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Which Band?

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Which Band?

I am looking to deploy some of these on top of a hill,

The 2.4 band has 1, 10MHz channel,
5.8 band has 4, 10MHz channels,
And 3.4 has 12, 10MHz (6, 20MHz) channels, that's an awful lot, is this true?

Yet actual use is the opposite of channel availability according to the map,
As far as cost its 5.8, 2.4 then 3.4 band.

Why so little interest in the 3.4GHz band?


A lot of this will depend on
A lot of this will depend on area design.

2.4GHz has a following partially from the old days of being the first band to be supported (before we even had channel -2) in that regard it makes it the most compatible band to buy equipment for and it self reinforces the trend. 

Where I am at 3.4 GHz is reserved exclusively for coordinated PtP Backbone links. This is because it is a clean band with limited interference and backbone connections are the most critical links they need to be coordinated and protected. Equipment costs are also higher for this band which tends to put most Amateur Radio operators off as they prefer to save as much as they can. 

Around here 5.8 GHz is used from Bacbone to "mid mile" nodes which then redistribute 2.4GHz for local access. 

Users come in on 2.4 - Local relay points talk to hilltops on 5.8 GHz  and Mountains talk to each other on 3.4GHz 
You end up with no contention on the feeder sites since its always cross band. 

2.4GHz is a little less sensitive to obstructions while 5.8 can be very sensitive which means 2.4GHz can work in some less than ideal spots while 5.8GHz will be more likely to have issues.  Conversely though this also means there is more noise in band because 2.4GHz travels further than 5.8GHz since it pssses through walls a bit easier.
AE6XE's picture
KI6GVW,  reference this post:
KI6GVW,  reference this post: .   5.8 band has ~9 x 10Mhz channels with clear sailing.    Also,  there are a lot more 3Ghz and 5Ghz devices in use than the map seems to show.   One can download a kml file to load into google earth and get a better perspective of the deployed devices.   There are many non-2Ghz devices not showing in the layers unless you zoom in to see them location by location. 

Which Band

The Ubiquiti NanoBridge M5 can run on the channels 177 to 184?
I was thinking to use the NanoBridge M5 25

Radio Model Ubiquiti NanoBridge M5 25
Antenna Beam-Width
BER 0% 1E-6
Modulation / SNR 32PSK /
Receiver Antenna +12dBi

These would be some of the AP's

location simulated coverage
AE6XE's picture
Yes, the AREDN firmware
Yes, the AREDN firmware supports up to ch 184 on all the listed 5Ghz devices.  

The IND-298 coverage would connect you into the SoCal mesh network reaching all the way to Riverside, Temecula. San Bernardino, Orange County and beyond.  Check out the attached pic of a live snapshot from a Rocket with 120deg Sector coverage located at JPL.  Note K1BAA-NBM5-60-231-172 is a neighbor.  K1BAA QTH is a stone throw away from IND-298 location and is showing a ~39 TxMbps link in both directions with JPL right now.  This is a live link using an NBM5 5G25, demonstrating  almost identical to your coverage map.  You may want to connect up with each other locally.

There is also a 3Ghz P2P link going right over the top of you between JPL and Peasants PK.  You would be able to connect in ether direction to these higher gain devices and could achieve over 50Mbps links.  Lots of options.

Did we meet at Scale 15x, I was in the AREDN booth at the Pasadena convention center?   We were talking about this location?   Let's connect up separately and explore the local options to fill out coverage <callsign> at .

Image Attachments: 
to the web page
How do you get to the web page that is in the attached image?
Yes we meet at Scale and this

Yes we meet at Scale and this is that site. I have another close by too, this will give an idea what it can do.

The Industry site is right on the JPL and Pleasants Pk path, would not even need to re-align.

