A tunable antenna. includes a radio frequency integrated circuit, a first frequency modulation branch coupled to the radio frequency integrated circuit, a first antenna coupled to the radio frequency integrated circuit through the first frequency modulation branch, a second antenna coupled to the radio frequency integrated circuit through a second frequency modulation branch. The first antenna corresponds to a first frequency, the second antenna corresponds to a second frequency, and the first frequency and the second frequency are respectively a transmit frequency and a receive frequency in a specified frequency band. The first antenna and the second antenna are respectively connected to the radio frequency integrated circuit through the frequency modulation branches when the tunable antenna is being designed.