RFI) from anyone willing and able to contribute their tech, with a few caveats. It needs to fit on existing in-flight refueling tankers (the newer KC-46 and Cold War-era KC-135, specifically) and be able to deliver 100kW of power.

    Militaries around the world have been using in-flight refueling for decades to extend aircraft patrols and long-range missions. With a history of development stretching back to the 1920s, the practice has since developed into a standard part of operating an air fleet powered by aviation fuel.

    Continue reading
  • DARPA backs virtual worlds for autonomous off-road vehicles
    Intel and co outline Holodeck-like efforts for combat bots

    Intel has shed some light on its participation in a DARPA program set up to aid the development of autonomous combat vehicles that can go off road. 

    The x86 giant on Tuesday outlined its involvement in the US government agency's Robotic Autonomy in Complex Environments with Resiliency – Simulation (RACER-Sim) project.

    RACER-Sim is part of DARPA's wider RACER program to foster the advancement of self-driving machines that can keep up with human-controlled vehicles over tough terrain amid conflict and other real-world situations. RACER-Sim, as its name suggests, involves the creation of simulations in which these autonomous systems can be developed and tested before being tried out in the real world. That's useful because it's a good idea to perfect the code as much as possible in a virtual world, where it can do no actual harm or damage, before putting it behind the wheel of pricey and dangerous hardware.

    Continue reading
  • DARPA says US hypersonic missile is ready for real world
    A new arms race emerges

    DARPA announced a second successful test of its hypersonic cruise missile, adding that the weapon, capable of speeds in excess of Mach 5, is ready for real-world use. 

    DARPA has been testing hypersonic weapons for several years. The program in question, called the Hypersonic Air-breathing Weapon Concept (HAWC), began in 2016 with Raytheon as a partner. Raytheon's HAWC first flew in 2021, and this latest test used a design manufactured by Lockheed Martin and Aerojet Rocketdyne.

    Hypersonic weapons are any missile that travels at Mach 5 or faster, but with an added caveat: they can be controlled. Traditional missiles often exceed Mach 5 as well, but can't be steered once they're launched. 

    Continue reading

Biting the hand that feeds IT © 1998–2022