ePMP 1000 delivers LOW throuput

We have critical problem with combination of ePMP 1000 and Cambium 25bdi dish antenna.

Although we did tuning for SM on basis following image (RSSI = -61 dbm) but there are two problem:

1. the most of delay times in DOS ping (left picture) seem good, but almost throuput is very cheap!

2. Although the most of delay times in DOS ping (left picture) and also RSSI (right picture) seem good, we see "Request Time out" message after every 10 to 15 sec.

We were tired for checking all of solution option but it seems that we have to send the radioes to recyclebin! Does anybody know the problem?

Hello rahmandoost,

Could you please attach screenshots of Monitor -> Wireless pages for both AP and SM, screenshots of eDetect search(Tools -> eDetect) for both sides AP and SM.

Issue looks like you have high interference on your channel.

High RSSI does not provides high performance and throughput in case of high interferer floor, firs of all you should evaluate SNR, not RSSI.

Thank you in advance.

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interference is interference no matter what equipment you use weather its Cambium or any other manufacturer. It sounds like interference and that you did not do proper analysis to determine if it would even work to begin with. You cant just throw an AP up and CPE and just expect it to magiclly work perfect.

Doing proper homework first will lead to better results. Sounds like you need to move the AP's to a different area with less noise!

  1. I can't accept that "Noise" is the roblem reason becasue there are other vendors radio modem such as UBNT or Mikrotik that are working good where you think that is noisy location.
  2. If we accept the Nosie as problem root, why SM side deliver good RSSI but AP do it less. Please see the followings images:
  • AP side_eAlign

  • AP_wireless

  • SM_eAlign

  • SM_Wireless

best regards,

M. Rahmandoost

Can you show us, your configuration-radio in AP:

- country :

- ACS : 

- Freq Carrier : (if ACS disabled)

- transmit output power:

- Antena Gain:

- Subcriber Module Target Recieve Level:

- Downlink/Uplink Ratio:

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Hi. Looking at your screen shots, the AP’s radio seems to be outputting at 30 dBm, while the SM’s radio seems to be outputting at 3dBm. That’s 27 dBm mismatch right there, and that might just account for why the SM hears the AP well, but why the AP heas the SM so quietly.

Are you sure that 3dBm is correct? I mean, it’ll be based on your country, your antenna, the local regulatory limits, etc - so maybe that is correct. However, I’ve also seen lots of Typos too where the SM maybe thinks it has a 24dBi antenna when it really only has a 14dBi antenna, and the radio has turned itself down by an extra 10 dB to compensate for the antenna typo.

Also, on the AP side, I assume you have ATPC turned on - if you have that number set incorrectly, that’ll be telling the AP to tell the SM to be quiet. So, we normally set that at -55 or so on the AP. If the ATPC setting on the AP is set to -80 by mistake, then that will tell the AP to tell the SM to turn down it’s transmitter way lower than it should be.

Maybe this has all been covered already in this thread… I’m just saying things that come to mind on why the SM would hear the AP at -58, while the AP only hears the SM at -80. If there is a 22dBm difference, there has to be a reason for it and radio output power setting could be one possible culprit.


I agree look at the SM's tx power first.  Looks wrong to me.

Secondly it's ATPC or ATP, not APC.  You're looking for automatic tx power control (bottom of the radio page, only exists on TDD modes for ePMP).

As I informed in followings Post


The problem root was due to MCS range although I can't present any extra evidence because change of the range affects on link flexibility when attempt in field.

Thanks for all of user cooperation!

Mohammad Rahmandoost

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