There are frequent disconnection in associations because of multipath scattering or multipath distortion
Generally as the RF signal starts travelling away from the transmitter they grow wider. When this expanding signal encounters an obstacle on its way , it is reflected , refracted etc. This reflection creates multiple wave fronts which takes mulitple path towards the receiver. This feature is called multipath. These waves experiences more delay than the main signal.
Genrally signal quality is reduced because of multipath behaviour. When the reflected signal arrive out of phase it adds to the signal strength of main signal. When they arrive in phase it adds to the signal strength of the main signal.
One way to reduce the effect of multipath scattering is to use diversity(Dual) antennas. Idea behind diversity is : beacause antennas are physically sepearated, even if signals received on one antenna is worst, there is a probability that other antenna is reinforced by the inphase reflected signals . Most access points nowadays come with Dual antennas. Even if deployed manually , make sure antennas are only 5 inches apart.
Remove the obstacles if possible thereby reducing the possiblity of Mulitpath. Generally Wireless Lans deployed in open environments which are free of obstacles they are not affected by Multipath.