Wi-Fi problems with MBP 13'' 2011

I have a 13'' MBP 2011 and when it has been connected for a while to my house Wi-Fi router Internet gets stuck and I have to deactivate the AirPort and activate it again later to make it work. When it gets stuck, if I try any other computer or iDevice the Internet connection works perfectly smooth. Does anyone know how can this be produced? It also seems to happen only with my flat Wi-Fi connection, not with any other I usually get connected to.