A communication system supports communication between an end node (101) of a vehicle (103) and a remote correspondent node (105) via a fixed network (107) which comprises a plurality of wireless access points (109) with a directional antenna arrangement for mm wave radio communication using directional beams. A vehicle (103) comprises wireless modems (111, 113, 701, 703) employing electronically steerable beamforming directional antennas for establishing mm wave radio communication links to the access points (109). The air interface communication may use a frequency channels selected from a set of available frequency channels and using a transmission scheme from a set of available transmission schemes. The access points (109) transmit a first beacon data set in a frequency channel using a common transmission scheme and a second beacon data set using a different transmission scheme which is also used for data communication. The first beacon data set comprises an indication of the transmission schemes used for data communication for the access point (109).