If you are not using Bluetooth*, please disable it as it uses the same antennas and this may impact your Wi-Fi speeds. Because Bluetooth* and Wi-Fi transmit in different ways using different protocols, interference can occur when Wi-Fi operates in the 2.4GHz band. Bluetooth wireless technology and 802.11b/g both use the 2.4 GHz ISM (Industrial, Scientific, Medical) unlicensed spectrum, and in some configurations can interfere with each other.
Also Find the optimized wireless connection settings between the WLAN adapter and the router. By choosing the settings which suits the network environment and the router, you can have a better connection quality and more stable connection. Let us know if this information helped you.
It is important that you know that this wireless card has 3 antennas and in order for you to get the same throughput your router also needs to have 3 antennas.
Updating the firmware on the router and the drivers for the wireless card can help as well. Please check the links below as they may help you answering your question.
Let us know if these pieces of information helped you.