Embodiments of the present application disclose an antenna device and system. The 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 signal from the feed network into at least two paths of signal, or combine at least two paths of signal to one path of signal and transmit the one path of signal to the feed network; and at least two interface modules connected to a passive module or an active module, is configured to receive a signal sent from the passive module or the active module, or send a signal to the passive module or the active module. The present application can be used for sharing the antenna array and other parts in the active and passive antenna systems.