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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => Wireless and Communications => Topic started by: Jason Lavoie on October 26, 2015, 10:07:49 am

Title: Directional wifi antennas
Post by: Jason Lavoie on October 26, 2015, 10:07:49 am
Has anyone tried directional antennas for wifi control systems?
like this http://www.tp-link.com/en/products/details/cat-5063_TL-ANT2424B.html
or maybe less directional depending on the coverage pattern you need

it seems like most of the time when you need more range you know what direction you'll be heading and could aim the antenna before you head out

Also wondering if I'd need to replace all of the antennas on the router, or just one? (is each antenna for a different band, or is it diversity like a wireless mic?)
diversity doesn't seem likely since a lot of routers have an odd number of antennas so I'm not sure.

Jason
Title: Re: Directional wifi antennas
Post by: Scott Helmke on October 26, 2015, 10:16:32 am
It can be a bit of a crap shoot trying to replace one of those little whip antennas on a consumer wifi box.

That being said, I like this antenna a lot:
http://www.l-com.com/wireless-antenna-24-ghz-8-dbi-circular-polarized-lh-flat-patch-antennas
Title: Re: Directional wifi antennas
Post by: Pete Erskine on October 26, 2015, 11:19:27 am
Has anyone tried directional antennas for wifi control systems?
like this http://www.tp-link.com/en/products/details/cat-5063_TL-ANT2424B.html
or maybe less directional depending on the coverage pattern you need

The Pringles wifi antenna worked well for me and is very directional.  Here is a commercial version:
http://www.cantenna.com/

Quote

Also wondering if I'd need to replace all of the antennas on the router, or just one? (is each antenna for a different band, or is it diversity like a wireless mic?)
diversity doesn't seem likely since a lot of routers have an odd number of antennas so I'm not sure.

Jason

I'd put them on all and separate them by a foot or so
Title: Re: Directional wifi antennas
Post by: Tim Weaver on October 26, 2015, 11:40:52 am
I bought a Ubiquiti Nanostation M5 and can go about a 1/4 mile before I see the signal start to drop. Its a WAP instead of an antenna, but it is directional.
Title: Re: Directional wifi antennas
Post by: Pete Erskine on October 26, 2015, 01:17:04 pm
I bought a Ubiquiti Nanostation M5 and can go about a 1/4 mile before I see the signal start to drop. Its a WAP instead of an antenna, but it is directional.

With the cantenna on both ends it can go a couple of miles.  On 1 end a mile.
Title: Re: Directional wifi antennas
Post by: Jason Lavoie on October 26, 2015, 02:10:56 pm
The Pringles wifi antenna worked well for me and is very directional.  Here is a commercial version:
http://www.cantenna.com/

I'd put them on all and separate them by a foot or so

They're cute, but looks like they're not for sale anymore. the website is there but if you click to buy they are 'closed'
Wonder if they got hit with some regulatory issues

Jason
Title: Re: Directional wifi antennas
Post by: Jason Lavoie on October 26, 2015, 02:13:55 pm
I bought a Ubiquiti Nanostation M5 and can go about a 1/4 mile before I see the signal start to drop. Its a WAP instead of an antenna, but it is directional.

I like it.
and I think the extra complexity of having to add a router (for DHCP) will be outweighed by not having to line up 3 separate directional antennas

Thanks!
Jason
Title: Re: Directional wifi antennas
Post by: Lyle Williams on October 26, 2015, 04:17:30 pm
Every 6dB of antenna gain doubles your range, as long as you are on axis.  Improved reception in one direction is at the expense of reduced reception n other directions.

Antenna gain specs are like speaker specs.  Don't believe everything you read.
Title: Re: Directional wifi antennas
Post by: Pete Erskine on October 26, 2015, 04:28:19 pm
They're cute, but looks like they're not for sale anymore. the website is there but if you click to buy they are 'closed'
Wonder if they got hit with some regulatory issues

Jason

Build it yourself like I did:

http://www.makeuseof.com/tag/how-to-make-a-wifi-antenna-out-of-a-pringles-can-nb/
Title: Re: Directional wifi antennas
Post by: Tim Weaver on October 27, 2015, 09:19:26 am

I like it.
and I think the extra complexity of having to add a router (for DHCP) will be outweighed by not having to line up 3 separate directional antennas

Thanks!
Jason

Yeah I wasn't interested in trying to find a place for crazy antennas on a festival stage. This little guy is about a foot tall and a couple inches deep. I can gaff it to a mic stand on the downstage edge and have plenty of range to reach FOH and well beyond.

