An antenna device includes: an antenna array configured to radiate or receive an electromagnetic wave signal; a feed network configured to connect the antenna array and a signal multiplexer; at least one signal multiplexer configured to divide one path of a signal from the feed network into at least two paths of a signal, or combine at least two paths of a signal to one path of a signal and transmit the one path of a signal to the feed network; and at least two interface modules connected to an active module and configured to receive a signal sent from the passive module or the active module, or send a signal to the active module. The antenna device can be used for sharing the antenna array and other parts in the active antenna systems.