In order to meet ever increasing user bandwidth, future wireless access networks are likely to use high frequency microwave signals as the access media. Hence, radio frequency (RF) signals need to be processed and transmitted with higher bandwidth in many applications. However, the attenuation of RF signals in traditional transmission media increases rapidly when the frequencies of the signal increase. With a high transmission capacity, comparatively low cost and low attenuation, optical fiber provides an ideal solution for accomplishing the interconnections. In addition, a radio system enables the significant mobility, flexibility and easy access. Therefore, the system integration can meet the increasing demands of subscribers for voice, data and multimedia services that require the access network to support high data rates at any time and any place inexpensively. This kind of hybrid radio/fiber system or radio over fiber (RoF) system provides good synergy between optics and radio.