The invention relates to antenna apparatus comprising: an antenna, a signal conductor and one or more RF 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 crystalline MEMS substrate; and a capping substrate comprising a capping portion, wherein an enclosed volume is formed around the said MEMS switches between the capping portion and at least a portion of the crystalline MEMS substrate, and wherein the capping substrate comprises the said antenna.