A multiple access wireless communications architecture provides selective, simultaneous communications with wireless devices located in different sections of a spatial area around a communications apparatus referred to as "sectors". This includes communications between wireless devices in a single sector, between wireless devices in different sectors and between wireless devices and a wired network or wireless backhaul network. The wireless communications architecture generally includes two or more wireless antenna arrangements that are each configured to provide communications with wireless devices located in a particular sector. Each wireless antenna arrangement is further configured to determine whether signals are being communicated on a communications channel before transmitting on the communications channel. This may be implemented, for example, using a carrier sense or energy detection mechanism.
