Asysmetric speed and disconnects at high load

Hello,

on a very short link (300 m) I have an asysmetric speed and disconnects at high load. I have tried a lot, but so far no success. I would appreciate any help and suggestion.

Here is the configuration:

Site 1 - RB450G – RB411 (Antenna1) - WLAN Link - (Antenna2) RB411 – RB450G - Site 2

The WLAN LINK is a 100 MBit/s link and internal the bandwith test between the antennas is fine.


All components are running with Router OS 5.7
Both RB450G and RB411 are configured in the same way


This shows the transfer of o big file in both directions. As you could see, in one direction the speed is a little bit less and the number of packets/s is fluctuating

When I try to transfer the file in both directions at the same time, then in most cases the connection is lost.

Log entry on one of the RB411: disconnected, control frame timeout.

Sometimes it works, but then I see the following picture:

Sometimes the speed is going down dramatically. Here an example:

What is causing this trouble ? Any ideas ?

regards