We just received our first 10 Mbps 5.4 BH (5400BHDD) and I went to set it up and the available carrier frequencies are 5495 -> 5705 !?
How is this a 5.4 BH when it only has one entry at the end of the 5.4 spectrum?
We received 2 of these and they are both the same so it is not some sort of freak thing. I am confused… I would more likely call this a 5.6 BH than a 5.4 when the majority of the spectrum seems to be in the 5.6 range.
5.4 and 5.7 are classified as the same spectrum. And one can interfere with the other. I recommend that you read the Release8user guide and Release notes. There are sections in there regarding the colocation of 5.2, 5.4 and 5.7 BH’s and AP’s.
Frothingdog.ca wrote: 5.4 and 5.7 are classified as the same spectrum. And one can interfere with the other. I recommend that you read the Release8user guide and Release notes. There are sections in there regarding the colocation of 5.2, 5.4 and 5.7 BH's and AP's.
Either you missed the gist of my question or I am missing what you are trying to tell me (and BTW I distinctly asked Moto about this and they said that it was OK to colocate a 5.4 BH with our 5.2 AP's so I hope I am OK there).
I am asking why does a so called 5.4 BH have available frequencies starting with 5495 (the absolute end of the 5.4 range) and going all the way to 5705? Point being that it has only ONE frequency choice in the 5.4 range.
Look at page 141 of the user guide.
OK thanks.
I guess that verifies that the BH are working properly.
Not that it matters, but I am still puzzled as to why they are called 5.4 BH’s? Is there something special about having that ONE 5.4 frequency in there?
BTW. Moto support also thought this was not “normal”. Nice to know they know their products so well… :? I had to get off the phone quickly at the time so we did not pursue this.
And more importantly we will be bridging two sections that have 5.2 BH’s, 5.2 AP’s and 5.7 AP’s. Will the 5.4 BH be able to slide in there w/o interference? Moto told me this was OK.
Steps to a good design:
1. Read the manual on system design
2. Spectrum analysis of RF environment
3. Proximity of RADAR (for DFS)
4. Channel co-ordination
Channel coordination is easy.
Create a spreadsheet in Excel as below. Include any other info such as Lat/Lon, Location, elevation, MAC, Color Code, IP Address, Etc
[FREQ] [NOISE] [RADIO TYPE] [RADIO NAME] [ETC]
5250
5255
5260
.
.
.
.
.
.
.
.
5850
Next you need to fit the radio links in based on 20MHz channels (The recommendation is 25MHz for Advantage AP’s and BH’s). The noise value will tell you how good the link needs to be.
Remember that you can re-use frequencies for AP’s that are face-to-face and back-to-back.
BH Masters need to be on the same tower.
BH/AP on the same tower requires special attention. It’s good practice to place AP’s as close together at one end of the spectrum and the BH’s at the other. The more physical and RF separation you can get between an AP and a BH the better. If you can use a higher gain reflector with a narrow beam and reduce the power on the BH’s you will get better performance. Use only the power you need to establish a reliable link. If -65dB is good, -54 is not better.
An example would be:
Two BH’s are 3 miles apart. The link is stable with the BH’s at max power with no reflectors. Put reflectors on them (+18dB) and reduce the power to low power (-18dB). Same Tx power but the beam goes from 60deg to 6deg.
Don’t use 5.2/5.4 for links providing voice. If the radios detect RADAR and change channels all your voice calls will drop.
Don't use 5.2/5.4 for links providing voice. If the radios detect RADAR and change channels all your voice calls will drop.
You can use SW 8.2.1, there is option when you select region to set two alternate frequencies so the BH can switch automatically. Even there is an option which will reduce false DFS alerts. I can't confirm nothing of this because we just disable DFS.
In HW, if it detects any conflict, it’s a 2 minute outage… 1 min for the AP to determine the alternate channel is clear, and 1 minute for the SM to do the same thing. We have tested this, and in actuality it’s about 1.5 minutes total, but your VoIP is still gonna drop…
I did not test this in SW, as we only do HW.
As much as I HATE to RTFM, with 5.4 it’s a requirement… sadly… 
So yes you can co-locate, but it’s not pretty. You lose 4 or 5 5.2 channels (which is OK), and have the potential to muck with the low end of 5.7…
Brian