Spectral efficiency and energy efficiency balanced full-duplex recognition relay communication method

The invention discloses a spectral efficiency and energy efficiency balanced full-duplex recognition relay communication method. The method comprises that an emitter and receiver pair of an authorized user, an emitter and receiver pair of an unauthorized user and a full duplex relay unit are included; and the full duplex relay unit includes three relay communication modes, namely the mode of only assisting the authorized user, the mode only assisting the unauthorized user and the mode of assisting both the authorized user and the unauthorized user simultaneously, the optimal values of the energy efficiency are compared under the constraints of the spectral efficiency, and the relay communication mode corresponding to the optimal energy efficiency value is maximal is selected. The optimal relay communication mode is selected according to the optimal value of the energy efficiency, the spectral efficiency and the energy efficiency of the system are balanced, and the method is suitable for the frequency band sha