Published on July 25th, 2011 | by Alexis Argent0
OnLive Creator Designs Revolutionary Wireless System
The incubator that gave life to cloud gaming company OnLive has unveiled DIDO, a technology that its creators believe can basically eliminate wireless interference in Wi-Fi and 3G through cloud processing. Steve Perlman, the man who invented Microsoft’s WebTV and established OnLive as a “this will never work” startup into a viable competitor for the console gaming space published the details of DIDO in a white paper, which was distributed to reporters. In the white paper, Perlman said he envisions cloud gaming and other related technologies that could work on airplanes and other locations, all connected seamlessly. And he makes one provocative statement for gaming fans, too:
“When OnLive servers are co-located with DIDO servers, there is unprecedented low latency, to the point where remote-hosted OnLive gaming and computing is lower latency than the same games and applications running on a local device,” Perlman wrote – in other words, DIDO is faster than a game running on a native console or PC. DIDO should have a latency of just a millisecond, he wrote. “We believe DIDO wireless will completely transform the world,” Perlman added.
How does it work?
In a nutshell, Wi-Fi or 3G signals work best when a PC or a wireless device is all alone on a network, whether it be near a Wi-Fi access point or a cell-phone antenna tower. Introduce more devices, and the wireless packets that contain data get split up – one for me, one for you – degrading the bandwidth further. If 100 users simultaneously surround a Wi-Fi point and all of them ask for data at the same time, with the same level of priority, then the total available bandwidth is 1/100th of the peak level.
DIDO claims to break Shannon’s Law, which defines the maximum amount of error-free data rate that can be transmitted through a single communications channel for given amount of spectrum and noise level.
DIDO’s magic, however, is how it transmits the data.
In a normal Wi-Fi or cellular radio, the data packet is transformed into a radio signal wave form across the same frequency. The radio inside a PC or phone then demodulates the data back into bits, and into a file that can be played back or otherwise accessed.
Interference from multiple PCs or phones, of course, causes that wave to be modified. Instead of a wave representing a single datastream, that wave represents the sum of all the data packets, and it’s up to the PC or cellular radio to figure out which part of the wave is its own data packet.
What DIDO does, according to the white paper, is cut out the intelligence from the radios, both on the PC and access point, and replace them with an incredible amount of computing in the cloud – which, of course, OnLive has already populated with its own servers. Instead of the access point creating the waveform, a so-called DIDO data center creates the radio signal and sends it along a wired connection. The access point simply broadcasts the signal.
Through some incredibly complex mathematics and some test signals in the handshake process, what DIDO does is this: it creates a radio signal, that at each antenna of each user’s device, produces an independent waveform for each device with only that device’s data. In some ways, it’s like a speaker with a voice so perfectly modulated that he could be heard by every person at a crowded bar, even if those people were all speaking at once.
And, according to Perlman, it works. DIDO has been tested at frequencies from 1 MHz to 1 GHz, he wrote, and actually improves if the signals overlap.
Perlman also tested a 3- to 7-MHz version of DIDO (called DIDO Rural) that bounces off the ionosphere. The “near-vertical incidence Skywave” should have a radius of about 250 miles; in practice, it worked at up to 32.9 miles away, Perlman wrote in the white paper. It should have about 2 to 3 milliseconds of latency.
Some online commenters grumbled that DIDO is just a twist on another wireless technique, known as multi-user MIMO. Perlman was not immediately available to comment.
But Perlman also ended his white paper with a bang: “Eventually—and unlike everything else in this white paper, this remains to be demonstrated, but I’m confident it is achievable—there will be no physical display screen, speakers or input device, but rather we’ll see, hear and interact with a panoramic 3D experience that can be all around us whenever and wherever we want it to be, all created and transmitted reliably and instantly from the cloud.”