The transmission characteristics of a 120-GHz-band millimeter-wave wireless link are described. The wireless link uses photonic technologies for generation, modulation, and transmission of millimeter-wave signals. This configuration enables set up of the photonic millimeter-wave generator and transmitter core separately; therefore, the wireless link can be used as a kind of radio-over-fiber system. The effects of transmitting 120-GHz-band optical subcarrier signals through single-mode fibers were theoretically and experimentally investigated. It was confirmed that the time shift of the code edges, because of chromatic dispersion, limits the transmission distance. A data stream at 10-Gbit/s was successfully transmitted over the 120-GHz-band millimeter-wave wireless link, with a bit error rate (BER) below 10-12 over a distance of 250 m. The results also demonstrated the stability of the wireless link, which satisfied the 10-Gb Ethernet standard under clear weather conditions.