Interferences Issue

hi to all
i have a lot of interferences on my cambium network. i have at least 03 relays with ePMP2000 sector, two sectors don’t have smart antena and each of sector have at least 50 SM clients. good signal level with poor wireless link test capacity.
i need ur help guys


Hello, welcome to the community. You can perform a spectrum scan and reconfigure the AP and SM’s to operate in cleaner spectrum. A smart antenna can help because it has a tigher radiation pattern than the sector antenna and will beamform to the SM’s on the Uplink, potentially reducing interference and increasing SNR on UL connections.

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generally, I would just say 50 clients on single sector is WAY TOO MUCH. You can’t get anything out of that sector, really : at 40MHz channel, you would be happy to achieve 400Mbps real throughput in totally clean, interference-free environment. I know it’s very unlikely for all 50 clients to meet at the same time, but it’s not just about that : keeping 50 radios connected to single AP is tedious task.

Synchronization, time allotment etc. Have you ever heard about hidden node problem ?
Have you ever thought : mmmm, how much bandwidth my clients potentially can get ? As I say, brilliant 40MHz channel with 400Mbps throughput only can get something like 8 Mbps per client, not counting with other real-life issues such as different signal strengths, different interferences at each client, hidden node problem, huge retransmissions… That’s too low these days.

Don’t wonder it doesn’t work as expected. It’s a miracle it works at all.
If I would be vendor, I would turn down requests for help in such situation. There’s nothing to be expected. Done.

Lot of interference on top of that. Aye, Sir !


Your best bet might be to add a 3000L AP (if $$ is a factor) with Sector/ Horn and to offload the heaviest users to F300s on the new AP. If you can squeeze the channel space, with proper GPS Sync & channel separation you should be able to do it without self interfering, and it might make a remarkable difference without a lot of$$


I never had good luck with the e2k APs, probably why we dont have any of them any more.
50 SMs on a single e2k AP is too much, check your frame usage and cpu usage and you will find that your over 80% most of the time.
like ninedd, I suggest an upgrade, but mine is go e3k and a RFE dual horn. Plan your number of APs per tower so that you take advantage of frequency reuse. it is important to also set your antenna down tilt so that you do not overshoot your coverage area. On average 10miles (16km) is a very reasonable coverage distance, but do not be afraid to use smaller coverage zones with more APs as signal and SNR are king to speed and reliability. if your using 40mhz channels, then you should see about 200mbps per SM, these radios use a round robin servicing method, so if every SM is wanting to pull max data at once then you would only be able to service about 8mbps per SM and thats IF each SM meets the signal and SNR requirements. Also make sure your using the automatic TX power control and set to -60, this will reduce the desensing your close SMs are doing to your AP and increase the quality of signal to your far SMs higher TX power isnt always best, its about clarity and quality of that signal. frame size is also a factor, the 2.5ms frame is great for lower latency but at the cost of throughput. the 5ms frame size is more universal and used most often by other manufacturers so it is a good trade off for high noise environments. frame ratio is another factor, the power of a GPS syncd network is that it will cut through a lot of noise and reduce your self interference. If all APs transmit at the same time and then listen at the same time, it is unlikely that you will drowned out an SM with an AP that is mere feet away from the other AP. Make sure your frame ratio is the same on all APs. Sector distance is also a factor, all APs should be set to the same distance regardless of the coverage zone, adjust your down tilt to limit the coverage zone so that you minimize your co-channel interference. Whichever settings you use, make sure ALL of your radios are set to the same. If you are using the same band for PTP links consider your data flow requirements and make sure you do not place a PTP AP back to back with a PTP SM, always consider AP/AP and SM/SM. We chose to use 50/50 ratios on all radios regardless of PTP or PTMP as this solved the ratio issues and is consistent against all other noise sources.
DO NOT USE DFS CHANNELS IF YOU CAN AVOID IT. leave DFS channels for home wifi use.

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