The invention provides an antenna array comprising: a plurality of antenna modules, each of the antenna modules comprising an antenna, a signal conductor and one or more microelectromechanical (MEMS) switches, the antenna being conductively connected to the signal conductor, the MEMS switches and at least a portion of the signal conductor being supported by a MEMS substrate; and one or more integrated circuits comprising MEMS control circuitry configured to control the said one or more MEMS switches and/or signal processing circuitry configured to process signals received and/or to be transmitted by the antennas of the antenna modules, wherein the antenna modules and integrated circuits are supported by a common carrier substrate comprising the antennas of the antenna modules, the MEMS switches; or the said one or more integrated circuits. A hierarchy of MEMS controllers includes a master MEMS controller and local MEMS controllers which send control signals to a plurality of MEMS switches.