Radio over fiber (ROF) systems which employ intensity modulation with direct modulator are faced with severe chromatic dispersion-induced fading of the remotely delivered RF signals, which limits the development of millimeter-wave communications technology. Optical frequency multiplication (OFM) carry low frequency or intermediate frequency modulated signals on optical signals. The base station generates millimeter-wave signals, which effectively combatted the problem of chromatic dispersion-induced fading. This method has broad development prospects. The design of a bi-directional radio over fiber transmission system based on OFM is proposed and experimental studied. In the system, a fiber Bragg grating is used to extract light wave as a light-uplink carrier. The base station needing no light source. The loss of optical power is low, the use of resources is rational. At the base stations, low-frequency oscillator and millimeter-wave carrier are mixed to gain the uplink oscillator, which solve the problem of uplink generation. This method simplifies the system and lowers the cost.