Abstract: A wireless communication system comprises wireless access points arranged to communicate with wireless communication units using mm wave radio communication links formed in communication sub-channels that are given by a bandwidth, a channel frequency, a large frequency offset, and a small frequency offset. The access points transmit beacons and the communication units seek to discover access points by scanning. A scanner of the communication unit scans communication sub-channels for a beacon transmitted by a wireless access point and terminates the scan if a beacon is detected. The scan order is arranged to keep the small frequency offset fixed while varying the large frequency offset. A controller controls a communication circuit to set up a mm wave radio communication link to the access point of a detected beacon. This may allow faster scanning with typically an improved and faster detection of a beacon from a suitable access point.