Keith C. Perry on 25 Apr 2016 13:03:35 -0700


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Re: [PLUG] Live streaming sports events (Cross posted to Tech list at LOPSA)


Well, you not and idiot John  :D

Ok, so 600 yards...

I had to reacquaint myself with some of that math but here's my thinking...

Signal intensity is inversely related to its distance from a source by factor of two.  That is to say

I = 1 / d^2

d = distance in meters

Signal strength comparisons are most commonly done in dB so

dB = 10 log (I / I0)

I = the intensity at the target distance, 600 meter (you could say yards since that's not that different, ~9% difference)
I0 = the intensity of a typical wifi user.  So lets set that to 50 meters.

I come out with -21.58 dB of signal loss (attenuation).  At 600 meters you'd want to have at least 21.58 dB of antenna gain to give those users the same experience as someone at 50 meters.

That just the basic math which assumes free space loss- there is no accounting for lose though material of other densities such as the trees mentioned or multi-path / scattering issue that the metal bleachers would cause.

So 24dB gain is probably the minimum place to start for the backlink...

http://www.neweggbusiness.com/Product/Product.aspx?Item=9B-33-997-212&nm_mc=KNC-GoogleBiz-PC&cm_mmc=KNC-GoogleBiz-PC-_-pla-_-Network+-+Network+Antennas-_-9B-33-997-212&gclid=CjwKEAjwgPe4BRCB66GG8PO69QkSJAC4EhHhHrHHj-Irq72C-gM4bix1DrPcfFw7mY1vlWCmdYpUxBoCO-jw_wcB

...and then you'll still use the omni antenna on the field.

I'll admit that this is pretty far but I've heard of people running some pretty long distances... like over a mile... with high gain directional antennas.  You'll see a lots of stuff out on about the coffee can (cantennae) direction antennae so I would say that the only way to tell for sure is to try it out.  The math doesn't always predict an absolute result, especially with such a raw estimate.  This doesn't even take into account what kind of live stream could be supported.  What works for web browsing may not work for an a/v stream.  An SD stream might work but HD might not, etc...

I'd be willing to help you try out some scenarios if want to give it a go.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
Keith C. Perry, MS E.E.
Owner, DAO Technologies LLC
(O) +1.215.525.4165 x2033
(M) +1.215.432.5167
www.daotechnologies.com


From: "john boris" <jborissr@gmail.com>
To: "Philadelphia Linux User's Group Discussion List" <plug@lists.phillylinux.org>
Sent: Monday, April 25, 2016 2:12:39 PM
Subject: Re: [PLUG] Live streaming sports events (Cross posted to Tech list        at LOPSA)

Keith,
Thanks. The press box is close to 600 yds from the main building with a clump of trees which might infringe line of site. There is no Sprint 4g near there and the verizon 4G gets two bars there. With all of the aluminum (Bleachers and Press box) the wifi signal gets attenuated. I had a Linksys (Cisco) E4200 router there and had a hard time to connect to the sideline ipads to handle quick shot shares. I am not sure if a lot of that was ID10T errors or the attenuation issue. 

On Mon, Apr 25, 2016 at 1:53 PM, Keith C. Perry <kperry@daotechnologies.com> wrote:
As Eric was alluding too, if you have a wifi source within line of site you should be able to get decent signal by putting up some high gain directional antennae.

Ubiquity has products for this (airMax) but would be for a substantial build out but a combination of these:

http://www.amazon.com/Brands-Wireless-2-4GHz-Antenna-Booster/dp/B0054MLMLA

and


You'll probably need might need some additional gender changers or connector adapters (e.g. N-female to male or female SMA) but its a simple enough project as long as the distance isn't too great.

The idea would be to have the direction high gain antennae create the link back to the main building and then you have the omni directional unit provide the on field servicing.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
Keith C. Perry, MS E.E.


From: "john boris" <jborissr@gmail.com>
To: "Philadelphia Linux User's Group Discussion List" <plug@lists.phillylinux.org>
Sent: Monday, April 25, 2016 10:04:14 AM
Subject: Re: [PLUG] Live streaming sports events (Cross posted to Tech list        at LOPSA)

Eric
Thanks for the reply. A few years back when I was at another school I looked into it but at that time the cost was prohibitive. But prices have plummeted and it might be an option now.

On Monday, April 25, 2016, Eric H. Johnson <ejohnson@camalytics.com> wrote:
John,

I have never done anything like you are talking about, but a point to point wireless bridge may do what you need. A company I worked with years ago used the same basic technique to link two of their buildings together, so as to avoid getting two, at the time, expensive T lines. Of course the technology has changed a lot since. Anyway, here is an inexpensive one on Amazon:
http://amzn.com/B00OJZPNG8

I presume you would need two of them, one connected to the schools network, and the other at the field. It can be powered with the Ethernet port, thus powered by whatever setup is being used to record the event. I do not know how difficult they are to align. For home games,  it can be set up permanently just one time. Road games may be a different matter, if you want to do that as well.

Then use your favorite live streaming service. See here for a review:
http://www.streamingmedia.com/Articles/Editorial/Featured-Articles/A-Buyers-Guide-to-Live-Streaming-Services-95465.aspx

Regards,
Eric




Where I coach Football they have decided to look into live streaming our games this upcoming season and since I am the teams "Computer Guy" they have asked me to look into this. I am searching the web but I would really like to talk to someone who has done this. We don't have a dedicated Internet connection at the field so we would have to use Celluar. I have searched for hot spots near the field but as usual Sports fields usually end up in dead zones.

So if anyone on the list has experience with this even using a service I'd appreciate it if I could converse with you.

TIA


--
John J. Boris, Sr.
Resident Computer Geek and Football Coach.

___________________________________________________________________________
Philadelphia Linux Users Group         --        http://www.phillylinux.org
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--
John J. Boris, Sr.


___________________________________________________________________________
Philadelphia Linux Users Group         --        http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion  --   http://lists.phillylinux.org/mailman/listinfo/plug

___________________________________________________________________________
Philadelphia Linux Users Group         --        http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion  --   http://lists.phillylinux.org/mailman/listinfo/plug




--
John J. Boris, Sr.

___________________________________________________________________________
Philadelphia Linux Users Group         --        http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion  --   http://lists.phillylinux.org/mailman/listinfo/plug
___________________________________________________________________________
Philadelphia Linux Users Group         --        http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion  --   http://lists.phillylinux.org/mailman/listinfo/plug