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mobile mimo and more

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KE2N's picture
mobile mimo and more

sorry for the advertisements, but I like the backpack and mobile demo

AREDN is just shy of doing something like "streamscape" no?


It is possible
NOTE: I only quick glanced the video without audio so please correct any errors you may see below:

Right now one of hte biggest limiting factors will be your local user involvement.

One will note they used according to their notes 17 devices (with what looks like 4 devices to provide the "main" what we would call mid mile or backbone nodes) This is to cover an area that is roughly 1.0-3.0 Square Mile in size (the far peaks of the coverage area shown are around 1.5 miles by 1.5 miles, the main coverage area is around .75 miles x .75 miles roughly)

Nothing (to my knowledge) stopping AREDN from doing this today, it is just an issue of getting enough hardware in place to support it.
K5DLQ's picture
that video was from Oct 2014.
that video was from Oct 2014.  I wonder what new things they have done in the last 2.5yrs?
AE6XE's picture
Looks to me like we're doing
Looks to me like we're doing exactly the same thing, not even shy.    There's only one thing I saw in the product specs that AREDN doesn't really do, that is beam forming.    However, if I put on my best marketing spin hat, I suppose we could claim some aspects of beam forming.   

All the buzz words and features directly apply to AREDN--COFDM, MIMO, MANET, are the 3 primary features they focus on.    All 802.11n radios *are* COFDM and MIMO--they market the technical aspects of 802.11n as if it is all their own without mentioning 802.11n.    AREDN uses OLSR for the Mobile Adhoc Network.   We could literally take all of the marketing material and substitute AREDN and still get a good nights sleep. 

I'd be really interested to know what chipset they do use--with a claim that they don't use standard "wifi" chipsets.   Would likely result in a failed business model if they were trying to develop their own chipset.

K6AH's picture
User Manual

A lot can be gleaned from the SC3500-3800 User Manual:

Appears the only unique feature is the beamforming... which is supported by 802.11ac and described in Wikipedia:

AE6XE's picture
This product spec defines

This product spec defines beamforming as "RX Eigen Beam Forming".    This means beam forming based on spatial modes of the channel.  This translate to...   exactly what any 802.11n MIMO 2x2 device does when using MCS0 - MCS7 modes.  Two antennas are transmitting the same signal in V-pol and H-pol and the receiver combining the signals using MRC.    

Yea, all 802.11n MIMO capable devices are doing "beamforming" by this definition.    But this is short from what beamforming can be, e.g. changing the signal phases or delayed transmit time and other properties so that the multiple signals transmitted constructively combine at the receiver to archive an overall higher SNR with a given stream of data--to survive in challenging environments--the goal is on higher SNR.  Beamforming trades-off with transmitting multiple streams of data generally what is meant by MIMO or the MCS8 - MCS15 modes (for 2x2 devices)--goal is on higher rates.

Note that Qualcomm advertises "beamforming" as a feature capability in the chipsets AREDN uses.

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