A wireless local area communications network that includes one or more access points each of which may have associated wireless communications devices in communication with it over a plurality of channels, some of which may be shared with a radar signal. The wireless communications devices are able to roam from one access point to another access point, in the presence of the channels shared with radar, in a seamless manner or in a manner in which the current communications session is not interrupted or delayed due to the requirement that any device in the network not transmit on those channels being shared with radar signals until the device can confirm that the channel is radar free. Furthermore, it is possible to guarantee that the communications session will not be disrupted during such roaming by configuring the wireless communications device to scan the wireless medium for only a minimum period of time necessary to detect a regularly occurring signal.