Disclosed are exemplary embodiments of V2X antenna systems. In an exemplary embodiment, a V2X antenna system comprises a coupler and a microcontroller. The coupler is operable for sensing radio frequency (RF) power and relaying the information to the microcontroller. The microcontroller is operable for controlling RF switches to selectively activate either a transmit path (Tx-path) or a receive path (Rx-path) based on the information from the coupler. The microcontroller may also be operable for controlling one or more attenuators to control attenuation of signals.