Bridge In A Box slow speeds

Greetings!

I've been tasked with the process of setting up the Force 180 PTP bridge for the small company I work for. It connects alright and I've been able to login via the discovery tool and IP, as well as get the devices linked to cnMaestro. Unfortunately I'm getting only uplink speeds of 54 Mbps when doing the Wireless Link Test. Getting 75 down. Advertised as having 200 MBps throughput. The kit consists of two pre-configured ePMP1000 units, which I have not attempted tweaking thus far.

https://www.cambiumnetworks.com/products/backhaul/epmp-bridge-in-a-box/

Tests have been about 50' LOS, and through a double pane window about 300'. Minimal difference through the windows.

Since we are a video studio and I'm not a network or radio engineer, I'm in a little over my head even though I have an IT background.

What information is needed to start improving the speed here? Thanks in advance for any help that can be provided.

Post screen shot of Tools>edect; Monitor>Performance; and Tools>ealign.  Seems you have some interference issues. 

I'm at home now, using cn Maestro. Not sure I've got the right 'Monitor>Performance' and don't see Tools>ealign though I remember seeing that on the IP based UI. I can grab those tomorrow.

FWIW, I'll be setting this up elsewhere, beaming hotel internet to a parking lot for a weekend. Any tips on avoiding interference there will be helpful.

Biggest problem I see from what you have posted so far is an RSSI of -13 for one of the units. This is an extremely strong signal that will overload the front end of the receiver causing severe signal distortion. This is most likely the Slave/SM and not the Master/AP. I have never used the preconfigured units, but I am sure the SM with these kits have auto power set and most likely set to -50 as this is what the other units RSSI displays. 

You will need to log into the Master/AP and reduce its transmit power until the SM shows a RSSI around -50. 

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Definitely don’t let the radios sit any length of time above -35 (closer to zero is louder) it will permanently damage the radio. This is true of nearly all radios.


The epmp do best weaker than 40 usually. If you’ve left them on at this power, turn them off asap

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I've adjusted the AP power from 30 to -20, now getting about RSSI -49 in the SM eDetect.

Upstream speed has improved a little bit. Getting 90.434 Mbps now instead of 53. Down is about the same.

I'll post the requested screenshots again...

SM screenshots:

SM eAlignSM eDetectSM performance 1SM performance 2

AP Screenshots:

AP eAlignAP eDetectAP Performance 1AP Performance 2

AP Link Test results:

Set up indoors, line of sight, maybe 40ft. away.

I'd try to get the signal to -55dBm on each side. ALSO... what channel width are you using? 20MHz or 40MHz? If you're using a 20MHz channel width then 90mbps is pretty close to the theoretical 100mbps maximum HDX. 40MHz should give you about 200mbps HDX maximum, again, assuming perfect conditions.

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That was previously on 20MHz. I went to AP > Tools > ACS, changed to 40, and ran it.

Getting 190.228 Mbps down, and 112.375 Mbps up. IMPROVEMENT!

I'll adjust the signal and try to get more...

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Glad to hear you're getting better speeds! Having a good signal and SnR along with the proper channel width are a few of the keys to success with wireless links!


@Eric Ozrelic wrote:

Glad to hear you're getting better speeds! Having a good signal and SnR along with the proper channel width are a few of the keys to success with wireless links!


Yeah, I'm stoked! The boss will be stoked too! Thanks for the help.

I noticed the SM power was set to auto, value of 7. I changed it to manual and dropped it down to -20. it didn't seem to change the (speed) results of the Wireless Link Test very much. Also tried tweaking the AP power to get RSSI closer to -55 but that negatively impacted speed.

I'm headed outside to do a more realistic setup, through some windows and down the street. Hoping to get similar results as this speed is now usable for our situation.

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This is awesome. Not just for you.. for all of us..I love seeing the community coming together to help each other. 


@CWB wrote:

This is awesome. Not just for you.. for all of us..
I love seeing the community coming together to help each other. 



Yeah, I was just thinking how awesome and knowledgable this community is, especially members like @Eric Ozrelic.  With Cambium probably in WISPAPALOOZA limbo this week, its great to have a community like this.

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Thanks again for all the help on this. After going outside, through windows, when first setup it was barely connecting. I could see the web gui, then shortly after it would indicate disconnection and begin scanning again. I did need to bump up the TX strength on the AP to keep RSSI values in the mid-50s, and then was able to maintain a steady connection with good speed.

Hoping all goes well when set up on the Vegas strip with tons of radio signal bouncing around! Looks like AP does an auto channel selection at boot if that option is selected.