I'm using it with a regular linksys/cisco router which also has a 2.4g network in it so my older gear can connect closer to the stage. My FOH clients all are on the 5g network of the ubiquiti.
Title: Re: Directional wifi antennas
Post by: Jason Lavoie on October 27, 2015, 09:25:20 am
Every 6dB of antenna gain doubles your range, as long as you are on axis.  Improved reception in one direction is at the expense of reduced reception n other directions.

Antenna gain specs are like speaker specs.  Don't believe everything you read.

The reason I brought this up is that more often than not my setup is in a corner or at the end of a building and I only care about coverage in one direction.

Often my rack is in the same closet as the network equipment and I can connect to their unused jacks and move my router from place to place in the building, but that gets tedious if I'm going back and forth at all, or I have to bring multiple routers. then remember where I left them all.

Also, I'm thinking I might be able to get away with something like an Airport Express for local coverage in all directions and then add a directional (or two) that I can point at the trouble spot(s).
These ubiquiti units (with mimo elements) seem a whole lot more portable than external directional antennas too.

Jason
Title: Re: Directional wifi antennas
Post by: Jason Lavoie on October 27, 2015, 09:27:40 am
Yeah I wasn't interested in trying to find a place for crazy antennas on a festival stage. This little guy is about a foot tall and a couple inches deep. I can gaff it to a mic stand on the downstage edge and have plenty of range to reach FOH and well beyond.

I'm using it with a regular linksys/cisco router which also has a 2.4g network in it so my older gear can connect closer to the stage. My FOH clients all are on the 5g network of the ubiquiti.

How well does the 5g version go through walls?
I was thinking of sticking to 2.4 since I don't need much throughput and the consensus is that 2.4 should have better range indoors.

Jason
Title: Re: Directional wifi antennas
Post by: Scott Holtzman on October 27, 2015, 12:27:47 pm
A directional antenna is not going to significantly improve penetration.  Frequency is far more important.

Directional antennas provide better interference rejection and improved range on line of site paths. 

If you don't have line of sight you don't have reliability.

Just like one speaker doesn't have better throw than another.  Directional antennas (the yagi and log periodic popular in WiFi applications).  Gain in one lobe (gain is plotted in one dimension as a polar share looking down on the antenna)  is achieved by attenuating it in another.  Omni antenna can get 3 or 4db of gain by squeezing the vertical pattern (like slapping a donut) but then the little ball at the end of the antenna gets very critical.  If accidently removed all the RF will come out the top of the antenna.

The corellary in audio is the HF horn that increases output by concentrating the direction of the sound.



Sent from my SM-N910V using Tapatalk

Title: Re: Directional wifi antennas
Post by: Bob Charest on October 27, 2015, 12:42:40 pm
How well does the 5g version go through walls?
I was thinking of sticking to 2.4 since I don't need much throughput and the consensus is that 2.4 should have better range indoors.

Jason

Hi Jason,

5GHz is more attenuated by walls than 2.4Ghz. The reason why I went with 5Ghz for us is that 2.4GHz is far more crowded between venue Access Points and cell phones. Our Ubiquiti Bullet M5 (5GHz) has been rock solid - we really never have to worry. At a fair when I first brought it in, we tested from over 600 feet away and the connection was great.

I've shut off the 2.4GHz & 5GHz radios in our router and just use the Ubiquiti for an Access Point.

Best regards,
Bob Charest
Title: Re: Directional wifi antennas
Post by: Tim Weaver on October 27, 2015, 01:37:06 pm
I haven't done any real tests of the penetration, but I have seen a few times where the network goes through an outer wall of a club and through the metal skin of our bus and I can get enough signal to control the pa.

This happens when the bus is parked in the coverage area of the antenna and not terribly far away. Maybe under 200'.
Title: Re: Directional wifi antennas
Post by: Jason Glass on October 29, 2015, 08:27:44 pm
I get excellent high gain directional performance on 2.4GHz 802.11 networks when using these: http://www.wa5vjb.com/pcb-pdfs/QuadPatch2400.pdf

You can buy them directly from Kent Electronics or from his son on eBay.  You'll need to add your own coax (a few feet of RG142 or LMR195 is perfect) with a very simple solder joint at the antenna and an appropriate connector (usually an RP-SMA).  I also did a quick spray of Ace Hardware flat black lacquer for a very durable finish.

Jason Glass
Clean Wireless Audio LLC

Sent from my mobile phone.

Title: Re: Directional wifi antennas
Post by: Tim Weaver on October 29, 2015, 10:26:55 pm
I didn't mention earlier, but my 5ghz wap is mounted on a mic stand that also holds one of my ULXD receive antenna. I haven't noticed any problem. I set the mic stand on the downstage edge and point the wap at FOH.