RDP and Wi-Fi: optimization

Question

Computer networks

Hello.
There is a remote desktop server on Win2k8R2 and 8 PCs on Ubuntu 12.04. All users constantly work on RDP (xfreerdp client), use a browser, 1C8 and 7.7, MS Office and TheBat. The computers are connected via Wi-Fi, MikroTik RB951Ui router. Adapters are basically regular TP-link usb whistles. All this is in a small room, separated by a plasterboard partition. Client signal -40...-65 dB, SNR 62..35.
Problem: during active work, sometimes they complain about brakes and breaks, which appear randomly on different machines. At the same time, sometimes the connection speed sags up to 11 Mbps. Any ideas how to make everyone feel good (except for wired connection)?

Answer 1

put a second wifi point?