An impulse-radio ultrawideband (UWB) photonic generation technique based on frequency shifting in the remote connectivity fiber in optical access networks is proposed and analyzed in this paper. This technique is based on optical carrier suppression modulation combined with fiber chromatic dispersion targeting to overcome the bandwidth limitation of optical upconversion, with the advantage of being easily reconfigurable generating simultaneously different RF bands. A comprehensive simulation analysis is performed with special focus on capabilities for dual 24 GHz/60 GHz operation paired with experimental demonstration at 1.24 Gb/s. 60 GHz wireless performance after optical generation and transmission in 12.5 km of standard single-mode fiber is measured demonstrating error-free transmission at 1 m radio distance. The inclusion of remote Gaussian-monocycle pulse shaping is also analyzed in this paper considering dual 24 GHz/60 GHz operation. Pulse-shaped dual 24 GHz/60 GHz generation is experimentally demonstrated at 1.24 Gb/s. Transmission performance is measured at 24 GHz demonstrating error-free transmission. The simulation analysis further indicates that the technique is suitable for UWB generation at higher RF bands such as the W-band (75-110 GHz). Practical implementation considerations and trade-offs (e.g., in terms of cost and number of remote antenna units supported) of this system are also analyzed by simulation showing that the technique is cost effective.