A W-band photonic transmitter-mixer, constructed by integrating a planar quasi-yagi radiator for feeding the WR-10 waveguide-based horn antenna and a near-ballistic uni-travelingcarrier photodiode, is used with a mode-locked fiber laser to obtain 2.5-Gb/s impulse-radio (IR) wireless data transmission at around a center frequency of 100 GHz. The bias-modulation technique provides less jitter and a longer maximum transmission distance compared with the technique of modulating the optical pulse train using an electrooptics modulator. Using the bias-modulation technique, we achieve a 2.5-Gb/s IR wireless data transmission.