A method is proposed to realize millimeterwave subcarrier optical signal generation by using a doublewavelength optical spectrum of a certain distance with fiber grating filter. The feasibility is analyzed by designing an apodized moiré fiber grating in which Fourier transformation reverseengineering method is used, the simulation result is also presented, and the related fiber grating filter is fabricated experimentally. Moreover, based on the designed fiber grating and the technology of wavelength division multiplexing, a frequency shift keying radiooverfiber communication system is suggested, and the proposed scheme may be taken as one of the candidates for the next generation highspeed and largecapability radiooverfiber system.