The link
Image Attachments: 

This is a close simulation of the coverage,

The Pleasants Pk OC coverage from the 240° facing 19 dBi antenna which is calculated with very similar parameters for comparison,

still working on the design

A spreedsheet

A spreedsheet. It still needs work. The frequencies will change as no consideration yet on colocation or AREDN stuff.
The simulated coverage is based on 16PSK/18 and a BER of 1E-6. MCS10 more or less.
this would much benefit by being high up on the tower, so may be delayed

Support File Attachments: 
K5DLQ's picture
by the way, that does not
by the way, that does not appear to be a valid support file that you attached.  Support files are downloaded from the link at the bottom of the Setup/Administration page on the node (Download Support Data).
Where is that?
Where is that?
WU2S's picture
Location of Support Data tool

It is at the bottom of the Administration page
Or you can access it using the following URL: http://localnode:8080/cgi-bin/supporttool 

Support Data link location

Is the NSM3 is what is used

Is the NSM3 is what is used on both ends of the JPL/Pleasant Pk backhaul? The next question is how easy is it to physically get to each end?

AE6XE's picture
At present, the Pleasants Pk
At present, the Pleasants Pk to JPL link is using NSM3s with the following reflectors attached.  The gain is claimed by the vendor to be better than the NanoBridge M3, however the reflector by itself has no gain specifications.   From a modeling perspective the NanoBridge M3 is the best known substitute.

There is discussion of replacing these with a Rocket M3 and a RocketDish.   Also, discussions are taking place to extend a backbone link through Verdugo Pk.  The Ventura group will have extended down to this peak in June/July 2017.    Also, note that the W6TRW group is planning to be on the mesh in time for Field Day at Friendship Park at Palos Verdes.   With future possibilities on the TRW ~8 story facility in Redondo Beach, there are beginning to be multiple prominent options in LA County to further coordinate.    

Do you know the average RSSI 
Do you know the average RSSI  on one or both of the JPL/Peasants links?
AE6XE's picture
last 48hr SNR

Live screen shots for last 48hr SNR on this 40+ mile link flying over LA area. We generally see ~25TxMbps both directions.

Image Attachments: 
This is the link to the

This is the link to the spreadsheet,

I am in-between Verdugo and Pleasents Pk too.

Support File Attachments: 
If I got in between Pleasents to JPL

If I got in between the Pleasents to JPL the throughput would go up to maybe 40MBs over 25MBs, a 15MBs improvement. More bandwidth would aid in increasing speed.

5.8GHz options offer wider bandwidths,
Supported AREDN options for the backhaul,
Rocket 34 for about 500$
PowerBeam M5-400-ISO for about 100$

Does AREDN support 40MHz or 80MHz channels?
Is there any reason not to use an AirFiber rig for a backhaul? Bridge it, lock the MACs no encryption and call it done.


Using the website search this
Using the website search this is the first result

40mhz support discussed here:
AE6XE's picture
Part 15 channels aren't an
Part 15 channels aren't an option at PP.  There are 3 WISPs and these channels are fully consumed.   I believe the AirFiber does encryption in hardware with no options in AirOS to turn it off. It isn't compatible to do part 97 channels that I'm aware of.   (If anyone would like to donate one to the AREDN team., we'd be happy to further investigate :) . ) 

The 40Mhz and 80Mhz bandwith options are technically possible to add support for in AREDN.  I've tested 40Mhz channels previously.   However,  the xmit power is fixed and as we increase the channel width, we are stretching the same power across that larger bandwidth.  This means for the individual OFDM carrier waves, the 'bins' as they are called, the SNR is going down, hence less throughput per bin.   We're not using 20Mhz today as we're finding the larger bandwidth is not enabling higher thoughput for these long distance links, consequently 40Mhz and 80Mhz options wouldn't add any value.   But this is in higher noise Metro areas.  Those with low noise environments may benefit.    The bigger channels and 802.11ac, with even larger channel widths, are best used at shorter distances where the SNR is still good to achieve such high rates.    

Let's connect up separately at a local level to further discuss the specifics.   


We have to meet up,
Those feedhorns (less the dish) look interesting,
We are working on a way to add 39 dB into your backhaul path, if we were successful that might make 40MHz work,

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